Communication between neurons occurs at the synapse a

Communication between neurons occurs at the synapse
A. Synapse – a junction between the axon terminals of one neuron and the dendrites or cell body
of another neuron (communication between two neurons occurs here)
1. Pre-synaptic vs. post-synaptic neuron
B. Firing neurons release neurotransmitters (chemical messengers) that cross the synapse
1. Neural impulse (the electrochemical discharge of a neuron)
C. Synaptic vesicles (sacs in the axon terminals that store the neurotransmitter)
1. Neural firing drives them to the synapse where they release their neurotransmitters
D. The neurotransmitter binds to the receptor site on the target (post-synaptic) neuron
E. Ion channels open – causes change in electrical potential of post-synaptic neuron
F. Types of neurotransmitters
1. Acetylcholine – movement, learning, memory
a. Disorder associated with malfunctioning - Alzheimer’s disease
2. Norepinephrine – sleep, mood, eating habits
a. Disorder associated with malfunctioning - depression
3. Serotonin – mood, sleep, impulsivity, aggression, appetite
a. Disorder associated with malfunctioning - depression
4. Dopamine – movement, reward, learning, attention
a. Disorder associated with malfunctioning - Parkinson’s disease & Schizophrenia
5. GABA – primary INHIBITORY neurotransmitter in brain; affects anxiety and movement
a. Disorder associated with malfunctioning – severe anxiety, epilepsy
6. Endorphin – modulation of pain (“Runner’s high”)
G. Nerve – a bundle of axons from many neurons
IV. The central nervous system (CNS)
A. Spinal cord – connects brain to PNS; spinal reflexes (simple unlearned response to a stimulus
to a stimulus that may require only two neurons, a sensory neuron & a motor neuron)

Fall 2015
Feldman - 5
B. Brain
1. Hindbrain
a. Brainstem – handles functions critical to physical survival
i. pons – relay station for motor messages b/t cerebellum & motor cortex
ii. reticular formation – arousal system involved in alertness & attention
iii. medulla – heartbeat, breathing, blood pressure, swallowing, coughing
b. Cerebellum – smooth and skilled movement; muscle tone & posture
2. Midbrain
a. Substantia nigra – unconscious motor actions
3. Forebrain
a. Thalamus – relay station b/t cerebral cortex and sensory information (for all senses
except smell)
b. Hypothalamus – hunger, thirst, body temperature, physiological aspects of emotion
c. Limbic system
i. amygdala – emotion (esp. response to unpleasant or punishing stimuli)
ii. hippocampus – memory consolidation (forming new memories), navigational
ability
d. Cerebrum – largest structure in human brain
i. Cerebral cortex
o Gray matter vs. White matter
o Cerebral hemispheres – lateralization of brain function
o Left hemisphere – controls right side of body
Language
Broca’s area (damage results in Broca’s aphasia – difficulty producing
speech; understanding fine)
Wernicke’s area (damage results in Wernicke’s aphasia – difficulty
understanding speech; production fine but doesn’t make sense)
Math & logic
Details
o Right hemisphere –