Ch8-Control of Movement Flashcards
controls digestive system & other organs [involuntary]
smooth muscles
controls movement in relation to environment [striped in appearance]
skeletal [striated] muscles
controls the heart; has properties of both skeletal & smooth muscles
cardiac muscles
synapse between motor neuron axon & muscle fiber
neuromuscular junction
alternating contractions of opposing muscle sets [flexor & extensor muscles]
antagonistic muscles
which neurotransmitter excites muscles to contract
acetylcholine
autoimmune disease that attacks acetylcholine at neuromuscular junction; inhibits movement
myasthenia gravis
fast contractions but fatigue rapidly [ex) sprinting]
fast-twitch fibers
less vigorous contractions without fatigue [ex) lip muscles]
slow-twitch fibers
uses oxygen; does not fatigue, slow-twitch
aerobic
does not use oxygen at the time; fatigues & needs oxygen to recover, fast-twitch
anaerobic
receptor that detects position or movement of a part of the body; allow for smooth movements
proprioceptor
detect stretch & tension of muscle & send messages to spinal cord to contract it [ex) knee jerk reflex]
stretch reflex
receptor parallel to the muscle that responds to a stretch; causes contraction of muscle
muscle spindle
respond to increases in muscle tension [located in tendons at opposite ends of muscle; brake on muscle to prevent too vigorous of a contraction]
golgi tendon organs
consistent auto responses to stimuli; involuntary[insensitive to reinforcements, punishments, & motivations], consistent, & automatic
reflexes
once initiated cannot be altered or corrected [stretch reflex, pupil dilation]
ballistic movement
many behaviors consist of rapid sequences such as……
speaking, dancing, playing, musical instrument
neural mechanisms in spinal cord that generate rhythmic patterns of motor output [ex) birds wing flapping, dog shaking to get dry]
central pattern generators
fixed sequence of movements; once begun sequence is fixed from beginning to end [ex) mouse grooming]; automatic, thinking about it interferes with action
motor program
built-in motor program in humans
yawning
what are the 3 infant reflexes?
grasp reflex [grab if object placed in hand]
Babinski reflex [fan toes if foot tickled]
rooting reflex [tickle cheek, will suck finger]
importance of understanding how the brain controls movement
enabling individuals who are paralyzed to be able to move
pioneering work of Fritsch & Hitzig - direct stimulation of the ___ _____ ____ elicits movements [frontal lobe, precentral gyrus]
primary motor cortex
motor cortex sends messages through axons to ________ & ______, then is sent to muscles
brain stem, spinal cord
cerebral cortex is particularly important for _____ ____ [ex) talking, writing]
complex actions
specific areas of motor cortex control _______ [contralateral]
specific areas of the body
when people “intend” a movement _____ is active
primary motor cortex
keeps track of the position of the body relative to the world [damage causes difficulty coordinating visual stimuli with movement]
posterior parietal cortex
stores sensory info relevant to a movement & also plans movements according to their probable outcomes
prefrontal cortex
damage to the _______ causes disorganized, irrational behavior [ex) jump in shower with clothes on]
prefrontal cortex
most active immediately before a movement; receives info about a target and the body’s current position
premotor cortex
along with prefrontal cortex, important for planning & organizing a rapid sequence of movements in a particular order; important for inhibiting habitual movement in order to do something else
supplementary motor cortex
active both during preparation for a movement & while watching someone else perform the same or similar movement [unknown whether they are the cause or result from social behavior]
mirror neurons
brain decides to act before you are conscious of it [voluntary & conscious are not synonymous]
readiness potential
paths from cerebral cortex to the spinal cord
corticospinal tracts
set of axons from the primary motor cortex, surrounding areas, & red nucleus [control periphery of body (hands & feet)]
lateral corticospinal tract
includes axons from many parts of cerebral cortex [controls neck, shoulders, trunk]
medial corticospinal tract
cerebellum is important for __ & ___
[contains 70% of nervous system neurons]
balance, coordination
cerebellar damage
difficulty calibrating eye movement, shifting attention, playing sports [examples: clapping hands, speaking, writing]
quick way to test cerebellum for damage or alcohol effects
finger-to-nose test
Ito-proposed that a key role of the _____ is to establish new motor programs that enable one to execute a sequence of actions as a whole
cerebellum
information eventually reaches the _____
cerebellar cortex
neurons in cerebellar cortex
purkinje cells-flat cells in sequential planes
parallel fibers-axons parallel to one another & perpendicular to planes of purkinje cells
the greater the number of excited purkinje cells, the greater their _________; controls timing of movement
collective duration of response
group of large subcortical structures in the forebrain; responsible for initiating action not guided by a stimulus
basal ganglia
3 parts of basal ganglia
caudate nucleus, putamen, globus pallidus
input come to ___ & ____ from cerebral cortex, then sends output to ____, then to the thalamus
caudate nucleus, putamen
globus pallidus
the ___ ___ select a movement by ceasing to inhibit it–circuit is particularly important for self-initiated behaviors
basal ganglia
ALS [amyotrophic lateral sclerosis] is due primarily to ______
the death of spinal motor neurons
Huntington’s Disease is associated with gradual, extensive brain damage, especially in which area?
caudate nucleus, putamen, & globus pallidus [basal ganglia]
