PSYCHOLOGY: Chapter 6 - The Body and Behavior Lecture Notes

* Bold print denotes an item not in the text.

 

 

 

 

 

 

6-1: The Nervous System: The Basic Structure

 

Runner's high: the natural “second wind” an athlete gets when endorphins are secreted and produce euphoria.

 

Endorphin: neurotransmitter that inhibits pain.

 

2 points on the nervous system:

        1.) The nervous system is never at rest. There is always a job for it to do.

        2.) Even when you are sleeping the nervous system is busy regulating your body functions.

 

4 things the nervous system controls:

        1.) emotions

        2.) movements

        3.) thinking

        4.) behavior

 

2 parts of the nervous system:

        1.) Central nervous system (CNS): Brain and spinal cord

        2.) Peripheral nervous system (PNS): the nerves branching out from the spinal cord

 

 

3 points on the PNS:

        1.) The nerves of the peripheral system conduct information from the bodily organs to the central nervous system and take information back to the organs.

        2.) These nerves branch out from the spinal column.

        3.) In size they are about as thick as a pencil (spinal nerves) to invisibly small (in the extremities).

 

Nerve fibers: These are what we call "nerves".  These carry chemical-electrical messages from receptor cells to brain in 1/50 of a second.

 

     * A-alpha nerve fibers: carry information related to proprioception (muscle sense).

     * A-beta nerve fibers: carry information related to touch.

     * A-delta nerve fibers: carry information related to pain and temperature.

     * C-nerve fibers: carry information related to pain, temperature and itch.

 

Central nervous system:  Powerhouse of the body made up of the brain and spinal cord.

 

Protection of the Nervous Systems:

        4 types of protection:

                1.) sheathing

                2.) meninges

                3.) vertebrae

                4.) skull

 

Sheathing (myelin): A white, fatty substance that insulates and protects the axon for some neurons, and protects the brain and peripheral nerves.

 

Meninges: Series of 3 membranes that cover the brain and spinal cord.

    

           - Dura mater, The outer layer of the meninges is called the dura mater or just the dura. The dura is a tough and thick fibrous

                            material.

    

           - Arachnoid: The middle layer is called the arachnoid -  A clear membrane with fine strands (resembles a spider's) that surrounds a cap

                          of cerebrospinal fluid that covers the surface of the entire central nervous system.  Below the arachnoid lies the

                          subarachnoid space.  The cerebral arteries run through the subarachnoid space.  (The subarachnoid space is the space into

                          which aneurysms of the cerebral vessels hemorrhage.)

 

           - Pia mater: The innermost of the three membranes (meninges) that surround the brain and spinal cord of vertebrates is called the pia

                          mater (or just the pia). The pia mater lies immediately adjacent to the central nervous system, and the choroids plexus,

                          which secretes cerebrospinal fluid, is an extension of it.

    

It's all kind of like the brain wrapped in Saran wrap, put in a sandwich bag, and then sealed in a Ziploc bag.

 

Vertebrae: The adult vertebral (spinal) column consists of 26 bones that are grouped as follows:  (** See diagram in study guide)

 

     - cervical vertebrae: #7 in the neck; numbered C-1 to C-7. C-1 and C-2 do not move.   

 

     - thoracic vertebrae: #12 that articulate with the 12 pairs of ribs; numbered T-1 to T-12.  Some rotation can  

                             occur between the thoracic vertebrae, but their connection with the rib cage prevents much

                             flexion.

 

     - lumbar vertebrae: #5 of the lower back; numbered L-1 to L-5).  These vertebrae are very robust in construction,

                           as they must support more weight than other vertebrae. They allow significant flexion and extension.

 

     - sacrum: #1 which is actually a fusion of 5 sacral vertebrae.  Fusion occurs from late teens to early 20's.

 

     - coccyx or "tailbone": #1 which is a fusion of 4 coccygeal vertebrae

 

 

Intervertebral discs: located between adjacent vertebrae. These fibrocartilage discs form strong joints and absorb spinal compression shock. 

                       Each disc allows slight movement of the vertebrae, and acts as a ligament to hold the vertebrae together.

 

 

        * Disc degeneration: Over time, spinal discs dehydrate and  become stiffer, causing the disc to be less able to adjust to compression.

                       While this is a natural aging process, in some individuals, as the disc degenerates it can become painful. 

 

     * Disc problems: Because of the way it is attached to the vertebra above and below it, a disc cannot “slip” as commonly thought. However,

                          trauma and injury to the spine can cause discs to bulge, be herniated or, even worse, rupture. This can be quite painful,

                          putting pressure on the spinal cord and nerve roots, interfering with function - and causing pain.

    

           ^ 3 common types:

               

                1.) Disc Tear: The most common disc injury is a small crack or microtear in the tough, outer cartilage material of the disc

                                   (called annular fibers). This allows the fluid to start leaking out, and the disc begins to wear thin.

 

                2.) Bulging Disc: The soft jelly-like material in the middle of the disc pushes to one side, forward, or backward, and swelling

                                     occurs. The nucleus is still contained within the tough outer fibers of the disc, but can still cause pressure and painful symptoms.

 

                3.) Herniated Disc: The soft jelly-like material from the nucleus in the middle of the disc ruptures through the tough, outer fibers and extends to the outer edge or beyond

                                         the normal limits of the disc.

 

Spinal cord: is about 45 cm (18 inches) long in men and 43 cm long in women. However, this is much shorter than the length of the bony spinal column. In fact, the spinal cord extends down to

                only the last of the thoracic vertebrae. Therefore, nerves that branch from the spinal cord from the lumbar and sacral levels must run in the vertebral canal for some distance

                before they exit the vertebral column.

 

           * spinal nerves: 31 pairs of nerves that extend from the spinal cord outward to the body.

 

           * cranial nerves: are 12 pairs of nerves that can be seen on the ventral (bottom) surface of the brain. Some of these nerves bring information from the sense organs to the brain;

                                 other cranial nerves control muscles; other cranial nerves are connected to glands or internal organs.

 

Brain:

           * contains three-fourths of the body's neurons about (100 billion neurons).

           * weighs about 3 pounds (human head weighs 8-10)   About 2%-3% of the human body weight.

 

Skull: There are 8 bones that surround your brain. These 8 bones make up the cranium. Another 14 bones in the face make up the entire skull. There is a large opening, called the

        foramen magnum, located in the back of the occipital bone. This is where the medulla ends and projects out of the skull. Smaller holes in the skull, called foramina, allow nerves and

        blood vessels to enter and leave the cranium.

 

       - sutures: the places in the skull where the bones come together fused together. These sutures are flexible in young children, but become fixed as you age.

 

Paralysis: the loss of power of voluntary movement in a muscle through injury or through disease, or the loss of sensation over a region of the body, of its nerve supply.  Paralyzed means one cannot move due to

                a severed spinal cord.

 

Spinal Cord Injury Packet

 

Neurons: the long, thin cells that constitute the structural and functional unit of nerve tissue along which messages travel to and from the brain.

 

        Brief points:

                - the oldest and longest cells in the body. You have the same neurons for your whole life.

                - the human brain has about 100 billion neurons.

                - have specialized extensions called dendrites and axons.   

                - can flash, (burn) hundreds of times a minute, and normally don't burn out.

                - new research says that these may regenerate in certain situations.

 

                - how messages are transmitted:  Chemical electrical signals travel down the neurons much as flame travels along a firecracker fuse.   Transmission between neurons occurs whenever the cells

                                                                    are stimulated past a minimum point and emit a signal.

 

        - # of times a neuron can “burn”:  the neuron can fire (burn) over and over again, hundreds of times a minute.

 

        - "all-or-none" principle:  when a neuron fires, it does so at full strength. If a neuron is not stimulated past the minimum, or threshold, level, it does not fire at all.

 

                * comparative example: In an engine, the sparkplug ignites the gaseous vapor in an engine cylinder.  The piston (within the engine) does nothing until the sparkplug fires, causing the

                                          vapor to explode.

 

        - 3 basic parts: the cell body, dendrites, and axons.

 

                * cell body: contains the nucleus and produces the energy needed to fuel neuron activity.

 

                * dendrites: (receiver) are short, thin fibers that stick out from the cell body, that receive impulses, or  messages, from other neurons and send them to the cell body.

 

                * axons: (sender) is a long fiber that carries the impulses away from the cell body toward the dendrites of the next neuron.

 

                                ^ size: can be very short or several feet in length.

