Neuroscience & Behavior
Myers, Chapter 2
Jacob S. Hillman
Why Study Biology



Everything psychological is simultaneously
biological.
Biological psychology provides insights into
numerous aspects of our lives, including sleep
and dreams, depression and schizophrenia,
hunger and sex, stress and disease, and many
others.
Early approach: Phrenology.
Phrenology
Images from:
http://pages.britishlibrary.net/phrenology/overview.htm
Structures of a Neuron
P. 38
How Neurons Communicate
• Everybody stand up.
• Yes. You too.
• Now follow the nice person’s
instructions…
How neurons communicate
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Neurons communicate by means of an
electrical signal called the Action
Potential.
Action Potentials are based on
movements of ions between the outside
and inside of the cell.
When an Action Potential occurs a
molecular message is sent to neighboring
neurons.
Neural Communication

Synapse [SIN-aps]



junction between the axon tip of the sending neuron and the
dendrite or cell body of the receiving neuron
tiny gap at this junction is called the synaptic gap or cleft
Neurotransmitters


chemical messengers that traverse the synaptic gaps
between neurons
when released by the sending neuron, neurotransmitters
travel across the synapse and bind to receptor sites on the
receiving neuron, thereby influencing whether it will
generate a neural impulse
Synapses
P. 40
Neurotransmitter Function
P. 42
Neurotransmitter Pathways
Serotonin Pathways
Dopamine pathways
P. 40
Nervous System
P. 43
Neurons
Types of Neurons
Sensory
Motor
Interneurons
Sensory Neurons
INPUT From sensory organs to the
brain and spinal cord.
Drawing shows a
somatosensory
neuron
Vision, hearing,
taste and smell
nerves are cranial,
not spinal
Sensory
Neuron
Brain
Spinal
Cord
Motor Neurons
OUTPUT From the brain and spinal
cord to the muscles and glands.
Sensory
Neuron
Brain
Spinal
Cord
Motor
Neuron
Interneurons
Interneurons
carry
information
between other
neurons. Only
found in the
brain and
spinal cord.
Sensory
Neuron
Brain
Spinal
Cord
Motor
Neuron
Peripheral Nervous System
► Somatic
► Autonomic
► Sympathetic
► Parasympathetic
Somatic System
► Nerves
to/from
spinal cord
 control muscle
movements
 somatosensory
inputs
Voluntary
and reflex
movements
► Skeletal Reflexes
Brain
Sensory
Neuron
► Both
 simplest is spinal
reflex arc
Skin receptors
Motor
Neuron
Interneuron
Muscle
P. 45
Autonomic System
► Two
divisions:
 Sympathetic
 Parasympatheitic
► Control





involuntary functions
heartbeat
blood pressure
respiration
perspiration
digestion
► Can
be influenced by thought and emotion
Sympathetic
► “Fight
or flight”
response
► Release adrenaline
and noradrenaline
► Increases heart rate
and blood pressure
► Increases blood flow
to skeletal muscles
► Inhibits digestive
functions
CENTRAL NERVOUS SYSTEM SYMPATHETIC
Brain
Dilates pupil
Stimulates salivation
Relaxes bronchi
Spinal
cord
Salivary
glands
Lungs
Accelerates heartbeat
Inhibits activity
Heart
Stomach
Pancreas
Stimulates glucose
Secretion of adrenaline,
nonadrenaline
Relaxes bladder
Sympathetic Stimulates ejaculation
ganglia
in male
Liver
Adrenal
gland
Kidney
Parasympathetic
► “Rest
and digest”
system
► Calms body to
conserve and
maintain energy
► Lowers heartbeat,
breathing rate, &
blood pressure
CENTRAL NERVOUS SYSTEM PARASYMPATHETIC
Brain
Contracts pupil
Stimulates salivation
Spinal
cord
Constricts bronchi
Slows heartbeat
Stimulates activity
Stimulates gallbladder
Gallbladder
Contracts bladder
Stimulates erection
of sex organs
Central Nervous System
► Brain
and Spinal Cord
Brain
Spinal
Cord
Brain Structures and their Functions
P. 57
So, what would happen if
 the two halves of your brain were
disconnectes??
References
• http://crackhouse.blogspot.com/2003_11_01_crackhouse_
archive.html
• http://diabetes.niddk.nih.gov/dm/pubs/complications_nerve
s/images/fourparts.gif
• http://pages.britishlibrary.net/phrenology/overview.htm
• Myers, D. (2005). Exploring Psychology (6th ed.). New
York: Worth Publishers.
• Myers, D. (2005). Instructor’s Resource CD-ROM: To
Accompany David G. Myers Exploring Psychology, 6th ed.
[Computer Software]. New York: Worth Publishers.
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CH02_illustration (D:\PowerPoints\Illustration PPTs)
Ch2 (D:\PowerPoints\Lecture PPTs)
nervous (D:\PowerPoints\Topic-based PPTs)
neurons (D:\PowerPoints\Topic-based PPTs)