Motor System Flashcards
fasciculation
Quick twitch of all muscle fibers in a single motor unit
myoclonus
brief involuntary contraction of a muscle or group of muscles
tremors
involuntary rhythmic movements of a body part
fibrillations
random, spontaneous, brief contractions of single muscle fibers
Nerve conduction studies
determine if damage is at nerve, neuromuscular junction, or muscle
EMG
distinguishes between denervated muscle and myopathy
feedfoward
anticipatory use of sensory information
feedback
use of sensory info during and after
function of lateral corticospinal tract
-voluntary movement and fractionation
-distal muscles, including wriest and finger extensors, ankle and toe dorsiflexors, and hand and foot intrinsic muscles
rubrospinal tract function
-excite flexor motor neurons and inhibit extensor motor neurons
-wrist and finger flexors
medial corticospinal function
-motor neurons that provide voluntary control to neck, shoulder, and trunk muscles
-postural movements
reticulospinal tract function
-posture and gross limb movement
-muscle synergies
-neck reflexes to visual or auditory input
lateral vestibulospinal tract
-facilitates extensors and inhibits flexors; postural muscles
-proprioception
medial vestibulospinal tract
receives info on head movement and position from vestibular apparatus
ceruleospinal tract
releases norepinephrine resulting in facilitation of tonic spinal motor neurons
-activated by intense emotions
raphespinal tract function
-activated by intense emotions
-releases serotonin
-role in pain modulation
corticobulbar tract
synapses with CN 3,4,5,6,7,9,10,11,12
where is primary motor area
in precentral gyrus
where is the premotor area
lateral surface of hemisphere
where is the supplementary motor area
superior and medial surface of the hemisphere
where is Broca’s hemisphere
on inferior and lateral surface of hemisphere