 

Differences between axons and dendrites

 

Axons                                                          Dendrites

Take information away from the cell body                   Bring information to the cell body

 

Smooth Surface                                                       Rough Surface (dendritic spines)

 

Generally only 1 axon per cell                                Usually many dendrites per cell

 

No ribosomes                                                          Have ribosomes

 

Can have myelin                                               No myelin insulation

 

Branch further from the cell body                           Branch near the cell body

                                     

Neurons can be quite large - in some cases, like corticospinal neurons (from motor cortex to spinal cord) or primary afferent neurons (such as those extending from the skin into the spinal cord and up to the brainstem) can be several feet long!

 

        - myelin sheath: A white, fatty substance that surrounds some neurons (neural tissue).

 

                * 3 duties:  Insulates and protects the axon, and speeds the transmission of impulses.

 

                * Multiple Sclerosis:  nervous system disease in which the myelin sheath is destroyed, and as a result, the behavior of the person is erratic and uncoordinated.

 

        - axon terminals: branch out at the end of the axon;  terminals are positioned opposite the dendrite of another neuron to receive impulses.

 

        - Synapse: the gap that exists between individual nerve cells.  It is a junction or connection between the neurons where the neuron transmits its impulses or message to another neuron.

 

                * size:  less that one millionth of an inch wide.

 

                * contents:  filled with fluid that transmits the chemicals from one neuron to another.

 

        - Neurotransmitters: the chemicals released by neurons, which determine the rate at which other neurons fire.  Neurotransmitters open chemical locks or excite the receptors.

 

                * excite: making a neuron transmit.

 

                * inhibition: stop a neuron from transmitting

 

                * flow: in only one direction.

 

                * examples:

                        ^ Norepinephrine: A substance, both a hormone and neurotransmitter, secreted by the adrenal medulla and the nerve endings of the sympathetic nervous system to cause blood vessel constriction

                                                    and increases in heart rate, blood pressure, and the sugar level of the blood.  This neurotransmitter is also involved with  memory and learning.

 

                        ^ Endorphin: neurotransmitter that inhibits pain. (and

                                           kind of creates a euphoria.

 

                * supply level differences:  The oversupply or undersupply of

                                                          certain neurotransmitters has

                                                          been linked to certain diseases.

 

                        ^ Acetylcholine:  a neurotransmitter involved in

                                                  movement and memory.  A decrease

                                                  in this neurotransmitter is

                                                  associated with paralysis and

                                                  Alzheimer’s disease.

 

                                + Alzheimer's disease:  currently an irreversible,

                                                incurable condition that destroys a

                                                person’s ability to think, remember,

                                                relate to others, and care for her or

                                                himself.

 

                        ^ Dopamine:  neurotransmitter involved in learning,

                                           emotional arousal, and movement.  An

                                           oversupply of this neurotransmitter is

                                           associated with schizophrenia, and an

                                           undersupply associated with Parkinson's

                                            disease.

 

                                + Schizophrenia:  a group of severe psychotic

                                                         disorders characterized by

                                                         confused and disconnected

                                                         thoughts, emotions, behavior,

                                                         and perceptions.

 

                                + Parkinson's disease:  A progressive nervous

                                                disease occurring most often after the

                                                age of 50, associated with the

                                                destruction of brain cells that produce

                                                dopamine, and characterized by

                                                muscular tremor, slowing of movement,

                                                partial facial paralysis, peculiarity of

                                                gait and posture, and weakness.

 

                        ^ Serotonin:  a neurotransmitter involved in sleep,

                                            depression, and memory.  An undersupply

                                            of norepinephrine and serotonin may

                                            result in depression.

 

Types of Neurotransmitters Handout

 

        - neuron activity: each neuron is either "on" or "off" depending

                                   on the neural activity around it.

 

                * intensity: The intensity of activity in each neuron

                                 depends on how many other neurons are acting

                                 on it.

 

        - Neural impulse destination: The actual destination of

                           nerve impulses produced by an excited neuron, as

                           they travel from one neuron to another, is limited by

                           what tract in the nervous system they are on.

 

                * ascending tracts: carry sensory impulses to the brain.

 

                * descending tracts: carry motor impulses from the brain.

 

        - 3 types of neurons:

 

                * afferent: also called sensory neurons they relay messages

                                 from the sense organs (including eye, ear, nose,

                                 and skin) to the brain.

 

                * efferent: also called motor neurons, they send signals

                                 from the brain to the glands and muscles.

 

                * interneurons: carry impulses between neurons in the body.

 

2 types of actions: and a nervous system for each.

          

     1.) voluntary: what you choose to do like lifting your hand

 

     2.) involuntary: happen automatically like heartbeat and

                        breathing

 

Somatic Nervous System (SNS): the part of the peripheral nervous

                                                    system that controls voluntary

                                                    movement of skeletal muscles.

                                                        (Soma is Latin for body.)

 

Autonomic Nervous System (ANS): the part of the peripheral nervous

                                                        system that controls internal

                                                        biological functions.

 

It should be noted that the autonomic nervous system is always working. It is not ONLY active during "fight or flight" or "rest and digest" situations. Rather, the autonomic nervous system acts to maintain normal internal functions and works with the somatic nervous system. The ANS regulates:

 

                Muscles

                     in the skin (around hair follicles; smooth muscle)

                     around blood vessels (smooth muscle)

                     in the eye (the iris; smooth muscle)

                     in the stomach, intestines and bladder (smooth

                    muscle)

                     of the heart (cardiac muscle)

 

                Glands

 

        - 3 parts of the ANS: sympathetic, parasympathetic and enteric

                                           nervous systems.

 

                * Sympathetic nervous system: part of the ANS that

                                      prepares the body for dealing with

                                      emergencies or strenuous activity. 

 

                                ** This what kicks in your "fight or

                         flight" response.

 

                        ^ 6 actions:

                                1.) It prepares the body for dealing with

                                   emergencies or strenuous activity.

                                2.) It speeds up the heart to hasten the supply of

                                   oxygen and nutrients to body tissues.

                                3.) It constricts some arteries and relaxes others

                                   so that blood flows to the muscles, where it is

                                   most needed in emergencies and strenuous

                                   activity.

                                4.) It increases the blood pressure.

                                5.) It increases respiration.

                                6.) It suspends some activities (like digestion).

 

                * Parasympathetic nervous system: works to conserve

                                       energy and to enhance the body’s ability to

                                       recover from strenuous activity.

 

                        - 4 actions:

                                1.) It works to conserve energy and to enhance the

                                   body’s ability to recover from strenuous

                                   activity.

2.) It reduces the heart rate.

3.) It reduces blood pressure.

4.) It works to bring the body back to its normal

     resting state.

 

                * Enteric nervous system: regulates the normal activity

                                        of the digestive system and

                                        prepare it for whatever its

                                        future may hold.

 

        - "autopilot":  All of this takes place automatically.  Receptors

                              are constantly receiving messages that alert the

                              autonomic nervous system to carry out routine

                              activities.

 

        - without one's ANS:  We would have to consciously think about

                                                                    doing even the most basic of activities…

                                          and that would include breathing!

 

 

 

6-2: Studying the Brain

 

Early Greeks: were not really impressed with the brain.

 

        - brain's function: was to cool the blood.

 

        - heart's function: was the source of feelings and thoughts.

 

        - Hippocrates: Ancient Greek philosopher who is considered to

                      be the “father of medicine”, believed       

                    somewhat differently than most.  He believed

                    diseases were caused by natural, not

                    supernatural (evil spirits) causes.

 

                * effect of brain injuries:  observed the effect of head

                                                         injuries on people’s thoughts and

                                                         actions and noted,

 

                * quote: “[F]rom the brain, and from the brain only, arise

                            our pleasures, joys, laughter and jests, as well as

                            our sorrows, pains, griefs and tears. Through it, in

                            particular, we think, see, hear. . . . Eyes, ears,

                            tongue, hands and feet act in accordance with the

                            discernment [judgment] of the brain.”

 

                        ^ meaning: There is more going on in the brain than

                                        what most Greeks thought.

 

3 main parts of the brain: hindbrain, midbrain, and forebrain.

 

        - hindbrain: a part of the brain located at the rear base of the

                          skull that is involved in the basic processes of life

                          such as sleeping, waking, coordinating body

                          movements, and regulating vital reflexes.

 

                * 3 parts: cerebellum, medulla, and the pons.

 

                        ^ cerebellum: a part of the brain that helps control

                                            posture, balance, and voluntary

                                            movements.

 

 

                        ^ medulla: part of the brain that controls breathing,

                                       heart rate, and a variety of reflexes.

 

                     + contents: contains the respiratory, vasomotor

                                   and cardiac centers, as well as

                                   many mechanisms for controlling

                                   reflex activities such as coughing,

                                   gagging, swallowing and vomiting

 

                        ^ pons: functions as a bridge between the spinal cord

                                  and the brain.  It is also involved in producing

                                  chemicals the body needs for sleep.

