Transcript Neuroscience, Genetics and Behavior

January 18, 2011
 You are driving down
the road, when
suddenly a car pulls
out in front of you.
How does your body
respond?
Neuroscience,
Genetics and Behavior
The Biological Basis for Behavior
Chapter 3
The Nervous System
 Our body’s primary
information system
 Brain and spinal cord
form the central nervous
system
 The Peripheral
Nervous system links
the central nervous
system with the body’s
sense receptors,
muscles and glands
Neurons
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Nerve cell
Cell body
Dendrites
Axon
Myelin Sheath
Axon terminals
How Neurons
Communicate
 The junction between
the axon tip of the
sending neuron and the
dendrite or cell body of
the receiving neuron is
called the SYNAPSE
 Synaptic gap or cleft-a
tiny gap between the
receiving neuron and
sending neuron
Neurotransmitters
 Chemical
messengers
released by axons
Neurotransmitters
 Acetylcholine-transmits between nerves and
muscles-Alzheimer’s disease
 Norephinephrine-sleep;bp;mood-depression
 Serotonin-mood;appetite;aggressiondepression and migraines
 Dopamine-involuntary body movementParkinson’s Disease, possibly schizophrenia
and addictions
 GABA(gamma-aminobutyric acid)-major
inhibitory transmitter in the brain-neuron loss
after stroke
2 more neurotransmitters
 Glutamate-major excitatory transmitter in
the brain (probably present in all the
nervous system)-neuron loss after stroke
 Endorphin-modulates sensory system,
including relief of pain and feeling of well
being-addictions
The Peripheral Nervous
System
 Somatic Nervous
System is voluntary
 Autonomic nervous
system is
involuntary divides
into sympathetic
and
parasympathetic
The BrainStem
 The brainstem-it begins
where the spinal cord
enters the skull and
swells slightly forming
the medulla
 Reticular Formation-a
finger-shaped network of
neurons, extends from
the spinal cord right up
to thalamus
Cerebellum
 Extends from the
rear of the brainstem
 Means little brain
 Coordinating
voluntary movement
Thalamus
 Jointed pair of eggshaped structures sit
atop the brainstem
 Brain’s sensory
switchboard
 Receives info from the
sensory neurons and
routes it to the higher
brain regions that deal
with seeing, hearing,
tasting, and touching
The Limbic System
 Donut shaped neural
system
 Controls emotions
and basic motives
Amygdala
 Almond shaped
neural clusters
 Influences
aggression
 Kluver and Bucy
surgically lesioned
part of a rhesus
monkey’s brain
including the
amygdala
Hypothalamus
 Lies just below the
thalamus
 Perform specific
bodily maintenance
duties
 It directs survival
skills-eating,
drinking, body temp.
 Helps govern the
endocrine system
The Cerebral Cortex
 An intricate covering of
interconnected neural
cells that form a thin
layer on the cerebral
hemispheres (like bark
on a tree)
 Our body’s ultimate
control and information
processing center
Four Lobes of the Cortex
 Frontal Lobes-behind
your forehead
 Parietal Lobes-at the
top and rear
 Occipital Lobes-at
the back of your
head
 Temporal Lobes-just
above your eyes
Motor and Sensory Cortex
Senses on the brain
Our Divided Brains
 The Brain divides its
mental functions of
speaking, perceiving,
remembering, and
thinking into sub
functions.
Corpus Callosum
 Wide band of axon
fibers that connect
the two hemisphers
Studies of the Corpus
Callosum
 Vogel and Bogen performed surgery on a
patient with epilepsy
 Patient acted normal afterward
personality and intellect hardly affected
 Sperry and Gazzaniga noticed patients
who had surgery developed changes in
perception and speech
Right and Left
Hemispheres
 Right-copying,
drawing, recognizing
faces, perceiving
differences,
expressing emotions
 Left-press agent or
the interpreter
Ways we study the brain
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Recordings (EEG)
Stimulation
Lesions
Accidents
Imaging
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CAT-X-ray
PET-brain activity
MRI-structure
fMRI-blood flow
Phineas Gage 1848
The Endocrine System
 The Endocrine Glands secrete hormones
(Chemical messengers that are produced in
one tissue and travel through the bloodstream
and affect other tissues including the brain)
 Hormones acting on the brain influence our
interest in SEX, FOOD, and AGGRESSION!
 CNS works like email, the Endocrine works like
snail mail.
 Endocrine messages last longer! Influence
many aspects of our lives.
Endocrine System
Genetics and Behavior
 Our genes provide
the blueprint for our
biology
 Psychologists ask
“Do genes provide
the blueprints for our
bodies and our
behaviors?”
Evolutionary Psychology
 “Are we shaped to make choices
because of the genes of our ancestors?”
Behavior Genetics
 Explore our differences
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Twin Studies
Adoption Studies
Heritability
Molecular genetics