Transcript 3 - smw15.org

PSY 190: General Psychology
Chapter 3:
Biological Psychology
“So why do we have to study
biology in a psych class?”

Let me use Phineas
Gage to help answer
this question…
“He was no longer Gage…”

Several different
angles of where the
rod passed through
his skull
There is a Phineas Gage display in the Warren
Medical Museum at Harvard University
This is what went through his brain (see
below)…
 3½ feet in length; 1¼ inch in diameter

Some history buffs travel to the
tiny town of Cavendish, VT
Biological Roots of Behavior

Franz Gall (1758-1828)
– Austrian physicist who
invented phrenology
– He felt that bumps on the
skull could reveal our mental
abilities and character traits.
– Introduced as being scientific
– Although, ill-fated theory was
laughed at by scientific
community of that day – it
may have had some validity
– Localization of brain
functions somehow hit the
mark
The Nervous System
Electrochemical communication system
that enables us to think, feel, and behave
 Complex beyond comprehension
 Although, human brains are more complex
our nervous systems and those of animals
operate in a similar fashion

Major Components

Neurons
– Rapidly respond to signals and quickly send
signals of their own
 Afferent – sensory neurons
 Efferent – motor neurons

Glial cells
– Help neurons to communicate, keep chemical
environment stable, secrete chemicals to help
restore damage, and respond to signals from
neurons – enable neurons to function
Axons

Function
– Carries signals away from the cell body
– Pass information along to other neurons, or to
muscles or glands
– Wrapped tightly with white, fatty myelin
 This insulates the axon
Synapse



Very small gap between
neurons
For communication to
occur between cells, the
signal must be
transferred across this
gap
Function
– Provides an area for the
transfer of signals
between neurons, usually
between axon and
dendrite
Dendrite

Function
– Detects and carries signals to the cell body

Type of Signal Carried
– The postsynaptic potential, which is an
electrochemical signal moving toward the cell
body
Receptors

Function
– Proteins on the cell membrane that receive
chemical signals

Type of Signal Carried
– Recognizes certain neurotransmitters, thus
allowing it to begin a postsynaptic potential in
the dendrite
Transmitting information
A neuron:

–
–
–
Receives signals form other neurons through
its branching dendrites and cell body
Then combines these signals in the cell body
And then transmits an electrical impulse
down its axon
Transmitting Information

Type of Signal Carried
– The action potential, an all-or-nothing
electrochemical signal that shoots down the
axon to vesicles at the tip of the axon,
releasing neurotransmitters
Neurotransmitters

Neurotransmitters are chemicals made by
neurons (nerve cells) and used by them to
transmit signals to the other neurons
– A chemical message telling the next cell to fire or not
to fire its own action potential
– More than 200 in our body all with different functions
 Lets briefly discuss some of the most important
ones…
Serotonin

Facilitates a relaxed,
sleepy feeling
– Tryptophan an amino
acid found in dairy
products and turkey is
converted into serotonin
in the body
Some Illnesses Associated With Serotonin
Depression
– Low levels
 Anxiety Disorders
– Low levels
 Obesity
– Low levels

Dopamine
High levels lead to pleasure
– Makes person feel happy and active
 Dopamine raises the body's temperature and
increases metabolic rate
 Gives you euphoric feelings and allows you to be
active
 Drug and alcohol abuse will block dopamine
receptors and therefore a person needs to take
more to get the same effect

Some Illnesses Associated With
Dopamine

Parkinson’s Disease
– low levels

Schizophrenia
– high levels

Tourette’s Disorder
– high levels
Norepinephrine
Stress hormone that plays a role in attention
and arousal
 Used by sympathetic nervous system to prepare
us for action

– Along with epinephrine underlies the fight-or-flight
response (increase HR, increase of glucose, increase
blood flow, etc.)
Some Illnesses Associated With
Norepinephrine

Depression
– low levels
 chronic stress depletes this neurotransmitter and
can lead to depression
 Note:
– Aerobic Exercise is found to protect the brain
from this depletion

Schizophrenia
– Specificially, akathisia (inner restlessness; inability to
sit still)
– high levels
Epinephrine (adrenaline)

Involved in energy and glucose metabolism
– Increases heart rate, contracts blood vessels, dilates
air passages

Used by sympathetic nervous system to prepare
us for action
– Along with norepinephrine underlies the fight-or-flight
response
Some Illnesses Associated With
Epinephrine