 

        - midbrain: serves as the nerve pathway of the cerebral

                         hemispheres and contains auditory and visual reflex

                         centers.

 

                * action: integrates sensory information and relays it

                             upward.

 

        - Brainstem: The lower extension of the brain where it connects

                            to the spinal cord.

 

                * 5 neurological functions located in the brainstem:

                1.) breathing

                2.) digestion

                3.) heart rate

                4.) blood pressure

                5.) arousal (being awake and alert)

 

     ** Notice these are functions necessary for survival.

 

           * Cranial nerves:  Most of the cranial nerves come from

                               the brainstem.

 

           * as a pathway: The brainstem is the pathway for all

                              fiber tracts passing up and down from

                              peripheral nerves and spinal cord to the

                              highest parts of the brain.

 

^ brain death: The brain can survive for up to about

                 4-6 minutes after the heart stops.

                 If CPR is started within six minutes

                 of cardiac arrest, the brain may

                 survive the lack of oxygen. After

                 about 6 minutes without CPR,

                 however, the brain begins to die.

 

                 Brain death is defined as the

                 irreversible loss of all functions of

                 the brain.

 

     It can be determined in several ways.

 

     1.) No electrical activity in the brain; this is

          determined by an EEG.

     2.) No blood flow to the brain; this is

          determined by blood flow studies.

     3.) Absence of function of all parts of the

          brain - as determined by clinical

          assessment.

                - no movement

                - no response to stimulation

                - no breathing

                - no brain reflexes.

     4.) The patient can be given 1 mg of atropine

          IV. In the patient with an intact brain,

          atropine will dramatically increase the

          patient's heart rate. In a brain-dead

          patient, atropine will not influence heart

          rate.

 

                * Reticular activating system: serves to alert the rest of

                                          the brain to incoming signals and is involved

                                          in the sleep/wake cycle.

 

        - Forebrain: the largest part of the brain that covers the brain’s

                            central core, consisting of left and right

                            hemispheres, which are connected by a wide band of

                            fibers, the corpus callosum.

 

Thalamus (3 actions):

        1.) It integrates sensory input. 

        2.) It is a relay station for all the information that travels to and

            from the cortex.

        3.) All sensory information with the exception of smell enters

             here.

 

Hypothalamus (4 things it controls): It regulates the ANS.

        1.) Controls functions such as hunger, thirst, and sexual behavior. 

        2.) Controls the body’s reactions to changes in temperature.

        3.) Monitors the amount of hormones in the blood.

        4.) Sends out messages to correct imbalances.

 

"new brain": refers to the cerebral cortex.

 

"old brain": Subcortex and the brain stem.  We share this with

              animals.

 

Examples to describe new and old brain:  Peach and peach pit

                                               Mushroom

 

Cerebrospinal fluid: The entire surface of central nervous system

                       is bathed by a clear, colorless fluid called

                       cerebrospinal fluid (CSF). The CSF is

                       contained within a system of fluid-filled

                       cavities called ventricles.

 

     - 4 functions

 

           1.) Protection: the CSF protects the brain from damage

                            by "buffering" the brain. In other words,

                            the CSF acts to cushion a blow to the

                            head and lessen the impact.

 

           2.) Buoyancy: since the brain is immersed in fluid, the

                           net weight of the brain is reduced from

                           about 1,500 gm to about 50 gm.

                           Therefore, pressure at the base of the

                           brain is reduced.

 

           3.) Excretion of waste products: the one-way flow from

                           the CSF to the blood takes potentially

                           harmful metabolites, drugs and other

                           substances away from the brain.

 

           4.) Endocrine medium for the brain: the CSF serves to

                           transport hormones to other areas of the

                           brain. Hormones released into the CSF can

                           be carried to remote sites of the brain

                           where they may have some action.

 

Cerebral cortex: gives you the ability to learn and store complex and

                           abstract information, and to project your thinking

                           into the future.  All of the functions of the

                   cerebral cortex are not fully understood.

 

        - size: about 80% of the brain's weight.

 

Limbic system: is composed of a number of different structures in

                        the brain that regulate our emotions and motivations. 

 

        - 4 parts: hypothalamus, amygdala, thalamus, and hippocampus.

 

Amygdala: controls violent emotions such as rage and fear.

 

Hippocampus: is important in the formation of memories.

 

-        if damaged: it would be difficult to form new memories.

 

Cerebrum:  is the site of your conscious thinking processes, yet it is

                  less than one-fourth inch thick.

 

Hemispheres of the brain: You have two hemispheres or sides to your

                                          brain.  Each hemisphere contains half of

                                          each of the four lobes of the brain.

 

        - control:  The left hemisphere controls the right side of your

                        body, and the right hemisphere controls the left side

                        of your body.

 

Corpus callosum: the band of fibers that connect the cerebral

                           hemispheres.  It carries messages to and from the

                           hemispheres.

 

Lobes: the different regions into which the cerebral cortex is

           divided.

 

        - Occipital: where visual signals are processed.

 

                * controls: everything optic.

 

                * if damaged: can cause visual problems.  A blow to the back

                                     of the head can cause serious damage to the

                                     optic nerve.

 

        - Parietal: is concerned with information from the senses from all

                        over the body (body sensation).  It is concerned with

                        sense of touch, differentiation (identification) of size,

                        shapes, and colors, spatial perception, and visual

                        perception.

 

        - Temporal: is concerned with hearing, memory, understanding

                           language (receptive language), organization,

                           sequencing, emotion, and speaking. 

 

     - Frontal: controls personality, planning for future

                  action, emotional control, attention, concentration,

                  creativity, initiation, problem solving, judgment,

                  self-monitoring, motor planning, organization,

                  mental flexibility, speaking (expressive language),

                  impulse control (inhibition of behavior), awareness

                  of abilities and limitations, and the ability to

                  censor thoughts and ideas.

 

           * This is the lobe that sustains the most injuries.

 

3 ways we find out what parts of the brain control:

- observation

- accidental or purposeful damage an area of the brain

- use of chemical or electrical stimulation to various areas

 

Phrenology: the study of the structure of the skull to determine

              an individual's character, personality and mental

              capacity.  (They felt the bumps on your head to

              figure out what "type" of person you were.)

 

     - how it advanced the understanding of brain functions:

                 It did advance the notion that the brain is the

                 seat of character, emotions, perception, and

                 intelligence and that different parts of the

                 brain are responsible for different mental

                 functions.

 

     - Pseudoscience: a false science

 

     - Franz Joseph Gall: founder of phrenology

 

     - date: late 1700s

 

     - 3 theories on phrenology:

     1.) Believed certain traits were in specific areas of the

          brain where ever there was a bump on the skull.

     2.) A less developed a trait showed as an indentation

     3.) Anyone's personality could be charted by studying

          bumps on the head

 

     - as a scam: Phrenology was a scam but very popular.

 

- use in 1860:  In fact, in the election of 1860, there were

                  even campaign ads describing the candidate's

                  phrenological charts.

 

Amount of brain tissue allotments: The number of touch sensors in a

                       body part determines its sensitivity, and, along with

                       the complexity of the part’s movement, governs the

                       amount of brain tissue associated with the part.

 

        - example: The touch and movement of the hands involve more

                         brain area than the more limited calves.

 

Can the brain feel pain?  No, because there are no receptor cells

                             in it.  You are even kept "awake" for

                             some brain surgeries.

 

Somatosensory cortex: receives information from the touch sensors.

 

Motor cortex: sends information to control body movement.

       

        - division: is also divided according to need. The more

                       sophisticated the movements (such as those used in

                       speaking), the bigger the brain area involved in their

                       control.

 

Association areas: mediate between the other areas.

 

        - 2 actions:

                1.) Does most of the synthesizing of information.  

                2.) Turns sensory input into meaningful information.

 

Right and left hemispheres: most information about properties

                                            of the left and right hemispheres is

                                            misinterpreted.

 

        - popular ideas: have oversimplified the properties of the two

                                hemispheres.

 

                * reality: In reality, the left and right sides complement and

                              help each other.

 

        - as mirror images: Each of the four lobes is present in both

                                      hemispheres.

 

        - function of corpus callosum: carries messages back and forth

                               between the two hemispheres to jointly control

                               human functions.

 

        - how connected: Each hemisphere is connected to one-half of

                                   the body in a crisscrossed fashion.

 

Left hemisphere (5 points):

        1.) Controls the movements of the right side of the body.

        2.) For most people, the left side of the brain is where speech is

             located.

        3.) mathematical ability

        4.) calculation

        5.) logic.

 

Right hemisphere (9 points):

        1.) Controls the left side of the body.

