The Brain and the Nervous System Flashcards
dendrites
the little feelers that receive information
axon
carries output to other neurons
axon terminals
the end of the axon that actually puts the info into the synapse
synapse
the junction between two nerve cells, which is a minute gap through which information
excitatory synapses
make the postsynaptic neurons more likely to fire
inhibitory synapes
make the postsynaptic neurons less likely to fire
base line for neuron fire
-55mV
A neuron in resting state
is polarized
negative on the inside, positive on the outside (difference of -70mV)
Action Potential
the movement of the positive from the outside to the inside creates energy which allows the neuron to fire
White matter
myelinated, created for long distance communication, the highways of the brain.
grey matter
un-myelinated, short distance communication, the neighbors of the brain
the average human has _____ neurons in their brain
30-100 billion
the average human has _____ synapses in their brain
500 trillion
Acetylcholine
motor control over muscles
norepinephrine
arousal, fight or flight response, attention
serotonin
emotional states and impulsiveness, dreaming
dopamine
reward and motivation, motor control over voluntary movement
GABA
inhibition of action potentials, anxiety reduction
glutamate
enhancement of action potentials, learning and memory
endorphins
pain reduction, reward
transcranial magnetic stimulation
scientists can use TMS to study the effects of temporary brain damage, it disrupts brain activity by activating all neurons at once with a magnet
electroencephalography
shows the electrical activity of large populations of neurons with high temporal precisions
PET and fMRI
reveals which brain locations are particularly active at any moment in time by recording where blood flow is in the brain
spinal cord
coordination of reflexes; carries sensory information to the brain and motor signals away from the brain