Biology and Behavior (ch 3 ) Flashcards
Dendrites
detect information from other neurons
cell body
information is collected and integrated
axon
information is conducted to the terminal buttons
terminal buttons
small nodules that release chemical signals from the neuron to the synapse
synapse
gap between the terminal buttons of a sending neuron where chemical communication occurs between neurons
action potential
electrical signal that passes along the axon and subsequently causes the release of chemicals from the terminal buttons
resting membrane potential
electric charge of a neuron when it is not active (~70 millivolts)
two ions: sodium and potassium
sodium potassium pump
increases potassium and decreases sodium inside the neuron, maintaining resting membrane potential
excitatory signal
depolarize cell membrane, increase the likelihood that a neuron will fire
inhibitory signals
hyperpolarize the cell, decrease the likelihood that the neuron will fire
when a neuron fires
sodium gates in the cell membrane open, allows sodium to rush into the neuron which positively charges it
potassium channels open to allow potassium ions inside the cell membrane to rush out
relative refractory period
brief period of time after action potential when a neurons membrane potential is more negative, making it harder to fire again
all or none principle
principle that when a neuron fires, it fires with the same potency each time
nodes of ranvier
small gaps of exposed axon between the segments of myelin sheath where action potentials take place
neurotransmitters
chemical substances that transmit signals one neuron to another, stored in vesicles
acytelcholine
motor control over muscles, learning, memory, sleeping, and dreaming
norepinephrine
arousal, vigilance, attention
serotonin
emotional states and impulsiveness
dopamine
reward and motivation
GABA
inhibition of action potentials, anxiety reduction
glutamate
enhancement of action potentials learning and memory
endorphins
pain reduction/ reward
agonists
drugs and toxins that enhance the actions of neurotransmitters
antagonists
inhibit actions of neurotransmitters
EEG
measures electrical activity in the brain
PET
injection of harmless radioactive substance, finds most active brain areas
MRI
powerful magnetic field to determine the location of brain damage or brain tumors
fMRI
imaging technique used to examine changes in the activity of the brain by measuring changes in oxygen levels
TMS
strong magnets to briefly interrupt normal brain activity to study brain regions
cerebral cortex
outer layer of brain tissue which forms the convoluted surface of the brain, site of all thoughts, perceptions, and complex behavior
gray matter
dominated by neurons cell bodies and non myelinated axons that communicate with nearby neurons
corpus callosum
massive bridge of millions of axons that connects the hemispheres of the brain
occipital lobes
region important for vision
parietal lobes
devoted partially to touch
temporal lobes
important for processing auditory information, memory, and object/face perception
frontal lobes
essential for planning and moement
prefrontal cortex
frontmost portion, important for attention, working memory, decision making, appropriate social behavior, and personality
split brain
removing the corpus callosum results in the two hemispheres not communicating
thalamus
receives the most sensory information, organizes it, relays to cortex
hypothalamus
main regulatory structure, functions many organs, regulates temperature, body rhythms, blood pressure, and glucose levels
hippocampus
formation of new memories
amygdala
biological stimuli, fight or flight, evaluates facial expressions emotional significance
basal ganglia
planning and producing movement, damage to this area can cause tremors or parkinson’s
cerebellum
for proper motor function and motor memory
endocrine system
communicates through hormones and influences thoughts, behaviors, and actions
sympathetic system
prepares body for action
parasympathetic division
returns the body to a resting state
