Download Role of the Nerve and Endocrine Understanding the Human Behavior

Role of nerve
regulation for
bechaviour
Central & peripheral
nervous system


The central nervous
system includes the brain
and the spinal cord.
Bundles of neuron axons
that carry information in the
peripheral nervous
system.
Motor Efferent Division

Can be divided further:
 Somatic nervous system
 VOLUNTARY (generally)
 Somatic nerve fibers that conduct impulses
from the CNS to skeletal muscles
 Autonomic nervous system
 INVOLUNTARY (generally)
 Conducts impulses from the CNS to smooth
muscle, cardiac muscle, and glands.
Somatic vs. Autonomic


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Voluntary
Skeletal muscle
Single efferent neuron
Axon terminals release
acetylcholine
Always excitatory
Controlled by the cerebrum


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

Involuntary
Smooth, cardiac muscle;
glands
Multiple efferent neurons
Axon terminals release
acetylcholine or
norepinephrine
Can be excitatory or
inhibitory
Controlled by the
homeostatic centers in the
brain – pons, hypothalamus,
medulla oblongata

Reflex

a simple, automatic, inborn response to a sensory stimulus
Brain
Sensory neuron
(incoming information)
Interneuron
Motor neuron
(outgoing
information)
Muscle
Skin
receptors
Spinal cord

Neural Networks

Neurons in the brain
connect with one
another to form networks

Inputs
Outputs

The brain learns by modifying
certain connections in
response to feedback
interconnected
neural cells
with experience,
networks can
learn, as feedback
strengthens or
inhibits
connections that
produce certain
results
computer
simulations of
neural networks
show analogous
learning


Sympathetic
nervous system branch of the
autonomic nervous
system that produces
rapid physical
arousal in response
to perceived
emergencies or
threats.
Parasympathetic
nervous system branch of the
autonomic nervous
system that
maintains normal
bodily functions and
conserves the body’s
physical
Autonomic Nervous System

2 divisions:
 Sympathetic
 “Fight or flight”
 “E” division
 Exercise,
excitement,
emergency, and
embarrassment
 Parasympathetic
 “Rest and digest”
 “D” division
 Digestion,
defecation, and
diuresis
The Central Nervous System


The central nervous system includes the brain
and the spinal cord.
This is the primary internal communication
network of the body; divided into the central
nervous system and the peripheral nervous
system.
The Brain Capturing a Thought
Specialized Cortical Regions
revealed with PET scan
As the human fetus develops, brain cells multiply, differentiate, and migrate
to their final locations.
By the fourth week of prenatal development, new neurons
are being generated at the rate of 500,000
per minute. By 24 weeks of prenatal age,
the brain has nearly its full complement
of neurons.


Saparate
cell

4th weeks
24 weeks

Newborn
child
After birth, the
neurons grow in size
and continue to
develop
new dendrites. Myelin
forms on neuron
axons in key areas of
the brain, such
as those involved in
motor control. Axons
also grow longer, and
the branching at the
ends of axons
becomes more dense.
By adulthood, the
fully mature human
brain
weighs about three
pounds.
The ‘Split Brain’ studies

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Surgery for epilepsy : cut
the corpus callosum
Roger Sperry, 1960’s
Special apparatus
 picture input to just
one side of brain
 screen blocks objects
on table from view
Verbal
left
hemisphere
Nonverbal
right
hemisphere
The ‘Split Brain’ studies

Picture to right brain

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can’t name the object
“What
“Using
“What
yourdid
left
did hand,
see?”
Pick you
up
you
what
see?”
you saw.”
left hand can identify by
touch
Picture to left brain


can name the object
left hand cannot identify
by touch
??
I saw an
Verbal
Verbal
apple.
leftleft
hemisphere
hemisphere
Nonverbal
right
hemisphere