unit 2a: biological bases of behavior Flashcards
neurons
basic building blocks of the nervous system. send & receive messages from other structures in the body. individual nerve cells
soma (cell body)
component of a neuron. produces energy that fuels the activity of the cell
dendrites
component of a neuron. receives impulses from axon terminals of other neurons and conduct them toward the cell body
axon
component of a neuron. transmits impulses away from the cell body to the synapse
myelin sheath
component of a neuron. insulates and protects axon. speeds up impulses. can cause multiple sclerosis
nodes of ranvier
component of a neuron. regularly spaced gaps in the myelin sheath to transmit faster
axon terminals
component of a neuron. at the end of a neuron and secrete neurotransmitters
action potential
a brief electrical charge that travels down the axon of a neuron
selectively permeable
allows some particles to pass in & out while blocking other
all-or-none law/principle
principle stating that either a neuron is sufficiently stimulated and an action potential occurs, or a neuron is not sufficiently stimulated and the action potential doesn’t occur. always fires with the same strength and intensity
refractory period
short period between action potentials
neurotransmitters
chemical messages released from the axon terminals
synapse
the tiny gap between the axon terminal of the sending neuron and the dendrites of the receiving neuron
reuptake
a neurotransmitter’s reabsorption by the sending neutron
agonists
drugs that boost the effect of a neurotransmitter
antagonist
drugs that block the effect of a neurotransmitter
what comprises the nervous system?
the central nervous system and the peripheral nervous system
what are the parts of the central nervous system?
the brain and spinal cord
spinal cord
two-way information highway connecting the brain and peripheral nervous system
what do sensory neurons do?
they carry information from the receptors to the spinal cord and the brain
what do motor neurons do?
carry information away from the brain and spinal cord to the muscles and glands so they can take action
what do interneurons do?
process information and connect other neurons within the central nervous system
peripheral nervous system
nerve cells that send messages between the central nervous system and all parts of the body
what comprises the peripheral nervous system?
the somatic and autonomic nervous systems
somatic nervous system
controls voluntary activities, serves arousal functions
autonomic nervous system
controls involuntary activities, regulates the body’s vital functions (breathing, digestion, blood pressure), and involves emotions. contains the sympathetic and parasympathetic nervous systems
sympathetic nervous system
part of the autonomic nervous system. prepares the body for fight-or-flight responses
parasympathetic nervous system
part of the autonomic nervous system. calms the body after emergencies and restores the body’s energy
the endocrine system
a system of glands that secrete hormones. messages are sent chemically throughout the body
what does the adrenal gland do?
secretes steroids that increase resistance to stress and promote muscle development
what does the pituitary gland do?
it is a “master gland” that secretes a wide range of hormones. mostly related to growth
what does the thyroid gland do?
secretes hormones involved with metabolism
lesion
a naturally or experimentally caused destruction of brain tissue
clinical observation
oldest method of studying the brain
cat scan
produces a 3-d view of the brain
mri scan
3-d view that shows more clear details of the brain (blood vessels, nerves, bones & organs)
pet scan
visual display of brain activity that detects where a radioactive form of glucose goes
fmri scan
reveals the brain’s functioning as well as its structure. lights up when mental functions are activated
eeg scan
records the electrical activity of the brain creating “brain waves”
brainstem
responsible for automatic survival functions. comprised of the medulla and pons
medulla
in the brainstem. controls basic life support functions (heartbeat, breathing)
pons
in the brainstem. controls equilibrium to coordinate voluntary movements
reticular formation
involved in arousal and alertness
thalamus
the brain’s sensory switchboard. directs messages for all senses except for smell
cerebellum
helps coordinate voluntary movement and balance
the limbic system
important role in regulating emotion and memory. comprised of the amygdala, hypothalamus, and the hippocampus
amygdala
part of the limbic system. controls emotional responses, such as fear, anger, and aggresion
amygdala
part of the limbic system. controls emotional responses, such as fear, anger, and aggression
hypothalamus
part of the limbic system. helps regulate many of the body’s maintenance activities (eating, drinking, body temperature)
hippocampus
part of the limbic system. processes new memories for permanent storage
cerebrum
the most complex part of our brain. is divided into 2 hemispheres
cerebral cortex
makes up the body’s ultimate control & information processing center (learning, remembering, and thinking)
glial cells
cells in the nervous system that support, nourish, and protect neurons
frontal lobe
front-most lobe. responsible for judgment and decision-making
parietal lobe
top-most lobe. responsible for touch, pain, and temperature
temporal lobe
bottom-most lobe. responsible for hearing and memory
occipital lobe
back-most lobe. responsible for vision
motor cortex
initiates voluntary movements
sensory cortex
registers and processes body sensations
association areas
found in all 4 lobes, involved in higher mental functions
aphasia
loss or impairment of the ability to understand language or express oneself through language
broca’s area
damage in this area results in difficulty with producing speech. can form ideas but cannot express them
wernicke’s area
damage in this area can result in inability to understand language
plasticity
the brain’s capacity for modification
corpus callosum
axon fibers that connect the two brain hemispheres
