Transcript Biopsychology

Biopsychology
The Biological Basis of Behavior
Neurons: Structure
Dendrites
 Cell Body
 Axon
 Myelin Sheath
 Nodes of Ranvier
 Terminal Buttons

p. 45
Normally Functioning Nerves
The Synapse
Synaptic Vesicles
 Synaptic Cleft
 Receptor Sites
 Presynaptic membrane
 Postsynaptic membrane
 Neurotransmitters

p. 47
Neurotransmission
1.
2.
3.
4.
5.
Resting Potential (-70 millivolts)
Threshold ( greater than -70 mv)
Action Potential ( positive)
Hyperpolerization (less than –70 mv)
Resting Potential (-70 mv)
70
All or None Response
50
Membrane Potential
(mv)
Action Potential
30
10
-10
-30
Graded Potential
Threshold
-50
-70
-90
Hyperpolarization
Resting Potential
Time (ms)
Effects of Neurotransmitters

Excitatory

Inhibitory
Types of Neurotransmitters
Acetylcholine: ACh
 Norephinephrine: NE
 Dopamine: DA
 Serotonin:
5-HT
 Gamma-amino-butyric acid: GABA

Acetylcholine (ACh):
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

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
found through out the central nervous system,
autonomic nervous system, and all neuromuscular
junctions.
Excitatory
Involved in muscle action, attention, learning, and
memory
Too much: spasms
Too little: paralysis
Norephinephrine: NE
o
o
o
o
Synonymous with Adrenalin
Found in ANS
Excitatory
Responsible for getting “pumped up”
•
o
Fight or Flight Response
Eating behavior
•
Carbo-craving
Dopamine: DA




Reward system
Produced by neurons located in a region of the brain
called the substantia nigra.
Involved in pleasure, movement, attention, and
learning.
Degeneration of dopamine-producing neurons has
been linked with Parkinson’s Disease. Too much
dopamine is implicated in schizophrenia and
Tourette’s .
Serotonin: 5-HT

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Found in the brain and spinal cord.
Inhibitory
Plays a role in the regulation of mood and is control
of eating, sleep and arousal. Has also been
implicated in the regulation of pain and dreaming.
Destroyed by MAO
SSRI’s (Prozac, Zoloft)
Gamma-amino-butyric acid: GABA
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Found through out the brain and spinal cord, in very
high concentrations compared to other
Neurotransmitters.
Inhibitory
Is the major inhibitory neurotransmitter in the brain.
Abnormal levels of GABA have been linked to eating
and sleeping disorders.
Nervous System

Central
N.S.
Peripheral
Central
Brain & Spinal Cord

Peripheral
Somatic
Autonomic
Somatic
???
Autonomic
Parasympathetic
Sympathetic
Sympathetic
ParaSymp
p. 51
Autonomic Nervous System
Sympathetic
 Fight or Flight
1.
2.
3.
4.
Eyes open Wide
Mouth Goes Dry
Hr Increase
Start to Sweat
Parasympathetic
 Maintenance &
Refuel
1.
2.
3.
4.
Eyes constrict
Mouth Waters
Digestion
Blood away from
muscles
The Endocrine System
The Brain Stem
What is the difference between
a neurotransmitter and a
hormone?
Where are the seats of
consciousness?
Motivation & Emotion in the Brain
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Hypothalamus
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Limbic System
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Thalamus
Cortex
o
Parietal Lobe
o
Temporal Lobe
o
Occipital Lobe
o
Frontal Lobe
Brain Lateralization
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Right Hemisphere
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Left side of the body
Creativity
Math & Spatial tasks
Nonverbal - Emotion
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Left Hemisphere
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Right side of the body
Language
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Wernike & Broca
Q: What is the cause of ambidexterity?
A: Handedness (the preference to use one hand over the other) is speciesspecific. In humans, about 90% prefer to use their right hand. What does
this mean? Recall that the human brain is divided into a right and a left
hemisphere. Typically, the left hemisphere in humans is dominant.
We're not really sure why the left rather than the right (or both) becomes
dominant, but probably it reflects the early fetal environment, particularly
hormonal factors. Since the left hemisphere controls the right side of the
body, people with left hemisphere dominance will be right-handed. For lefthanders and for those who are ambidextrous (can use both hands with the
same level of skill), the right hemisphere tends to be dominant. Interestingly,
language, which typically is the province of the dominant hemisphere, is
equally likely to reside in either the left or right hemisphere for non-righthanded people. Those who are left-handed or ambidextrous also tend to
have a thicker corpus callosum (the bundle of fibers joining the two
hemispheres).
Genetics

Structure and Function
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Gene therapy
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Nature vs. Nurture