        2.) more adept at visual ability

        3.) spatial relations

        4.) Perceptual tasks are mostly processed here.

        5.) Recognizing patterns

        6.) Music

        7.) Art

        8.) Creativity

        9.) Intuition

 

Recent studies have shown that men convicted of violent crimes are more likely to have abnormalities of their frontal lobes and their right hemispheres.

 

Dyslexia: is a common reading disorder that is strongly linked to

           differences in brain function.  It can be perceptual in

           nature or a problem with processing the information.

 

     - Early labels: Poor readers were labeled as lazy or slow.

 

     - Today: we recognize that dyslexics’ brains function

                differently. Several recent studies indicate that

                dyslexics use more of their brain area to complete

                simple language tasks.

 

     - Imaging techniques: PET scans and MRIs assist researchers

                               in explaining how dyslexics’ brains

                               function.

 

     - Genetics: Researchers are also exploring a genetic link that

                   may indicate that dyslexia is largely an inherited

                   trait.

 

Left-brain characteristics: likes facts, logic, arithmetic, being in  

                               control of situation, have serious

                               approach

 

     - Strengths: organized, get things done, positive attitude for

                     goals, love competition.

 

- Problems: can be narrow-minded, see the "parts" but miss

              the "whole", make impulsive decisions, not too

              fond of change.

 

Right-brain characteristics: do several things at once,

                   spontaneous, impulsive, create new concepts,

                   imaginative, they like music, dance, humor,

                   laughter, fun, an informal environment, art, and

                   creativity, they forget about time

 

 

     - Strengths: they know how to have fun, very musical, think

                     in patterns to develop ideas, creative, and they

                     have a strong short-term memory

 

     - Problems: can fail to get things done, be impulsive, go

                   blank (especially under pressure).

 

Left and Right Brain Characteristics Handout

 

L/R Handedness v L/R BrainedNot the same thing. 

 

Right-handed children and brain development: Right-handed

                   children are genetically predisposed to develop

                   verbal left hemispheres, but the actual

                   specialization occurs over the years. 

 

In brain injury: This is why little kids that sustain a head injury

             can get better faster, and progress more, than adults

             in the same situation can.

 

     - For example speech: If a child suffers damage to

             the left hemisphere, the right will take over the

             function of speech.  The child may learn more slowly

             than other kids, but he or she will learn to speak

             again. However, almost all adults who suffer damage

             to the left hemisphere have extreme difficulty

             speaking, if they can speak at all.

 

 

The clear difference between the hemispheres: applies primarily

                                                to right-handed people. 

 

     - Right-handedness: Righties have significant differences

                             between the hemispheres - their

                             left is much more developed.

 

     - Left-handedness: Lefties have less of a dramatic

                            difference between the hemispheres

                            because they have to live in a

                            "right-handed" world.

 

     - % Of right-handed people worldwide: 90%

 

     - Herron (1976): said that left-handed people are truly

                          discriminated against by having to live in a

                          "right-handed world".

    

          * examples of left handed discrimination: doorknobs,

                          manual transmissions, pencil sharpeners,

                          light switches, spiral notebooks, student

                          desks

 

Stroke Handout and Main Types of Stroke Diagram 

    

Effect of a Stroke: Thus a stroke that causes damage to the

                        right hemisphere will result in numbness or

                        paralysis on the left side of the body.

 

     - In right handed people: the left hemisphere usually controls

                                   language and the right is involved in

                                   spatial tasks, so if he "stroked" on

                                   the left there would be numerous

                                   verbal issues.

 

Epilepsy:  Since the brain uses electrochemical energy, any disruption

                of the electrical processes in the brain will cause abnormal

                functioning. In this disease, neurons in the cerebral

                hemispheres misfire and create abnormal electrical

                activity.

 

                People with this disease have seizures that happen

                repeatedly. It is a bit like an electrical brainstorm.

 

                 The seizure prevents the brain from interpreting and

                 processing incoming sensory signals (like visual,

                 somatosensory and auditory information), and controlling

                 muscles.  That is why affected people may fall down and

                 twitch. 

 

                 This is a fairly common neurological disorder, and occurs in

                 about 1 in every 100-200 people.

       

     - 3 ways epileptics have been viewed in history

                1.) Believed to be possessed by evil spirits

                2.) Presumed to be insane

                3.) Assumed to be unintelligent.

 

           * discrimination:  They were discrimination because of

                               their ailment and the way it affects

                               their behavior; said to be unfit for

                               employment.

 

Epilepsy Handout

 

Split-brain surgeries: surgery to separate the brain hemispheres

                originally used to lessen the number and severity of the

                epileptic seizures. The person has two brains that operate

                independently of each other.  Since the corpus callosum is

                severed, there no longer is any communication between the

                hemispheres.

 

        - Kalat, 2001: found that separating the brain hemispheres

                              lessens the number and severity of the seizures.

 

        - how brain works after a surgery: The person has two brains

                                         that operate independently of each other.

 

        - communication between hemispheres:  Since the corpus

                                        callosum is severed, there no longer is any

                                        communication between the hemispheres…

                                        and that means that the seizure cannot

                                        cross over either.

 

Harriet Lees: an epileptic patient who's only hope was a split-brain

                      operation.

 

        - early life: For most of her life Lees’s seizures were mild and

                          could be controlled with drugs.

 

        - @25: seizures began to get worse.

 

        - @30:  having as many as a dozen violent seizures a day.

 

        - reasoning for a split-brain operation:  No other choice.  She

                                                  had little quality of life as she was.

 

        - 2 results for Lees:

                1.) Reduced the severity of seizures

                2.) She had fewer seizures

       

        - effects of the surgery: Despite the fact that patients who had

                                                this operation now had two functionally

                                                separate brains, they seemed

                                                remarkably normal.  (See page 164-165)

 

                                                 Individuals who have had split-brain

                                                operations remained practically

                                                unchanged in intelligence, personality,

                                                and emotions.

 

                * tactile stimulation: touch

 

PROFILES IN PSYCHOLOGY…pg 166

 

Roger Wolcott Sperry: Neurobiologist who became well-known in the

                                     specialized area of developmental

                                     neurobiology.

 

 

        - 7 points:

                1.) Became well-known in the specialized area of

                    developmental neurobiology.

                2.) Devised experiments that helped establish the means

                    by which nerve cells become wired in particular ways

                    in the central nervous system.

                3.) Is probably best known for his pioneering split-brain

                    research during the 1950s and 1960s, by devising a

                    number of experiments to test the functions of each

                    hemisphere of the brain.

                4.) Argued that two separate hemispheres of consciousness

                    could exist under one skull.

                5.) Pioneered the behavioral investigation of split-brain

                    animals and humans.

                6.) His experiments and techniques laid the groundwork for

                    constructing a map of mental functions.

                7.) In 1981 he became corecipient of the Nobel Prize for

                    Physiology and Medicine for his investigation of brain

                    functions.

 

        - quote: “In other words, each hemisphere [of the brain]

                      seems to have its own separate and private

                      sensations; its own perceptions; its own concepts;

                      and its own impulses to act. . . .Following surgery,

                      each hemisphere also has thereafter its own

                      separate chain of memories that are rendered

                      inaccessible to the recall processes of the other.”

 

                * meaning:  Split-brain patients really did have two brains,

                                 but they lived normal lives.. just their brains

                                 worked differently.

 

Brain mapping:  is the task of identifying the functions of different

                        regions of the brain.  It is one of the largest areas of

                        study in psychology and medicine right now.

 

        - physiological psychologists: same as below

 

        - psychobiologists: scientists responsible for the mapping of the

                                     brain’s fissures and inner recesses, and

                                     supplying others with fascinating information

                                     about the role of the brain in behavior.

 

4 methods used to study the brain:  recording, stimulating, lesioning,

                                                         and imaging.

 

Recording: ways to obtain electrical impressions of brain waves

                 and study them. 

 

        - electrodes: are wires that can be inserted into the brain to

                            record electrical activity in the brain.

 

                * process: By inserting electrodes in the brain, or onto the

                                scalp, it is possible to detect the minute

                                electrical changes that occur when neurons fire.

                                The wires are connected to electronic equipment

                                that amplifies the tiny voltages produced by the

                                firing neurons. Even single neurons can be

                                monitored.

 

        - Electroencephalograph (EEG): a machine used to record the

                                                         electrical activity of large

                                                         portions of the brain.

        - brain activity: the electrical activity of the brain rises and falls

                                 rhythmically.  These rhythms, or brain activity,

                                 occur because the neurons in the brain tend to

                                 increase or decrease their amount of activity in

                                 unison. Their intensity depends on the state of

                                 consciousness the individual is in during the

                                 EEG.

