Unit 1- 1.3 Flashcards
basic building block of nervous system
neuron
cell’s life support center
cell body
receives messages from other cells
dendrites
passes messages away from the cell’s body to other neurons,muscles, and glands
axon
covers axon of neurons and helps speed neural impulses
myelin sheath
a neural impulse (a brief electrical charge that travels down the axon)
action potential
supports the billions of neurons in the brain
glial cells
level of stimulation required to trigger a neural impulse
threshold
another action potential can’t be easily produced
refractory period
the neural either fires completely or it does not
all-or-none response
chemical messengers that cross the synaptic gaps between neurons
neurotransmitters
the junction between the axon terminal of sending neurons and dendrites or cell body of the receiving neuron
synapse
when unused neurotransmitters are reabsorbed by sending the neuron in a process
reuptake
influence the perception of pain or pleasure
endorphins
molecules that increase a neurotransmitter’s actions
agonist
molecules that decrease a neurotransmitter’s actions
antagonist
system of glands and hormones in the body that sends messages to the body through the bloodstream
endocrine system
chemical messengers made by the endocrine system
hormones
non-subscription drugs and sometimes develops self-harming abuse disorders
psychoactive drug
continued substance craving and uses despite physical risk
substance use disorder
drugs that reduce neural activity and slow bodily functions
depressants
when the use of drugs cause a user’s brain chemistry to adapt to offset the drugs effects
tolerance
craving of drugs or certain behaviors
addiction
discomfort or distress when stopping using an addictive drug
withdrawal
a drug that depresses the central nervous system (CNS)
barbiturates
a pain killer drug that signals to the spinal cord, and produces euphoria
opioids
drugs that excite neural activity and speeds up bodily functions
stimulants
drugs that distort perceptions and evoke sensory images
hallucinogens
experiences when someone is almost dead but lives
near-death experience
