exam two (ch.14) Flashcards
highest level of motor control involves association areas and basal ganglia which functions to
devise strategy
the middle level of motor control involves the primary motor cortex and cerebellum which funtion to
fine tuning strategy
execution of the motor strategy which is controlled by what structures
brain stem and spinal cord
_____ system influences all levels of the motor system
somatosensory
lateral pathways have cortical control and they do what movements
voluntary movements of distal limbs
ventromedial pathways of the brain stem control
postural muscles
the rubrospinal tract originates in ___ ___ (midbrain)
red nucleus
what motor pathways controls posture and locomotion in the brain
vestibulospinal and tectospinal and pontine reticulospinal and medullary recticulospinal
motor pathway that is ventromedila and does head balance and head turning
vestibulospinal
motor pathway that is ventromedial and does orienting response
tectospinal
the ventriomedial pathways originate where
brain stem
ventromedial pathway that enhances antigravity
reflexes of the spinal
cord (maintain
standing)
pontine reticulospinal
ventromedial pathway that liberates antigravity
muscles from reflex
(opposite of the other
tract)
medullary reticulospinal
area 4 in the motor cortex is commonly called
primary motor cortex or M1
area 6 in the motor cortex is commonly called
higher motor area
the lateral region of the higher motor area is the ___ ____; the medial region is _____
premotor area and supplementary motor area
Microstimulation of prescribed
area of M1 normally elicits
whisker movement; Cut nerve that supplies whisker
muscles; Microstimulation now causes forelimb movement, this is an example of?
neuroplasticity (rewiring M1)
area 5 and 7 are involved in _____ somatosensory processing
complex
posterior pariteal (Area 5 and 7) dysfunction characterized by inability to identify objects by feeling them
even though sense of touch appears otherwise normal
astereoagnosia
results from posterior parietal lesion;
part of the body or world is completely ignored
neglect syndrome
consolidates inputs
from somatosensory areas 1, 2 and 3
area 5
Inputs from higher-
order visual cortical areas such as MT
area 7
Abstract thought, decision making and anticipating consequences of action
prefrontal cortex
area where signals turned into commands specifying how actions will be performed
area 6
area 6 (pre motor) also contains _____ neurons
mirror
outputs to the alpha motor neurons from M1 come from pyramidal cells in layer
V
Activity of M1 neurons encode _____ and _____ of movement
force and direction
Activity of each cell:
Represents a single “vote” and the direction of movement is dictated by a ____ ____ in M1
population vector
what brain structure does selection and initiation of “motivated” movements
basal ganglia
the basal ganglia recieves input from all aread of the neocortex and limbic cortex including ___ ____ and the ___ ____ from substantia nigra
motor cortex and dopaminergic system
B.G motor loop has an excitatory connection from ____ to ____
cortex to putamen
cortical activation to basal ganglia ___ putamen which inhibits ___ ____
excites; globus pallidus
excitation of globus pallidus results in
release of VLo (thalamus) from inhibition (off switch turned on)
VLo activity in turn stimulates activity in ____
SMA (supplementary motor area)
what disease is characterized by trouble initiating willed movements due to increased inhibition of the thalamus of basal ganglia
parkinsons
L-dopa works to facilitate production of dopmaine to increase ____ activity
SMA
Uncontrolled movements due to decreased inhibition of the thalamus by basal ganglia; Loss of neurons in caudate, putamen, globus pallidus (also
cortex
huntingtons
the vermis of the cerebellum contributes to ____ pathways; axial musculature
ventromedial
the cerebellar hemispheres contribute to ____ pathways; limb movements
lateral
the motor loop through the lateral cerebellum allows for proper execution of ___ ____ multi joint movements
planned, volunatry
Axons from layer V
pyramidal cells in the
sensorimotor cortex
(Areas 4, 6, and sensory
cortex) form massive
projections to pons which
then projects to the
cerebellum
pontine nuclei
cerebellum projects through the thalamus to the
motor cortex
there is an ___ connection from cortex to putamen
excitatory
exciting the putamen inhibits the ___ ____
globus pallidus
when the globus pallidus is inhibited there is the release of _____ from inhibition
VLo (thalamus)
when VLo is switched on what happens
activity will begin in SMA; which focuses behavior
there is also an _____ pathway that antagonizes diect pathway of motor function (they work together to select appropriate movements)m
indirect
