ch3 vocab* Flashcards
Dendrites
neuron’s branching extensions that receive and integrate messages
Myelin sheath
enables greater transmission speed as neural impulses hop from one node to the next
Axon
neuron extension that passes message through its branches to other neurons
Action potential
a brief electrical charge that travels down an axon
Refractory period
a brief resting pause that occurs after a neuron has fired
Reuptake
travel across the synapse and bind to receptor sites on the receiving neuron
Agonist
molecule that increases a neurotransmitter’s action
All-or-none response
neuron’s reaction of either firing (with a full-strength response) or not firing
Interneuron
neurons within the brain and spinal cord that communicate internally
Endorphins
natural, opiate-like neurotransmitters linked to pain control and to pleasure
Acetylcholine
best-understood neurotransmitters has role in learning and memory
Neurotransmitter
chemical messengers that cross the synaptic gaps sending neurons
Threshold
level of stimulation required to trigger a neural impulse
Antagonist
a substance that interferes with or inhibits the physiological action of another
Soma
cell body
Synapse
junction between the axon tip of the sending neuron and the dendrite
Axon terminals
where action potential comes to a screeching halt
Central nervous system
brain and spinal cord
Sympathetic nervous system
division of the autonomic nervous system that arouses the body
Hormones
chemical messengers that travel through the bloodstream, and affect other tissues
pituitary gland
regulates growth and controls other endocrine glands
Sensory (afferent) neurons
carry information from the body’s tissues and sensory receptors to brain and spinal cord
autonomic nervous system
peripheral nervous system part controls the glands and the muscles of internal organs
Adrenal glands
secrete hormones that help arouse the body in times of stress
Motor (efferent) neurons
carry outgoing information from the brain and spinal cord to the muscles and glands
Endocrine system
set of glands that secrete hormones into the bloodstream
Nerves
bundles axons that form neural “cables” connecting the central nervous system with muscles, glands, and sense organs
EEG (Electroencephalogram)
amplified recording of the waves of electrical activity across the brain’s surface
PET scan
detects where a radioactive form of glucose goes while the brain does a given task
Hypothalamus
helps govern the endocrine system via pituitary gland, linked to emotion and award
Cerebellum
the “little brain” at the rear of the brainstem,muscle movement, balance
Hippocampus
helps process for storage explicit (conscious) memories of facts and events
limbic system
neural system (including the amygdala, hypothalamus, and hippocampus)
Lesion
naturally or experimentally caused destruction of brain tissue
Brainstem
responsible for automatic survival functions
fMRI
a technique for reveal blood flow and brain activity
Medulla
base of the brainstem; controls heartbeat and breathing
Amygdala
two lima bean-sized neural clusters in the limbic system, linked to emotion
Pons
sleep and arousal
Frontal lobes
portion of the cerebral cortex involved in making plans and judgments
CAT scan
series of X-ray photographs taken from different angles and combined by computer
Plasticity
brain’s ability to change, especially during childhood
occipital lobes
includes areas that receive information from the visual fields
Parietal lobes
receives sensory input for touch and body position
Cerebral cortex
brain’s outer surface of interconnected neural cells
Glial cells
cells in the nervous system that support, nourish, and protect neurons
Motor cortex
area at the rear of the frontal lobes that control voluntary movements
Association areas
involves high mental functions like learning, thinking, and speaking
Sensory cortex
area at the front of the parietal lobes registers and processes body touch and movement sensations
Aphasia
impairment of language
