Transcript Modules 5 and 6

Biological Bases
of Behavior
The Human Nervous System, Neurons, and
the BRAIN!!!
Modules 4-5
Phineas Gage
Phineas Gage !
In 1848, Gage, 25, was the foreman of a crew cutting a railroad bed in
Cavendish, Vermont. On September 13, as he was using a tamping iron to pack
explosive powder into a hole, the powder detonated. The tamping iron—43
inches long, 1.25 inches in diameter and weighing 13.25 pounds—shot skyward,
penetrated Gage’s left cheek, ripped into his brain and exited through his skull,
landing several dozen feet away. Though blinded in his left eye, he might not
even have lost consciousness, and he remained savvy enough to tell a doctor
that day, “Here is business enough for you.”
Gage’s initial survival would have ensured him a measure of celebrity, but his
name was etched into history by observations made by John Martyn Harlow,
the doctor who treated him for a few months afterward. Gage’s friends found
him“no longer Gage,” Harlow wrote. The balance between his “intellectual
faculties and animal propensities” seemed gone. He could not stick to plans,
uttered “the grossest profanity” and showed “little deference for his fellows.”
The railroad-construction company that employed him, which had thought him
a model foreman, refused to take him back. So Gage went to work at a stable in
New Hampshire, drove coaches in Chile and eventually joined relatives in San
Francisco, where he died in May 1860, at age 36, after a series of seizures.
Read more: http://www.smithsonianmag.com/history-archaeology/Phineas-Gage-Neurosciences-Most-Famous-Patient.html#ixzz2g62z2JoU
“I am a neuron”
• A nerve cell; the basic building block of the nervous
system
• NEURONS have 3 tasks:
1. Receive information
2. Carry information down its length
3. Pass the information on to the next neuron
• We have over 100 billion neurons! Most of the them are
in the BRAIN! 
Parts of the NEURON!
• Dendrites: the BRANCHING extensions of a neuron
that receive information and conduct impulses toward
the cell body (SOMA)
• Axon: the extension of a neuron through which neural
impulses are sent; covered in MYELIN SHEATH
• Axon terminals (buttons): the end point of a neuron
where neurotransmitters are stored
DO NOW
Hand in terms…make sure they
are numbered!!!
Take out notebooks! 
Electrochemical Communication
HOW DOES A NEURON FIRE???
1. Action potential: an impulse caused by
a neuron firing
2. Refractory period: after a neuron fires,
it needs to recharge before it can fire
again
3. Resting potential: when the neuron is
“charged” and waiting for another action
potential to start
Wait? Whattttttt?
How can I remember ALL of this neural
communication stuff????
Think about a toilet bowl!
Types of Neurons!
• Sensory neurons: nerve cells that
carry information received by the
senses TO the CNS
• Motor neurons: nerve cells that
carry information FROM the CNS to
the muscles and glands, and influence
their functioning
• Interneurons: nerve cells in the
brain and spinal cord responsible for
processing information
WAIT!
We know how
messages travel
DOWN the neuron
but then what???
How do neurons
communicate with
one another?
Communication between
Neurons
As the electrical impulse travels down to the
neuron’s axon terminals, a
NEUROTRANSMITTER is released
across the SYNAPSE to the receptor sites
on the dendrites of the next neuron.
Just do it? Or Nahhh…
Neurotransmitters either have an excitatory effect or an
inhibitory effect
EXCITATORY: GOOOOOOOOOOO!!!!!
INHIBITORY: STOP!!!!!!
Antagonist
A drug that blocks the effect
of a neurotransmitter
Agonist
A drug that boosts the effect
of a neurotransmitter
Examples:
ACh - curare
Examples:
ACh – black widow spider
venom
Human Nervous System
• Human nervous system is involved in thinking,
dreaming, feeling, moving
- regulates our internal functions
• TWO main parts:
• Central Nervous System (CNS) – consists of the
brain and spinal cord
• Peripheral Nervous System (PNS) – consists of the
nerve cells that send messages between the CNS and all
the parts of the body
Somatic Nervous System
• Transmits sensory messages to the CNS
• Activated by touch, pain, changes in temperature,
changes in body temperature
• Alerts us that parts of the body have moved or changed
positions
• Sends messages to the muscles and glands helping us
maintain posture and balance/skeletal system
Autonomic Nervous
System
•
•
•
•
1.
2.
Autonomic  “occurring involuntarily”
Regulates the body’s vital functions
EX: heartbeat, breathing, digestion, blood pressure
TWO divisions:
Sympathetic
parasympathetic
Sympathetic
• Activated when someone
is going into action;
prepares body for “fight
or flight”
- Suppresses digestion;
increases heart rate and
respiration, elevates
blood pressure
*Remember “S”
for stress
Parasympathetic
• Restores the body’s
reserves of energy
after an action
* Remember “P”
for peace
The BRAIN!!!!!!!!!!!!!!!
How do we STUDY it???
Scans that show STRUCTURE
• CAT scan: x-ray photographs
• MRI: uses magnetic fields and radio
waves to produce images
Scans that show FUNCTION!