 

                * 3 states of consciousness examined: awake, drowsy, or

                                                                           asleep.

 

Stimulation: the use of electricity or chemical to set off the firing of

                    neurons in the brain.

 

        - 2 methods: electric and chemicals.

 

     - 2 "centers" in the brain: punishment and pleasure centers.

                                    One is painful and the other delivers feelings of

                euphoria -- like narcotics-- so the person likes the

                feelings he/she gets when this area is stimulated.   

                The “pleasure center” is what is being stimulated

                when we are engaging in activities we enjoy.

 

     - Olds and Olds (1965):  They implanted electrodes in the

                brains of rats.  The rat was then placed into a

                cage where he could press a lever, which would

                deliver a mild electrical current.  When the

                electrode was placed in the "pain" center, the rat

                would not touch the lever even if it meant not

                eating. But if the electrode was placed in the

                "pleasure" center, he would press the lever several

                thousand times an hour… and be higher than a kite.

 

        - Wilder Penfield: brain surgeon who stimulated the brains of his

                                    epileptic patients during surgery to determine

                                    what functions the various parts of the brain

                                    perform. 

 

                         He is considered a major pioneer in the

                         area of brain mapping.

 

                * use: to localize the malfunctioning part for which surgery

                         was required.

 

                * temporal lobe:  When he applied a mild electrical

                                           current to points on the

                                           temporal lobe of the brain, he

                                           could trigger whole memory

                                           sequences.

 

                        * Penfield & Rasmussen, 1950:  Did a similar study to

                                              Penfield's.  In it one woman heard a

                                              familiar song so clearly that she thought

                                              a record was being played in the

                                              operating room

 

        - 7 uses of stimulation:

                1.) Used with terminal cancer patients to relieve them of

                    intolerable pain without using drugs.

 

                                * Delgado, 1969: Found that a current delivered

                                      through electrodes implanted in certain areas

                                       of the brain may provide a sudden temporary

                                       relief.

 

                2.) Some psychiatrists have experimented with similar

                     methods to control violent emotional behavior in

                     otherwise uncontrollable patients.

                3.) Used in Parkinson's patients to control tremors.

                4.) Successfully used to treat essential tremor.

 

                                * Essential Tremor:  Essential tremor is a

                               movement disorder characterized by

                               the involuntary shaking of hands and

                               other body parts that is evoked by

                               intentional movements. It is unknown

                               why essential tremors occur, however

                               it is estimated to be as common as one

                               person in 20, and it is the most

                               common type of tremor and the most

                               commonly observed movement disorder.

                               Voluntary movements such as holding a

                               cup, fork, or pen make the tremor

                               worse. Signs and symptoms may

                               increase as your activity increases.

 

                5.) Used to treat Dystonia.

 

                                * Dystonia: a group of complex muscle disorders

                                  that involve involuntary twisting,

                                  repetitive movements that cause

                                  abnormal, sometimes painful

                                  positions. 

          

                                           ^ most common example: Writer's cramp

 

                6.) Experimental usage to treat chronic pain.

                7.) Beginning to be used experimentally to treat depression

                    that is resistant to all other forms of treatment.

 

Deep Brain Stimulation Handout

 

Lesions: a damaged area of brain, either done on purpose or by

             accident.

 

        - why: If the animal behaves differently after the operation,

                 they assume that the destroyed brain area is involved with

                 that type of behavior.

 

        - Kulver & Bucy, 1937: in one classic lesion study, two

                             researchers removed a certain area of the

                             temporal lobe from rhesus monkeys. Normally,

                             these animals are fearful, aggressive, and vicious,

                             but after the operation, they became less fearful

                             and at the same time less violent.

 

                * implication:  The implication was that this area of the

                                      brain controlled aggression. The relations

                                      revealed by this type of research are far

                                      more subtle and complex than people first

                                      believed.

 

Psychosurgery: brain surgery aimed at changing a person's

                  thoughts or actions by destroying a part of the

                  brain.  This is rarely used.

 

     - Prefrontal lobotomy: a surgical technique where a part of

                                the frontal lobes is destroyed in an

                                effort to change behavior or cure

                                "craziness".   About 50,000 of these

                                were done between 1935 and 1955. 

                                This was one of the only true

                                "treatments" science had discovered

                                for treating mental illnesses.

 

     - Side effects:  patients had trouble dealing with new

                         information, and problems in pursuing goals

                        (concentration), easily distracted.

 

 

     - Valenstein Quote: "There are certainly no grounds for

                             either position that all psychosurgery

                             necessarily reduces people to a

                             'vegetable status' or that it has a

                             high probability of producing miraculous

                             cures.  The truth, even if somewhat

                             wishy-washy, lies in between the

                             extreme positions.  There is little doubt,

                             however, that many abuses existed."

 

     - Effect of introduction of drug therapies: In the 1950's,

                   new drugs were introduced that altered the

                   chemical balances in the brain.  These have

                   helped people dramatically.

 

     -"New" surgeries: Surgeons now can destroy a small area

 

                           of the brain to control some behaviors. A

                           cingulotomy is one example.

 

     - National Association of Mental Health's stand: It argues

                  that “psychosurgery should only be used as a

                  last resort.

 

     - Current # of psychosurgeries per year: less than 100

                                                      per year

 

     - Commission for the Protection of Human Subjects of

        Biomedical and Behavioral Research: An 11 member

                  Congressionally appointed committee who studied                          

                  the use of psychosurgery and determined that

                  they did not approve of the older technique of

                  frontal lobotomy, but some of the newer

                  operations seem to work well.

 

     - Cingulotomy: the destruction of a major subcortical

                      structure, which seems to be very successful

                      in dealing with chronic pain and severe

                      depression. The nerve fibers destroyed are

                      part of a pathway important in emotions and

                      motivation. The surgery appears to eliminate

                      the discomfort and suffering the patient

                      feels, but does not  interfere with other

                      mental faculties such as thinking and memory. 

                      (It has also been experimentally used to treat

                       obsessive-compulsive disorder.)

 

Electroconvulsive therapy (ECT): Better know as "shock therapy". 

           It is only used to treat severe depression when meds

           and other psychotherapy treatments fail.  It sends an

           electrical current through the brain, which changes the

           brain chemistry. Approximately 110,000 Americans have

           this treatment per year.

 

           Although shock therapy has been performed for

           decades, researchers still don't know precisely how it

           works to combat depression.

 

     - The major theories:

           1.) Neurotransmitter theory: Shock works like anti-

                      depressant medication, changing the way brain

                      receptors receive important mood-related

                      chemicals, such as serotonin and dopamine and

                      norepinephrine.

 

           2.) Anti-convulsant theory: Shock-induced seizures teach

                      the brain to resist seizures. This effort to

                      inhibit seizures dampens abnormally active

                      brain circuits, stabilizing mood.

 

           3.) Neuroendocrine theory: The seizure causes the

                      hypothalamus, part of the brain that regulates

                      water balance and body temperature, to

                      release chemicals that cause changes

                      throughout the body. The seizure may release

                      a neuropeptide that regulates mood.

 

     4.) Brain damage theory: Shock damages the brain, causing

                      memory loss and disorientation that creates a

                      temporary illusion that problems are gone.

 

Tissue implants: There has been research in taking brain tissue

                   from donors (and aborted fetuses) and implanting

                   it in a patient's brain.  One day soon these could

                   be used to treat Parkinson's disease.

 

Parkinson's Disease is a progressive disorder of the central

                       nervous system. It is not a mental illness and

                       is not contagious or fatal.

 

     - treatment: It has not yet been possible to develop a cure

                     but most patients respond to medication and

                     physical therapy. Modern medication can help

                     most patients to enjoy an active and full life

                     span. A wide variety of drugs and therapies

                     can help to combat almost any problem that

                     occurs.

 

     - symptoms: There are five classic symptoms and signs,

                     although their presence and intensity varies

                     widely from patient to patient:-

 

                                1.) Tremor

                               2.) Rigidity

                               3.) Bradykinesia - Slowed ability to

                                           start and continue

                                           movements, and impaired

                                           ability to adjust the body's

                                            position.

                               4.) Gait (walking) disorder

                               5.) Loss of Balance

 

     - Dr. James Parkinson: was a general practitioner in London,

                                 England, first described "the shaking

                                 palsy". His report was published in

                                 1817 and contained the clinical

                                 symptoms.

 

     - rate: The condition occurs at the rate of 228 per 100,000

               people.

 

     -age of onset: usually begins between the ages of 50 and 65.

 

           * most affected age group:  It is much more prevalent in

                            the 60 to 69 age group but is sometimes

                            seen in patients under 40 years of age,

                            with an incidence of ten per 100,000.

