Ch. 2 Neuroscience Flashcards
Neuroplasticity
brains ability to change by reorganizing after damage or by building new pathways based on experience
Neuron
a nerve cell; basic building block of nervous system
Cell body
contains the nucleus
dendrites
neurons branching extensions that receive and integrate messages, conducting impulses toward the cell body
axon
segmented neuron extension that passes messages through its branches to other neurons or muscles/glands
glial cells
cells in nervous system that support, nourish, and protect neurons; also play a role in learning, thinking, and memory
action potential
neural impulse; brief electrical charge that travels down an axon
threshold
level of stimulation required to trigger a neural impulse
refractory period
brief resting pause that occurs after neuron has fired
all-or-none response
neurons reaction of either firing or not firing
synapse
junction between the axon tip of sending neuron
neurotransmitters
chemical messengers that cross the synaptic gap between neurons
reputake
neurotransmitter’s reabsorption by sending neuron
agonist
molecule that increases neurotransmitters action
antagonist
molecule that inhibits/blocks a neurotransmitters action
nervous system
consists of all three nerve cells of peripheral and central nervous system
CNS
brain and spinal cord
Peripheral Nervous System
sensory and motor neurons that connect the CNS to the rest of the body
nerves
bundled axons that form neural cables connecting the CNS with muscles, glands, and sensory organs
sensory neurons
neurons that carry incoming info from the body’s tissue and sensory receptors to the brain and spinal cord
motor neurons
neurons that carry outgoing info from the brain and spinal cord to muscles and glands
interneurons
neurons within the brain and spinal cord
Somatic nervous system
division of peripheral nervous system that controls the body’s skeletal muscles
sympathetic nervous system
division of autonomic nervous system that arouses the body, mobilizing its energy
parasympathetic nervous system
division of autonomic nervous system that calms the body, conserving energy
endocrine system
body’s slow chemical communication system
hormones
chemical messengers that are manufactured by endocrine glands, travel through the bloodstream and affect other tissues
adrenal glands
pair of endocrine glands that sits above kidneys and secretes hormones that help arouse the body in times of stress
pituitary gland
most influential gland, regulates growth and controls other endocrine glands
brainstem
oldest part and central core of the brain, responsible for automatic survival functions
medulla
base of brainstem, controls heartbeat and breathing
thalamus
brains sensory control center, directs messages to sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla
reticular formation
nerve network that travels through brainstem into the thalamus, filters info and plays a role in arousal
cerebellum
“little brain” at rear of brainstem, processes sensory input, coordinates movement, output and balance, enables nonverbal learning and memory
limbis system
neural system located below cerebral hemispheres, associated with emotions and drives
amygdala
two lima-bean-sized neural clusters in limbic system, linked to emotion
hypothalamus
neural structure in limbic system below the thalamus, directs several maintenance activities, helps govern the endocrine system via pituitary gland, linked to emotion and reward
frontal lobes
portion of cerebral cortex, involved in speaking and muscle movements and in making plans and judgments
parietal lobes
portion of cerebral cortex, receives sensory input for touch and body positions
occipital lobes
portion of cerebral cortex, includes areas that receive info from visual fields
temporal lobes
portion of cerebral cortex, includes auditory areas, each receiving info from opposite ear
motor cortex
portion of cerebral cortex, controls voluntary movement
somatosensory cortex
portion of cerebral cortex, registers and processes body touch and movement sensations
neurogenesis
formation of new neurons
corpus callosum
large band of neural fibers connecting two brain hemispheres and carrying messages between them
split brain
condition resulting from surgery that separates brain’s two hemispheres by cutting the fibers connecting them
