Unit 2: Biological Bases of Behavior Flashcards
glial cells
“glue cells”
supply nutrients and oxygen to neurons, insulate one neuron form another, destroy pathogens and remove dead neurons
neurons
nerve cells, basic building blocks of the nervous system
sensory neurons
carry incoming info from sense receptors to CNS
interneurons
carry info within the CNS, b/w sensory and motor neurons
motor neurons
carry outgoing info from CNS to muscles/glands
soma
neuron cell body
dendrite
bushy, branching extensions, receive messages and conduct impulses toward cell body
axon
extension of neuron through which messages are sent
threshold
level of stimulation required to trigger neural impulse
All or none responses
neurons either fire or don’t
action potential
neural impulse; a brief electrical charge that travels down the axon(one way only)
refractory period
when the positive ions are pumped out; and the axon is not able to receive another message
myelin sheath
layer of fatty cells, segmentally encasing the axons of many, not all neurons
makes transmission speeds faster
neurotransmitters
chemical messengers that fill the gap b/w dendrites and axons
reuptake
process by which excess neurotransmitters are reabsorbed by the sending neuron
Acetylcholine (ACh)
neurotransmitter that enables muscle action, learning and memory
malfunctions include Alzheimer’s
Dopamine
neurotransmitter that influences movement, learning attention, and emotion
oversupply linked to schizophrenia
undersupply is linked to tremors and decreased mobility in Parkinson’s
serotonin
neurotransmitter that affects mood, hunger, sleep and arousal
undersupply linked to depression
(some anti-depressants used to raise serotonin levels)
norepinephrine
neurotransmitter that helps control alertness and arousal
undersupply can depress mood
GABA (gamma-aminobutyric acid)
major inhibitory neurotransmitter (prevents neuron from firing)
undersupply linked to seizures, tremors and insomnia
glutamate
major excitatory neurotransmitter (excites neuron to fire); involved with memory
oversupply can overstimulate the brain, producing migraines/seizures (which is why some people avoid MSG)
endorphins
neurotransmitter that influences the perception of pain/pleasure
oversupply with opiate drugs can suppress the body’s endorphin supply
agonist
drugs that increase a neurotransmitter’s action
(ex: Opiates amplifies the sensation of pleasure that comes w endorphins)
antagonist
drugs that block neurotransmitter’s actions
(ex: curare is a type of poison that blocks ACh and produces paralysis)
lesion studies
studies that analyze brain structure
destroy parts of the brain and observe the consequences
electroencephalograms (EEGs)
studies that analyze brain structure
measures electrical activity on the brain surface
computed axial tomography (CAT)
studies that analyze brain structure; x-rays
magnetic resonance imaging (MRI)
studies that analyze brain structure; uses magnetic fields and radio waves
MEG
shows function
magnetic fields from the brain’s natural electrical activity
Positron emission tomograph (PET)
shows function
examine the brain’s consumption of radioactive glucose
fMRI
shows function
measures chance in blood flow related to energy use in brain cells
frontal lobe
responsible for speech, planning and muscle movement;
matures late in life
temporal lobe
receives auditory information, primarily from opposite ear
parietal lobe
receives sensory input from touch and body position
occipital lobe
responsible for sight, opposite visual fields
cerebral cortex
thin layer above the cerebrum
responsible for information processing
motor cortex
responsible for voluntary movement
sensory cortex
responsible for sensation of movement/touch
association areas
areas of the cerebral cortex not involved in primary motor or sensory functions and instead higher mental functions (learning, remembering, thinking, speaking)
cognitive neuroscience
brain activity linked with cognition
dual processing
information process occurs on both conscious and unconscious tracking
blindsight
condition in which a person can respond to a visual stimulus without consciously experiencing it
sleep
a periodic, natural, reversible and near total loss of consciousness
NREM 1
brief, near waking sleep
hallucinations/hypnagogic sensations such as falling or floating occur
wave type is alpha(awake but relaxed)
NREM 2
takes up half of sleep time
asleep but easily awakened
features sleep spindles, or bursts of rapid, rhythmic brain-wave activity
NREM 3
deep sleep featuring delta waves(large, slow)
REM
paradoxical sleep in which muscles relax but all other body systems are active
vivid dreams occur here
insomnia
sleep disorder characterized by an inability to fall asleep
narcolepsy
sleep disorder characterized by uncontrollable sleepiness/lapsing in REM sleep
sleep apnea
sleep disorder characterized by the inability to breathe while sleeping
night terrors
sleep disorder characterized by high arousal and the appearance of being terrified
most common in children below 7 yrs old
narcotics
depressants/barbiturates/opiates
dampen neural activity and slow body function
barbiturates
depress CNS, reduce anxiety but impair memory/judgement
opiates
ex: morphine, heroin
depress neural activity, temporarily lessening pain and anxiety
spinal cord
pathway for neural fibers traveling to and from the brain
controls simple reflexes
gate control theory of pain
brainstem
oldest part of the brain
responsible for automatic survival functions
thalamus
sensory control center which directs messages from sensory reception areas of the cortex and transmits replies to the cerebellum and medulla
cerebellum
processes sensory input, coordinates movement output and balance, enables nonverbal learning/memory
what are the four oldest brain structures?
spinal cord, brainstem, thalamus, cerebellum
what four structures make up the limbic system?
amygdala, hippocampus, hypothalamus, pituitary
amygdala
linked to emotion, particularly fear and anger
hippocampus
process explicit memories of facts and events for storage
hypothalamus
directs maintenance activities such as eating drinking and body temperature
pituitary
major endocrine system gland, regulates growth and controls other glands
what structures make up the cerebrum?
frontal, parietal, occipital, temporal lobes, motor, sensory cortex
cortisol
hormone released when under stress
Wernicke’s area
responsible for understanding word/language comprehension
Broca’s area
responsible for speaking/language production
