1. Neuron “Talk”
“What one neuron tells another neuron is simply how much it is excited.” (Francis Crik, 1994)
“All information processing in the brain involves neurons ‘talking to’ each other at synapses” (Snyder, 1984)

2. Neural Communication Biological Psychology
branch of psychology concerned with the links between biology and behavior
some biological psychologists call themselves behavioral neuroscientists, neuropsychologists, behavior geneticists, physiological psychologists, or biopsychologists
Neuron
a nerve cell
the basic building block of the nervous system

3. Neural Communication Action Potential / Impulse
a neural impulse; a brief electrical charge that travels down an axon
generated by the movement of positively charged atoms in and out of channels in the axon’s membrane
Threshold
the level of stimulation required to trigger a neural impulse (to get it excited).
Excitation – the process of making the neuron receiving NT more likely to generate an action potential.
Inhibition - the process of making the neuron receiving NT less likely to generate an action potential.

4. Neural Communication Dendrite Axon Myelin [MY-uh-lin] Sheath
the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body
Axon
the extension of a neuron, ending in branching terminal fibers, through which messages are sent to other neurons or to muscles or glands
Myelin [MY-uh-lin] Sheath
a layer of fatty cells segmentally encasing the fibers of many neurons
enables vastly greater transmission speed of neutral impulses

5. Neural Communication

6. Tips to Remember
Ions have a charge either (+) or (-), when they move it makes ELECTRICITY = Action Potential
All matter has a natural tendency to move from a crowded to a less crowed situation. (-) ions trapped inside!
A neuron’s membrane is normally impermeable, but NT weaken it , allowing the “pump” to begin.

7. Neural Communication/Transmission
depolarization – change in the cell’s membrane potential.
all-or-none principle - the cell either fires completely or not at all; it doesn’t fire a little or a lot.
direction of impulse - the cells only fire one way, the impulse can’t come the other direction.
refractory period - after a cell fires, it won’t fire again for a certain period of time.
resting potential (or polarization)- the cell is “waiting” to fire.
The overall negative charge inside the neuron waiting for depolarization the flood of positive ions (Na) to enter.

8. Neural Transmission With a neighbor/partner…
Discuss how neural transmission is like flushing a toilet.
Include these elements in your discussion:
Depolarization
Polarization
All-or-none principle
Direction of impulse
Refractory period
Threshold
Resting potential
Action potential

9. Toilet & Neural Transmission
depolarization - represented by the toilet flushing
all-or-none principle - the toilet either flushes completely or not at all; it doesn’t flush a little or a lot
direction of impulse - the toilet only flushes one way, the impulse can’t come the other direction (you hope!)
refractory period - after you flush the toilet, it won’t flush again for a certain period of time, even if you push the handle repeatedly
threshold - you can push the handle a little bit, but it won’t flush until you push the   handle past a certain critical point - this corresponds to the level of excitatory neurotransmitters that a neuron must absorb before it will fire
resting potential- if you are using a toilet with a tank, the water in the tank can represent resting potential. The toilet is “waiting” to fire, and the water in the tank represents the overall negative charge inside the neuron waiting for depolarization
action potential - the action potential is represented by opening the flap in the tank and the water

10. Neural Communication Synapse Neurotransmitters
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, neuro-transmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether it will generate a neural impulse

11. Neural Communication
Dopamine Pathways
Serotonin Pathways