Depression
– low levels

Anxiety Disorders
– high levels
 ADHD
– high levels
Acetylcholine

Involved in voluntary movement, learning,
memory, and sleep
– Helps parasympathetic nervous system to slow
our heart rate
Some Illnesses Associated With
Acetylcholine


Alzheimer’s Disease (and other dementias)
– low levels
 Note:
– Unfortunately, drugs used to increase
acetylcholine to help restore normal levels appear
to have small effects on improving memory
Myasthenia Gravis
– autoimmune neuromuscular disease leading to
fluctuating muscle weakness and fatigability
– low levels
GABA

Inhibits excitation and anxiety
Illnesses Associated With
GABA

Anxiety disorders
– low levels
Huntington’s Disease
– low levels
 Huntington's disease is a hereditary disorder
characterized by memory loss, abnormal
movement and premature death
– GABA systems aren’t working and this
allows dopamine systems to run wild
 Epilepsy
– low levels

Glutamate
Main excitatory neurotransmitter in the
brain
 Very important in learning and memory

Illnesses Associated With
Glutamate

Depression
– Low levels in prefrontal cortex
Alzheimer’s Disease
– low levels in hippocampus
 Strokes
– high levels can cause neurons to die


ALS (Lou Gehrig’s Disease)
– high levels causes death in neurons in the
spinal cord and brainstem
Endorphins

Involved in pain reduction and pleasure
– They enhance the release of dopamine
– These natural opiates are released in response
to pain and vigorous exercise
Some Illnesses Associated With
Endorphins
Eating Disorders
– Low levels
 Drug addiction
– Low levels
 Use of artificial opiates can cause body to
stop manufacturing its own later leading to
withdrawal symptoms

Divisions of the Nervous
System

Consists of two systems
– Central Nervous System
 Brain and spinal cord
– Peripheral Nervous System
 Which connects the CNS to the rest of the
body
Organization of the Nervous System
Peripheral Nervous System

Two components:
– Somatic Nervous System
 Transmits sensory input to the CNS from
the outside world and directs motor output
– Autonomic Nervous System
 Controls glands and muscles of our internal
organs – “automatic pilot”
Autonomic Nervous System

Dual system:
– Sympathetic Nervous System
 Arouses the body
– Parasympathetic Nervous System
 Calms us down
Studying the Brain
Clinical observations
– Check trauma or disease
 Experimenting with the brain
– Electroencephalograph (EEG)
– Brain-Imaging Techniques
 Computerized axial tomography (CT scan)
 Positron emission tomography (PET scan)
 Magnetic Resonance Imaging (MRI)
 Functional Magnetic Resonance Imaging
(fMRI)

Cerebral Cortex

Makes us distinctively
human – much higher
developed than in
animals
– Motor Cortex – involved
in the conscious initiation
of voluntary movements
in specific parts of the
body including hand,
knee, foot and head
Fritsch and Hitzig
(1870)
 Delgado (1969)

Cerebral Cortex


Sensory Cortex
– receives information from our senses
 Visual cortex
– visual info
 Auditory cortex
– auditory info
 Somatosensory cortex
– info from skin
Association cortex
– involved in complex cognitive tasks associating words
with images
 Broca’s area (aphasia)
 Wernicke’s area (aphasia)
Recent Examples of Aphasia
Click on pictures above for video clips
How does the brain govern
behavior?

3 Principle layers of the brain:
– Hindbrain (Brainstem)
– Limbic System
 Hippocampus
 Amygdala
 Hypothalamus
– Cerebral Cortex
Hindbrain

The brain’s innermost region…
– Begins where the spinal cord enters the skull
and swells slightly forming the medulla
– Towards the rear of the brainstem is the
cerebellum – this is linked to memory and its
major function is muscular control
Limbic System
Limbic System

Hippocampus
– This structure plays a key
role in allowing us to store
new information
– Problems here may cause
Alzheimer's – these
individuals have trouble
processing declarative
memories
– Milner (1968): the classic
case of H.M.
– Only in 2008 (at the time
of his death at age 82),
was his name revealed as
Henry Molaison 
See article about H.M. on my website and read pp. 242-243 in textbook.
Limbic System

Amygdala
– Emotional control center of the brain – major
influence on aggression and fear
– Emotional memories as well
– Alzheimer’s ???
 Kluver and Bucy (1939)
 Demasio (1994)
Limbic System

Hypothalamus
– Major influence on hunger, thirst, body
temperature, and sexual behavior
 Olds and Milner (1954)
Brain Reorganization:
Synaptic Plasticity

Synaptic Plasticity
– Often when one area of the brain is damaged, other
areas may in time reorganize and take over its
function
 It is not uncommon for stroke patients who have
lost the ability to speak or to move a limb to regain
function after several weeks of convalescence
How does the brain recover?