 

     - cause: Parkinson's disease occurs when certain nerve cells,

               or neurons (in an area of the brain known as the

               substantia nigra) die or become impaired. Normally,

               these neurons produce an important brain chemical

               known as dopamine.

               

                     * Dopamine: is a neurotranmitter responsible

                                   for transmitting signals between

                                   the substantia nigra and the next

                                   "relay station" of the brain, the

                                    corpus striatum, to produce

                                    smooth, purposeful muscle activity.

 

                     * Loss of dopamine: causes the nerve cells of

                                the striatum to fire out of control,

                                leaving patients unable to direct or

                                control their movements in a normal

                                manner. Studies have shown that

                                Parkinson's patients have a loss of 80

                                percent or more of dopamine-

                                producing cells in the substantia nigra.

                                The cause of this cell death or

                                impairment is not known.

 

     - cure: It has not yet been possible to find a cure but most

              patients respond to medication and physical therapy,

              which can greatly alleviate the symptoms.

 

     - Modern medication: can help most patients to lead an

                              active, full life span. A wide variety of

                              drugs and therapies are available to

                              combat almost any problem that

                              develops.

 

           * goal of medication: The goal is to restore artificially

                                   the balance of dopamine, which is

                                   lacking in the brain. A combination

                                   of drugs can often improve the

                                   lifestyle of patients and keep them

                                   active both mentally and physically. 

 

     - Therapies: A special exercise program Physical therapy may

                    be specified by the doctor to increase muscle

                    mass and coordination. Speech therapy assists in

                    improving speech and swallowing. Occupational

                    therapy can improve manual dexterity and

                    activities of everyday life.

 

     - Research is proceeding vigorously. Understanding of the

                  complex processes that occur in the brain is

                  improving rapidly. Many new treatments are

                  becoming available to alleviate symptoms and

                  improve the quality of life for patients. 

 

Use of accidents in studying the brain: Psychologists can learn from

                       the tragedies when some people suffer accidents.

                      These accidents may involve the brain. Psychologists try

                      to draw a connection between the damaged parts of the

                      brain and a person’s behavior.

 

Phineas Gage: In 1848, he was a 25 year-old railroad crew

                 foreman from Vermont. Phineas was packing a load

                 of explosives into the earth, when the charge

                 accidentally exploded. An iron tamping rod that he

                 was using was propelled like a rocket and hit him in

                 the head. The rod was 3 feet 7 inches long and

                 weighed 13 pounds! It hit Phineas in the left

                 cheek, went straight  

                 through his skull and brain

                 and came out the top of

                 his head. (page 167)

                

 

 

 

 

 

 

     - aftermath: They cleaned out the terrible wound, and all

                     the time Phineas never lost consciousness. Over

                     the next couple of weeks, he bled severely,

                     became quite confused, and lost the sight in his

                     left eye. However, he lived for 13 more years,  

                     which astounded all those who treated him,

                     although he never lived a "profitable life", he

                     did manage to hold a job for a few years.  At

                     one time he was part of the "freak show" of a

                     circus.   

 

     - Effects: Surprisingly enough he was not killed and only

                  suffered minimal damage. His personality did

                  change dramatically - before the accident he was

                  a mature, trustworthy and dependable, and after

                  he was childish, and emotionally volatile, and anti-

                  social.

 

     - Damasio & Damasio, 1994: psychologists who examined Gage’s

                                                   skull (his family had donated it to

                                                   Stanford University) using the

                                                   newest methods available. They

                                                    reported that the tamping iron had

                                                    caused damage to parts of the

                                                    frontal cortex. They found that

                                                    damage to the frontal lobes

                                                    prevents censoring of thoughts and

                                                    ideas.

 

 

 

 

        - Frontal lobes control: personality, creativity, planning for

                  future action, emotional control, attention,

                  concentration, initiation, problem-solving,

                  judgment, self-monitoring, motor planning,

                  organization, mental flexibility, speaking

                  (expressive language), impulse control (inhibition of

                  behavior), awareness of abilities and limitations,

                  and the ability to censor thoughts and ideas.

 

Paul Broca:  French pathologist, neurosurgeon, and anthropologist,

                   (1824-1880) made important contributions to anatomy,

                    physiology and anthropology, and he was the founder of

                    modern brain surgery.

 

                     He had a young patient who could only respond with hand

                    gestures and the word “tan”… and he wanted to know why

                    this was so.

 

        - theory:  Broca theorized that a part of the brain on the left

                       side was destroyed, limiting the young man’s

                       communication processes… and he was right.

 

        - Broca's Area: the left side of the cortex, which is involved with

                                the production of speech.

 

6 types of brain imaging:

        1.) Computer axial tomography (CT scan)

        2.) Brain Electrical Activity Mapping (BEAM).

        3.) Event-Related Potentials (ERP)

        4.) Positron emission tomography (PET scan)

        5.) Magnetic resonance imaging (MRI)

        6.) Functional magnetic resonance imaging (fMRI)

 

Computer axial tomography (CT scan):  an imaging technique in which

                       low levels of x rays are passed through the brain and a

                       computer measures the amount of radiation absorbed

                       by the brain cells and produces a relatively good image

                       of the brain.

 

                - 2 uses: to pinpoint injuries and other problems in brain

                              deterioration

 

                - process: During a CAT scan, a moving ring passes X-ray

                                beams around and through a subject’s head.

                                Radiation is absorbed in different amounts

                                depending on the density of the brain tissue.

                                Computers measure the amount of radiation

                                absorbed and transform this information into a

                                 three-dimensional view of the brain.

 

Brain Electrical Activity Mapping (BEAM):  provides computer-

            generated maps of brain activity, with different colors

            indicating different levels of activity.

 

Event-Related Potentials (ERP): measure changes in patterns of

            brain activity in response to specific external stimuli.

 

Positron emission tomography (PET scan): an imaging technique used

                          to see which areas of the brain are being activated

                          while performing tasks.  Shows the glucose

                          consumption of the neurons.

 

           - glucose:  Blood sugar

 

                - process:  It involves injecting a slightly radioactive

                                solution into the blood and then measuring the

                                amount of radiation absorbed by blood cells.

                                Active neurons absorb more radioactive solution

                                than nonactive ones.

 

                - 2 uses:

                        1.) Researchers use the PET scan to see which areas

                            are being activated while performing a task

                        2.) PET scans show activity in different areas of the

                            brain when a person is thinking, speaking, and

                            looking at objects.

 

Magnetic resonance imaging (MRI): an imaging technique that passes

                                          non-harmful frequencies through the brain;

                                          a computer measures the interaction with

                                          brain cells and transforms this interaction

                                          into an incredibly detailed image of the

                                          brain (or body).

 

                - as a combination:  it combines the features of both CAT

                                              and PET scans.

 

                - 3 uses:

                        1.) to study the structure of the brain

                        2.) to identify tumors

                        3.) to find types of brain damage.

 

Functional magnetic resonance imaging (fMRI): used to directly

                              observe both the functions of different

                              structures of the brain and which structures

                              participate in specific functions.  This provides

                              high resolution reports of neural activity based on

                              signals that are determined by blood oxygen level. 

                              It actually detects an increase in blood flow to the

                              active structure of the brain.

 

                - 3 uses:

                        1.) observe functions of structures

                        2.) learn which structures participate in specific

                            brain functions.

                        3.) detects an increase in blood flow to the

                            active structure of the brain.

 

                - how it differs from a MRI: the fMRI does not require

                                                             passing radio frequencies

                                                             through the brain.

 

 

Brain damage:

 

     - 2 major causes of brain damage: Strokes and head injury

 

     - Brain death: occurs within 4-6 minutes.

 

     - Neurons begin to die within 2 minutes.

 

     - 2 reasons neurons die: lack of oxygen and over stimulation.

 

     - Effect of Magnesium: blocks transmission is synapses.  IF

                                 injected into brain it slows down the

                                 degenerative process and saves some

                                 nerve cells.

 

     - Effect of Insulin: slows activity down, and lowers body

                             temperature. This can delay, or prevent

                             damage from stroke.

 

           *** Exception to the rule - Hypothermia: a state of

                            coldness, which causes everything to

                            slowing down. A brain can survive longer

                            at a low temperature because it is using

                            less oxygen. The younger the patient, the

                            better his/her chance of survival.  There

                            have been cases of kids having little to

                            no brain damage from being immersed in

                            ice cold water for up to 20 or 30

                            minutes.

 

6-3: The Endocrine System

 

"Adrenaline rush": comes from a hormone secreted by the endocrine system called adrenaline or epinephrine.