• EEG: records electrical activity
• PET scan: visual display of activity;
glucose levels
• fMRI: shows activity (blood flow &
oxygen) AND images
Cerebral Cortex
• Newer neural networks within the
“cerebrum” – 2 hemispheres
• Covering like bark on a tree –
cerebral cortex
• Makes us distinctively human
Cerebral Cortex
• An intricate fabric of interconnected neurons that make
up the body’s ultimate control and informationprocessing center
- Longitudinal fissure: the long crevice that divides the
cerebral cortex into the left and right hemispheres
- Corpus callosum: large band of neural tissue that
connects the two hemispheres so they can communicate
LOBES of the BRAIN
• Frontal
• Parietal
• Temporal
• Occipital
FRONTAL
• It is concerned with
emotions, reasoning,
planning, movement,
and parts of speech. It
is also involved in
purposeful acts such as
creativity, judgment,
problem solving, and
planning.
• Motor cortex
• Broca’s area
PARIETAL
• They are connected with
the processing of nerve
impulses related to the
senses, such as touch,
pain, taste, pressure,
and temperature. They
also have language
functions.
• Sensory cortex
TEMPORAL
• The temporal lobes are
responsible for hearing,
memory, meaning,
and language. They also
play a role in emotion and
learning. The temporal
lobes are concerned with
interpreting and
processing auditory
stimuli.
• Wernicke’s area
OCCIPITAL
• The occipital lobe is
involved with the brain's
ability to recognize
objects. It is responsible
for our vision.
The BRAINSTEM
- Medulla
- Reticular formation
The THALAMUS
The CEREBELLUM
The Limbic System
- HYPOTHALAMUS
- HIPPOCAMPUS
- AMYGDALA
Review! (Answer in your
notebooks!)
1. How do neurons communicate?? (include
structures involved!)
2. What is action potential?! (TOILET)
3. AHHHHHHH! You scared me! My body is
STRESSED! What NERVOUS SYSTEM is being
activated? What part of the BRAIN is involved
in the emotion FEAR?
4. What LOBE deals with SENSORY information?
5. It’s sooooooo cold in here! What part of my
brain will regulate my body temperature??
**TAKE OUT LOBE COLORING from yesterday!**
LEFT vs. RIGHT
LEFT
Language…
Broca’s area: left frontal
lobe; speech
Wernicke’s area: left
temporal lobe;
comprehension
RIGHT
Spatial abilities
Art
Psychology’s Superheroes!!
BROC BRIGHT!
You get it right.
Pronouncing it will be outta sight.
Speech impediment, dyslexia…just a few to
name.
Even if you’re trying to learn a new language
the fact still remains the same.
Helping you perfect your language is the
name of my game.
What is a headache?
Concussions
Concussions in Sports
PITUITARY
• “master gland” controlled by hypothalamus
• Growth hormone – regulates growth of muscles,
bones, glands
• Prolactin – stimulates production of milk in nursing
women
• Oxytocin – stimulates labor
THYROID
• Thyroxin – affects the body’s metabolism
• Hypothyroidism – too little
• Hyperthyroidism – too much
ADRENAL
• Adrenaline & noradrenaline – help arouse body
and cope with stressful situations
• Adrenaline also plays a role in emotions…can
intensify fear and anxiety
TESTES & OVARIES
• Testosterone – role in development; primary and
secondary sex characteristics
• Estrogen/progesterone
Heredity
• Heredity – transmission of characteristics from
parents to offspring
- Plays a key role in development of traits
- Vital in transmission of physical traits: height, hair
texture, eye color
- Related to some extent in psychological traits
- shyness, leadership, aggressiveness, interest in
arts/crafts
- Research have found it is factor – anxiety,
depression, schizophrenia, bipolar, alcoholism
-
- normal humans : 46 chromosomes
- 22 of 23 pairs are similar between males/females
- 23rd pair – sex chromosome XX XY
- females have 2 X so they always pass an X; male
chromosome determines sex
- Abnormalities: Turner’s (single X); Klinefelter’s (extra
X); Down Syndrome (extra chromosome on the 21st
pair)
Nature vs. Nurture
• Nature  what is inherited
• Nurture  environmental factors
• Which has more of any influence???
• Should genetic counseling be mandatory???
Studies
• Kinship studies – 50% genes
• Twin studies – 100%; psychological disorders;
temperament
• Adoptee studies – more like biological parents or
adopted parents?
• Twins reared apart (studies!)
• Correlation coefficient for IQ – 0.69 for identical
twins reared apart; 0.88 identical twins living
together
Figure 3.27
Genetic relatedness. Research on the genetic bases of behavior takes advantage of the
different degrees of genetic relatedness between various types of relatives. If heredity
influences a trait, relatives who share more genes should be more similar with regard to that
trait than more distant relatives, who share fewer genes. Comparisons involving various
degrees of biological relationships will come up frequently in later chapters.
Figure 3.30
Twin studies of intelligence and personality. Identical twins tend to be more similar than
fraternal twins (as reflected in higher correlations) with regard to general mental ability and
specific personality traits, such as extraversion. These findings suggest that intelligence and
personality are influenced by heredity. (Intelligence data from McGue et al., 1993; extraversion
data based on Loehlin, 1992)