Essentially what is occurring is a “remodeling” of
the cerebral cortex after an injury in which
sometimes a large part of it simply dies
– This is the exception and not the rule
 For example, not all stroke victims recover
Even better chances:
Plasticity in children

The brain has extraordinary powers of
reorganization, especially when damaged before
it is fully developed
Case Study:
Christina Santhouse
Click on picture for article 
The Split-Brain Phenomenon

Corpus Callosum
– Large band of neural fibers that connects the two
brain hemispheres

The two sides of our brains serve different
functions (lateralized or specialization of tasks):
– Left hemisphere: Language, math, logic
– Right hemisphere: spatial abilities, face recognition,
visual imagery, musical and artistic abilities, emotional
tasks.

This is the case for almost all right-handers
(about 96%) and about half of left-handers
Split-Brain Experiments
Vogel and Bogen (1961)
 Sperry and Gazzaniga

– Conducted many experiments from 1960’s
through the 1980’s
Important aspects of this divided
brain phenomenon
Information from left half of field of vision is
received only by your right hemisphere, and
information from the right half of your field of
vision is received only by your left hemisphere

–
Don’t get confused here as each eye receives sensory
information from both right and left visual fields. But
this information is only transmitted from a particular
visual field to a particular brain hemisphere
Important aspects of this divided
brain phenomenon

The left hemisphere receives information
from and controls movements of the right
side of the body, whereas the right
hemisphere receives input from and
controls movements of the left side of the
body
Important aspects of this divided
brain phenomenon

Hopkins (2006)
– Tests show that almost all right-handers (over
96%) process speech in the left hemisphere
– Left-handers are more diverse:
 70% process speech in the left hemisphere
 5% process speech in the right
hemisphere
 25% use both hemispheres about equally
The Split-Brain Phenomenon
FIELD OF VISION
LEFT
RIGHT
When the patient is
asked
“What do you see?”
They answer…
LEFT
HEMISPHERE
RIGHT
The Split-Brain Phenomenon
LEFT
FIELD OF VISION
RIGHT
When the patient is asked
“What do you see?”
They answer…
LEFT
HEMISPHERE
RIGHT
The Split-Brain Phenomenon
LEFT
FIELD OF VISION
RIGHT
The same patient who
has just said they could
not see the picture is now
asked to take their left
hand and touch the
‘happy face” picture…
What happens now???
LEFT
HEMISPHERE
RIGHT
The Split-Brain Phenomenon
LEFT
FIELD OF VISION
RIGHT
Now, with the object in the
patient’s hand, he/she is
asked “what is in your
hand”…what is their
answer this time???
LEFT
HEMISPHERE
RIGHT
Split Brain Videos
Click on pictures above for video clips
Severed Corpus Collusom: Video

1st scene:
– “Joe” is flashed words in his right field of vision
(“storm” and “piano”) and has no trouble saying them
– He is then flashed the word “phone” in the left field of
vision…and he can’t say it
– “didn’t see that”
– But when asked to draw a picture of what he saw
with his left hand…he draws a telephone but since its
still in his left field of vision he still can’t verbalize
what he just drew
Severed Corpus Callosum: Video

But then when asked to draw it with his
left hand but in his right field of vision…he
is able to say what he drew (“oh, phone”)
– Very interesting…
Severed Corpus Collusom: Video

2nd scene:
– Joe is flashed words simultaneously in both
fields of vision – “toad” in left field and “stool”
in right field…
– He can’t say “toad” but can draw it with left
hand
– He can say ‘stool” and by speaking it, he is
able to let the right hemisphere in on the
“secret”
Severed Corpus Collosom: Video

3rd scene:
– Again, two words simultaneously…”bell”
appears in his left field of vision and “music”
in his right field of vision
– When asked to point with his left hand to
what he saw, Joe points to a picture of a bell
but is not really sure why so he makes up a
story that seems to be plausible…he’s
basically trying to figure out what's going on
Severed Corpus Callosum: Video

Joe’s left hemisphere is trying to interpret what
is going on – trying to find a cause and effect
– Left hemisphere is responsible for making sense out
of the mystery
– According to Gazzaniga: “the left hemisphere is where
the action is”
Severed Corpus Callosum: Video

Final scene:
– Pictures are shown of faces made out of fruit,
meat, etc.
– Right hemisphere specializes in locating faces
and left is better at finding elements
involved…

So what happens?
– Right hemisphere sees it as a face and left
hemisphere sees it as a fruit
Split-Brain Operations Today

Effective medications have replaced this
drastic procedure
Nature or Nurture?