 

Adrenaline/Epinephrine: hormone that is a natural stimulant.  It

                                       activates the sympathetic nervous system. 

                                        It helps a person generate extra energy to

                                        handle a difficult situation.

 

        - how it works:  The adrenal hormone declares an emergency

                                 situation to the body, requiring the body to

                                 become very active.

 

PSYCHOLOGY & YOU - Do you do this? pg 171

 

Human Ethology:  is the study of human behavior as it naturally

                            occurs.

 

        - tongue example:  According to ethologists, a tongue display acts

                 as a nonverbal sign that interaction is not desired. For

                 humans, the tongue displays seem to indicate that the

                 person does not want to be interrupted because of the

                 need to concentrate in a difficult situation.

 

2 communication systems in the body: Nervous system and the

                                                            endocrine system.

 

Endocrine System: a chemical communication system, using hormones,

                              by which messages are sent through the

                              bloodstream.

 

        - hormones: chemical substances that carry messages through

                           the body in blood.

 

                * # of: Scientists have discovered more than 30

                    different hormones in the human body.

 

                * 3 basic things hormones do:

                1.) regulate cell metabolism

                2.) control growth

                3.) control reproduction

 

        - 6 points on the endocrine system:

                1.) Hormones circulate throughout the bloodstream but are

                    properly received only at a specific site: the particular

                    organ of the body that they influence.

 

                        * endocrine glands: release hormones directly into the

                                              bloodstream; also called ductless glands.

 

                        * exocrine glands:  release their contents through small

                                                    holes, or ducts, onto the surface of

                                                    the body, or into the inside of the

                                                    digestive system.  

 

                                        ^ examples:  tear ducts, salivary glands, sweat

                                                          glands

 

                2.) Hormones have various effects on your behavior. They

                    affect the growth of bodily structures such as muscles

                    and bones, so they affect what you can do physically.

                3.) Hormones affect your metabolic processes; that is, they

                    can affect how much energy you have to perform actions.

                4.) Some hormonal effects take place before you are born.

                    Essentially all the physical differences between boys and

                    girls are caused by a hormone called testosterone.

 

                        * testosterone: hormone that helps decide the sex of a

                                               fetus, and is important for the growth

                                               of muscle and bone along with the

                                               growth of male sex characteristics.

 

                5.) Certain other hormones are secreted during stressful

                    situations to prepare the body for action.

                6.) Hormones also act in the brain to directly influence your

                     moods and drives.

 

        - 10 endocrine glands and basic effects (pg 172)

 

                1.) Hypothalamus: controls the pituitary gland, among other

                                            things.

                2.) Pineal gland: may affect sleep cycle; inhibits

                                         reproductive functions.

                3.) Pituitary gland: regulates growth and water and salt

                                              metabolism

                4.) Thyroid gland: controls the metabolic rate.

                5.) Adrenal cortex: regulates carbohydrate and salt

                                metabolism.

                6.) Adrenal medulla: prepares the body for action.

                7.) Pancreas: regulates sugar metabolism.

                8.) Ovaries (female): affects physical and sexual

                                                development

                9.) Testes (male): affects physical and sexual development.

                10.) Thymus gland: involved in immunity

 

 

        - pituitary gland: the center of control of the endocrine system

                                  that secretes a large number of hormones.

 

                * as the "master gland": it runs most of the endocrine

                                                     system.

 

        - Hypothalamus:

                1.) monitors the amount of hormones in the blood

                2.) sends out messages to correct imbalances.

                3.) Controls functions such as hunger, thirst, sexual

                    behavior, and the body’s reactions to changes in

                    temperature.

 

        - Hormones:  chemical substances that carry messages through

                            the body in blood.

 

                * 5 actions:

                        1.) They carry messages to organs involved in regulating

                           and storing nutrients so that despite changes in

                           conditions outside the body, cell metabolism can

                           continue on an even course.

                        2.) They also control growth

                        3.) They control reproduction.

                        4.) They control ovulation

                        5.) They control lactation (milk production) in females.

 

        - Thyroid gland: endocrine gland that controls the metabolic rate

                                 and produces the hormone thyroxine.

 

                * thyroxine:  stimulates certain chemical reactions that are

                                     important for all tissues of the body.

 

                * Hypothyroidism:  a disease caused by too little thyroxine,

                                             which makes people feel lazy and

                                             lethargic.

 

                * Hyperthyroidism:  a disease caused by too much thyroxine,

                                               which causes people to lose weight and

                                               sleep and to be overactive.

 

        - Adrenal glands:  become active when a person is angry or

                                   frightened.  

       

                        * "fight or flight" response: activation of your

                                                                sympathetic nervous system.

 

                * 6 actions:

                        1.) They become active when a person is angry or

                           frightened.

                        2.) They release epinephrine and norepinephrine into

                           the bloodstream.

                        3.) These secretions cause the heartbeat and breathing

                            to increase.

                        4.) They can heighten emotions, such as fear and

                             anxiety.

                        5.) These secretions and other changes help a person

                            generate the extra energy he or she needs to

                            handle a difficult situation.

                        6.) The adrenal glands also secrete cortical steroids.

                                        * cortical steroids:  help muscles develop and

                                                              cause the liver to release

                                                              stored sugar when the body

                                                              requires extra energy for

                                                              emergencies.

 

Handout on Anxiety Disorders

 

Anxiety is your body's reaction to a perceived, anticipated or imagined danger or threatening situation.

 

Many medical professionals believe that anxiety disorders may be due to an overactive sympathetic nervous system, and/or overactive adrenal glands.

 

        - sex glands: 2 types - male and female

 

                1.) testes:  produce sperm and testosterone which affects

                                physical and sexual development.

 

                        ^ testosterone:  male sex hormone

                                * Low levels of testosterone are also found in

                                females.

 

                                + importance: in the physical development of

                                                    males, especially in the prenatal

                                                   period and in adolescence.

 

                                + during the prenatal period: it helps decide the

                                                                            sex of a fetus.

 

                                + during adolescence:  is important for the growth

                                                                 of muscle and bone along

                                                                 with the growth of male sex

                                                                 characteristics.

 

                2.) ovaries: produce eggs and the female hormones estrogen

                                 and progesterone.

 

                        ^ 2 hormones secreted

                                + estrogen:  a general term for female steroid sex

                                                 hormones which are secreted by the

                                                 ovary and responsible for typical

                                                 female sexual characteristics.

 

                                + progesterone: a steroid hormone produced in the

                                                       ovary; prepares and maintains the

                                                       uterus for pregnancy.

 

                        ^ 3 points:

                                1.) These hormones also regulate the reproductive

                                   cycle of females.

                                2.) The levels of estrogen and progesterone vary

                                    throughout the menstrual cycle.

                                3.) These variances can cause premenstrual

                                    syndrome (PMS) in some women.

 

                                                + PMS: premenstrual syndrome

                                                        - PMS includes symptoms such as

                                                       fatigue, irritability, and

                                                       depression.

 

Hormones vs. neurotransmitters

 

        - how they are similar: Both effect the nervous system.

 

        - norepinephrine:  A substance, both a hormone and

               neurotransmitter, secreted by the adrenal medulla and the

               nerve endings of the sympathetic nervous system to cause

               blood vessel constriction and increases in heart rate, blood

               pressure, and the sugar level of the blood.  This

               neurotransmitter is also involved with memory and learning.

 

        - difference between:  When a chemical is used as a

                     neurotransmitter, it is released right beside the cell

                     that it is to excite or inhibit. When a chemical is used as

                     a hormone, it is released into the blood, which diffuses

                     it throughout the body.

 

                * example:  Norepinephrine is a hormone when it is secreted

                                 into the blood by the adrenal glands.

                                 Norepinephrine is a neurotransmitter, though,

                                 when it is released by the sympathetic motor

                                 neurons of the peripheral nervous system.

 

        - Snyder, 1985:  Found that hormones and neurotransmitters

                                  appear to have a common evolutionary origin.

 

                                  As multicellular organisms evolved, the system

                                  of communication among cells coordinated their

                                  actions so that all the cells of the organism

                                  could act as a unit. As organisms grew more

                                  complex, this communication system began to

                                  split into two more specialized communication

                                  systems.

 

                * 2 systems

                        One, the nervous system, developed to send rapid and

                       specific messages, while the other, involving the

                       circulatory system, developed to send slow and

                       widespread communication.

 

                        In this second system, the chemical messengers

                       evolved into hormones.

 

        - speed of transmission:  Neural (chemical/electrical) messages

                                               can be measured in thousandths of a

                                               second (about 250 mph), hormonal

                                               (chemical) messages may take minutes

                                                to reach their destination and weeks or

                                                months to have their total effect.

