neurotransmitters

how did knowledge of how neurons communicate change over time?

first—through neurons fused w/ each other to communicate. delay in natural impulse travel led to belief in a break between neurons (synapse)

how wide is a synapse?

less than a millionth of an inch

list the 3 things that happen to excess neurotransmitter after an impulse crosses the synapse

• the excess neurotransmitters drift away

• broken down by enzymes

• or reabsorbed by the sending neuron (reuptake)

does a neurotransmitter affect the whole brain or just specific parts? explain & give two examples

particular neural pathways use 1 or 2 neurotransmitters which in turn affect particular emotions or behaviours

• ex: dopamine pathway, serotonin pathway

acetylcholine function

enables muscle action, learning, & memory

dopamine function

influences movement, learning, attention, & emotion

serotonin function

affects mood, hunger, sleep, & arousal

norepinephrine function

helps control alertness & arousal

glutamine function

a major excitatory neurotransmitter; involved in memory

what is the body’s reaction to exogenous drugs? what implications do you think this has for medication for disorders?

the brain stops producing its own endogenous neurotransmitters in response to the introduction of exogenous drugs

• this affects a person’s ability to discontinue medication therapy

define antagonist

a molecule that inhibits or blocks a neurotransmitter’s action

define agonist

a molecule that increases a neurotransmitter’s action

examples of antagonists?

botulin

example of agonists?

opiates