Psych Final - Brain Flashcards
neuron
a nerve cell; the basic building block of the nervous system
dendrite
the neuron’s bushy, branching extensions that receive messages and conduct impulses toward the cell body
axon
the neuron’s extension that passes messages through its branching terminal fibers that form junctions with other neurons, muscles, or glands
myelin sheath
covers axon of some neurons, helps speed neural impulses
action potential
a neural impulse; a brief electrical charge that travels down an axon
excitatory
positive (action) signals
inhibitory
negative (stop action) signals
threshold
the level of stimulation required to trigger a neural impulse
synapse
the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron
neurotransmitters
chemical messengers that cross 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 that neuron will generate a neural impulse
reuptake
when sending neuron reabsorbs excess neurotransmitters
axon terminal
end of neuron, forms junctions with other cells
receptors
where neurotransmitters bind to on the receiving neuron
synaptic gap
The tiny gap at the synapse; separation space between neurons
nervous system
the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems
nerves
bundled axons that form neural “cables” connecting the central nervous system with muscles, glands, and sense organs
sensory neurons
neurons that carry incoming information from the sensory receptors to the brain and spinal cord
motor neurons
neurons that carry outgoing information from the brain and spinal cord to the muscles and glands
interneurons
neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs
neural network
a group of synapses formed through repetition
sympathetic nervous system
the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations
parasympathetic nervous system
the division of the autonomic nervous system that calms the body, conserving its energy