 

 

6-4: Heredity vs. Environment

 

role of genes:  Genes establish what you could be.

 

role of environment:  Environment defines the final product.

 

Heredity vs. Environment argument/debate:  People often argue about

                  whether human behavior is instinctive (due to heredity) or

                  learned (due to environment).

 

        - heredity:  is the genetic transmission of characteristics from

                          parents to their offspring.

 

        - reason for argument/debate: Many people assume that

                           something learned can probably be changed, whereas

                           something inborn will be difficult or impossible to

                           change. The issue is not that simple, however.

 

        - interaction of heredity and environment:  Inherited factors and

                             environmental conditions always act together in

                             complicated ways.

 

Nature vs. Nurture:  aka heredity vs environment.

 

        - Nature: refers to the characteristics that a person inherits;

                       his or her biological makeup.

 

        - Nurture: refers to environmental factors, such as family,

                        culture, education, and individual experiences.

 

 

Sir Francis Galton:  became one of the first to preach the importance

                               of nature in the modern era.

 

        - Heredity Genius:  a book in which he analyzed the families of

                                      over 1,000 eminent politicians, religious

                                      leaders, artists, and scholars.

 

                * date:  1869

 

        - Method of study: He read biographies.

 

        - His conclusion:  He found that success ran in families and

                                   concluded that heredity was the cause.

 

John Watson:  the founder of behaviorism, who emphasized the

                        importance of the environment.

 

        - Quote:  “Give me a dozen healthy infants, well-formed,

                       and my own specified world to bring them up in and I’ll

                       guarantee to take any one at random and train him to

                       become any type of specialist I might select—a doctor,

                       lawyer, artist, merchant-chief, and, yes, even

                       beggarman and thief, regardless of his talents,

                       penchants, tendencies, abilities, vocations, and race of

                       his ancestors”

 

        - Meaning:  Environment is the only factor that is important.

                      Genetics play only a small role.  Watson’s idea is

                          pretty extreme.

 

Genes:  the basic units of heredity.

 

        - 3 points:

                1.) They are reproduced and passed along from parent to

                    child.

                2.) All the effects that genes have on behavior occur

                    through their role in building and modifying the physical

                    structures of the body.

                3.) Those structures must interact with their environment

                    to produce behavior.

 

3 areas of genetic influence on human traits:

     1.) Cognitive abilities (like IQ)

    2.) Mental illness

    3.) Personality

 

Charles Darwin: English biologist who in 1859 published his theory of evolution. (in The Origin of Species)

 

     - 2 main ideas:

             1.) All animal species are related to one another

            2.) The structure of bodies and behavior patterns can

                 be distinguished and compared

 

His theory does not mean that humans do not possess unique qualities.  It does, however, make it possible to think of humans as members of a particularly complex, interesting species rather than as totally different from other animals.

 

Ethology: the study of animal behavior in its natural environment

 

     - 2 things Ethologists study: They study how the behavior

              patterns have evolved and changed and how they are

              expressed in humans.

 

Species-specific behavior: behaviors of characteristics of a

                               particular animal species

 

Stereotyped behaviors: patterns of responses that cannot change

                          readily in response to changes in the

                          environment

 

     - Effect of environment: These will work well only if the

                 environment stays as it was when the behavior  

                 pattern evolved.

 

Fixed action patterns: inflexible patterns of response. The animal

                          can only act one way. (Also called

                          stereotyped behaviors)

 

Instinct: a behavior that is inborn rather than learned.

 

** People often misuse the word instinct to refer to behaviors that have become automatic over a long period of practice.

 

Ethologists have found that animals are born with special sensitivities to certain cue in the environment, as well as with special ways of behaving.

 

Sign stimuli: cues in environment, which cause animals to respond

               in certain ways.

 

     - In humans: although instincts are less common and less

                     powerful in humans, there is evidence that some

                     stereotyped behaviors exist.  

 

     - Sign stimuli examples in humans: the parental instinct, and   

                                             the survival instinct.

 

 

Konrad Lorenz: Psychologist who did studies on learning and

     instincts.  He said that all humans possess the “parental      instinct” - A human baby (or any baby animal) can cause an      adult human to feel the need to take care of it.

 

Human ethology: study of human behavior as it naturally occurs.

 

Sociobiology: the study of the biological basis for social behavior.

 

     - 3 other areas of study:

           1.) biology

           2.) psychology

           3.) anthropology

 

     - Edward Wilson: Harvard zoologist published a book where

                          he defined the term “sociobiology”.

 

           * 2 ideas:

                1.) There are certain traits we share with animals.                2.) These behaviors are passed along genetically.

 

     - 3 ideas of sociobiologists:

 

           1.) They regard their discipline as the last phase of the

               revolution begun by Charles Darwin.

 

                * Natural selection: nature’s goal is individual

                                       survival and reproduction.

 

                Even though there are lots of examples where this

                may not be the case.

 

                * Soldier ants: will fight to the death to save the

                                  group from invaders.

 

                * Birds: will call out to each other if there is a

                         predator nearby, even though the warning

                         alerts the predator to the location of that

                         bird.

 

                * Dolphins: have been known to band together to

                             protect can injured companion on the

                             surface of the water where it can

                             breathe.

                * Humans:  Parents rescuing kids, EMS risking their

                             lives to save some one else, a soldier

                             sacrificing his/her life to save a platoon.

 

           2.) Sociobiologists fit all these acts of self-sacrifice

               into nature’s economy.  They explain that Altruism:

               (the unselfish concern for the welfare of others)

               itself favors genetic gain: the individual risks itself,

               but the results of this behavior is that other

               individuals who share its genes survive.

 

           3.) Sociobiology seeks to explain social behavior, even

               aggression, in terms of genetic advantage.

 

 

 

3 points on the effect of heredity on social behavior:

 

     1.) Human kind is flexible.

     2.) Genetic inclinations don't have to be always obeyed and

          sometimes shouldn't be.

     3.) The evolution takes place so slowly that we may still be

          inheriting behavior patterns that were adaptive in

          prehistoric times, but are no longer useful today.

 

Major contribution of sociobiology: has been to remind us that   genes do count, but that human beings have the capacity to learn a wide range of behaviors and unlearn those that cease   to be adaptive.

 

Back to heredity vs environment-- Now the problem is that most children are raised by their biological parents and in the same environment.  If this is the case, how can one tell which factor is most at work?  In order to truly get a clear picture of the importance of each, we need to study individuals who share the same genetic make up, AND are not raised in the same environment.  Solution:  Study twins.

 

Twin studies:  best way to look for genetic and environmental links.

 

Identical twins: develop from a single fertilized egg (thus, they are

                         called monozygotic) and share the same genes.

 

Fraternal twins:  develop from two fertilized eggs (thus, dizygotic),

                           and their genes are not more similar than those of

                           brothers or sisters.

 

Mirror image twins: are identical twins that result when a fertilized

                               egg splits later in the embryonic stage than usual,

                               typically from day 9 to 12. They tend to exhibit

                               characteristics with reversed asymmetry (e.g.,

                               one twin is left-handed and the other is right-

                               handed).  If this split happens much later than

                               this, then the twins can be co-joined.

 

Twins growing up in the same house share the same general environment, but identical twins also share the same genes.

So, if identical twins who grow up together prove to be more alike on a specific trait than fraternal twins do, it probably means that genes are important for that trait.

 

But what if identical twins are adopted into separate families? Then could we possibly tell if traits are genetic or environmental.

 

Thomas Bouchard: Psychology researcher at the University of Minnesota who studies twins. He is considered of the leading authorities on twins.  He has performed numerous studies comparing twins that were separated at birth and placed in adoptive homes to see the links between heredity and environment. 

 

        - University of Minnesota: It pays for the studies.

 

        - quote:  He says "that despite different social economic  

                                   backgrounds, twins share many common

                                   behaviors."

 

        - conclusion:  Many similarities in adopted twins suggest that

                            heredity may contribute to behaviors that we

                            normally associate with experience.

 

7 areas of similarity for twins separated at birth:

- Academic record

- Health

- Choice of occupation

- Sexual attraction

- Smoking/drinking/drug usage patterns

- Artistic abilities

- Musical abilities

- Athletic abilities

- Sexual orientation

- Naming of children/pets.

 

3 points researchers on heredity and environment:

        1.) Many researchers now believe that many of the differences

            among people can be explained by considering heredity as well

            as experience.

        2.) Contrary to popular belief, the influence of genes on behavior

             does not mean that nothing can be done to change the

             behavior.    

        3.) Although it is true that it is difficult and may be undesirable

             to change the genetic code that may direct behavior, it is

             possible to alter the environment in which the genes op