What influences
one’s behavior?
– The age-old debate:
 Is it genes or is it
the environment?
 An interaction?
Goldie Hawn and Kurt Russell
Kate Hudson
Principle of Genetics

Master plan for your body….
– 46 chromosomes
 23 chromosomes carried in the egg are
paired with 23 chromosomes brought to it
by the sperm
– Each is composed of a molecule called
DNA
 DNA is made up of thousands of
segments which are called genes
Principle of Genetics

Your sex is determined by the 23rd pair – the sex
chromosomes…
– From your mother always an “x” 
– From your father, you have a 50/50 chance of
receiving an x  making you a female (xx)
– From your father, you have a 50/50 chance of
receiving an y making you a male (xy)
 XX = female
 XY = male
Twin Studies

Monozygotic
– Identical twins
(one-egg)

Dizygotic
– Not identical
(fraternal)
twins
 Resemble one
another as
much as any
brother or
sister would
Nature or Nurture?

Question:
– Do identical twins who are adopted by
separate families act like one another more
than say two adopted children into the same
family who have no genetic influences?
 Lets look at some case study research to help us
determine this…
“The Jim Twins”

Bouchard (1979)
– Thomas Bouchard 
– University of Minnesota twin
studies – extraordinary
similarities between Jim
Springer and Jim Lewis
 Uncanny coincidences?
 Any limitations to this study?
Click on picture above for video clip
The Jim Twins

Tested at the Univ of Minnesota
– Intelligence
– Personality
– Heart Rate
– Brain waves
All virtually alike as the same person
tested twice
 Voice intonations and inflections were so
similar that they could not tell each other’s

Twins Oskar Stohr & Jack Yufe

Bouchard (1979)
– Part of Bouchard’s twins study…
 Oskar Stohl and Jack Yufe were raised in
environments with more obvious differences
Did these guys share a flushing
the toilet gene?


Oskar raised by Grandmother in Germany as a Catholic and
a Nazi
Jack raised by Father in the Caribbean as a Jew
– Share traits and habits galore
 Love spicy foods
 Sweet liquors
 Fall asleep in front of the TV
 Flush the toilet before using it
 Store rubber bands on their wrists
 Dip buttered toast in their coffee
 Stohr is domineering toward women and yells at his
wife as did Yufe before he and his wife separated
Evolutionary Psychology
These psychologists study ways in which
adaptation and natural selection are connected
with mental processes
 Men and women by nature must differ in their
optimal mating behaviors
– Women must be highly selective because
they are biologically limited in the number of
children they can bear and raise in a lifetime
– Men can father an unlimited number of
children and ensure their reproductive
success by inseminating many women

Gender Differences…

The differences typically found between
the sexes are small compared to the
similarities…
– But when it comes to casual sex…
 See next slides…
“I have been noticing you around
campus. I find you very attractive.”
 Clark & Hatfield (1989)
– In this study, students were approached by
another student of the opposite sex, who
uttered the above statement…
– This was followed by one of three invitations:
 “Would you go out tonight?” or
 “Would you come over to my apartment?” or
 “Would you go to bed with me?”
Percent Saying “Yes”
100
Men were even more
likely to say “yes” to
the sexual invitation
80
60
About half of
both sexes said
“yes” to the
date
40
20
0
Go Out
Go to Apt.
Go to Bed
Not a
single
woman
said “yes”
to the
sexual
invitation
The Burger King Study

Townsend &
Levy (1990)
– Who would you
prefer: a well-dressed
unattractive person or
a good-looking
person in a Burger
King outfit???

Burger King study:
– Townsend and Levy (1990) looked at the effects of male
status and ornamentation.
– First, males were pre-rated into 2 groups:
 Handsome versus homely
– Each were put into 1 of 3 costumes:
 Armani suit with Rolex (high status), white t-shirt
(medium status), or Burger King uniform (low status)
– They then did the same for females
Handsome
Homely
Armani suit
(high)
White t-shirt
(medium)
BK outfit
(low)
What do you think happened?