Module 1.3 Flashcards
The Neuron and Neural Firing
Neurons
neural cells that transmit information
Glial cells
cells that provide structures, insulation, communication, and waste transport
reflex arc
demonstrates how neurons within the central and peripheral nervous systems work together to respond to stimuli
sensory neurons
works in the spinal cord alongside motor and interneurons to carry incoming information from the body’s tissues and sensory receptors
motor neurons
works in the spinal cord alongside sensory and interneurons to carry outgoing information to the muscles and glands
interneurons
works alongside sensory and motor neurons to process sensory inputs and motor outputs
Neural transmission
most commonly occurs in an orderly, systematic way that involves the all-or-nothing principle, depolarization, refractory period, resting potential, reuptake, and threshold.
all-or-nothing principle
a neuron’s reaction of either firing (with a full-strength response) or not firing
Depolarization
the loss of the inside/outside charge difference causes the next of axon channels to open, and then the next, like falling dominos
refractory period
in neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state
resting potential
the positive-outside/negative-inside state
reuptake
a neurotransmitter’s reabsorption by the sending neuron
Threshold
the level of stimulation required to trigger a neural impulse
Neurotransmitter
chemical messengers that cross the synaptic gaps between neurons
Excitatory
making action potential more likely
Inhibitory
making an action potential less likely
Dopamine
neurotransmitter that influences movement, learning, attention, and emotion. too much linked to schizophrenia; too little linked to tremors and decreased mobility in Parkinson’s disease
Serotonin
neurotransmitter that affects mood, hunger, sleep, and arousal. too little is linked to depression
Norepinephrine
neurotransmitter that helps control alertness and arousal. undersupply can depress mood
Glutamate
a major excitatory neurotransmitter; involved in memory. too much can produce migraines or seizures
GABA
a major inhibitory neurotransmitter; undersupply linked to seizures, tremors, and insomnia
Endorphins
natural, opiate like neurotransmitters linked to pain control and pleasure
Substance p
a neuropeptide that acts as a neurotransmitter in the central and peripheral nervous systems.
Acetylcholine
neurotransmitter that enables muscle action, learning, and memory; the deterioration of ACh-producing neurons is connected to Alzheimer’s disease
