N33 Flashcards
(29 cards)
3 principle elements of voluntary movement
location of target, movement program, execution
2 types of movement programs in pyramidal system
praxic and intentional
Praxic movement program
“how” of movements; cerebral cortical
Intentional movement program
“when” of movements; basal ganglia and cerebellum
Primary motor cortex location
precentral gyrus, brodmann’s area 4
Primary motor cortex path
Layer V neurons -> corticospinal tract -> vental horn
Primary motor cortex function
innervate distal musculature for high degree of control; over 1 joint; specific well-defined, simple fine distal movements
Primary motor cortex threshold
Low
Sensory input to Primary motor cortex
position of limb and speed of movement (from thalamus and SI)
Premotor Cortex (PMC) location
superior and middle frontal gyri, Brodmann’s area 6
Premotor Cortex (PMC) inputs
Mainly PMA, reciprocal connections with MI, SMA, and PMA
Premotor Cortex (PMC) outputs
reticular formation and ventral horn
Premotor Cortex (PMC) function
proximal and axial mm., complex planning and preparation for motor movement; integration of external stimuli into movements (visual); also coordinates movements of the limbs at more than 1 joint; large muscle groups
Supplementary Motor Area (SMA) location
medial and superolateral frontal lobes; medial area 6
Supplementary Motor Area (SMA) threshold
HIGH
Supplementary Motor Area function
coordinate movement of both sides of the body for posture; direct action of proximal muscles and indirect on distal via SMA->MI
SMA neurons excite
MI neurons to activate distal muscles
Presupplementary cortex
learning of new motor sequences, SMA retains learned sequences and selects motor programs
Posterior Parietal Motore Area (PMA) location
parietal lobe, areas 5,7
Posterior Parietal Motore Area area 5 function
Inputs from vestibular system (orientation), PMC (motor plans), and limbic system (motivation)
Posterior Parietal Motore Area area 7 function
visual and auditory inputs
Are 5 projects to
area 7 and PMC, and area 7 to PMC
Posterior Parietal Motore Area function
to integrate external stimuli, motivational state, and position to initiate movement
Frontal Eye Fields location
posterior middle frontal gyrus, area 8
