advance neuro lec 12

brain

influ motor activity of sc

initiate voluntary movements

hierarchy of control

highest lvl- strategy - association areas of neocortex and basal ganglia

middle- tactics- motor cortex cerebellum

lowest lvl- execution- brianstem, sc

sensorimotor sys

sensory info used by all lvls of motor sys

umn cell bodies

cereberal cortex or brainstem

umn axons

descending motor pthways that move down into brainstem and potentially into sc via diff paths

umn

supply input to lmn

cortex

voluntary movements

intended skilled complex movements

brainstem

reg core muscle tone orients eyes, head, body w other sensory info

posture orientation navigation

betz cells

big pyramidal neuron cell in layer v

umn

motor cortex

come send axons down sc and synapse right onto lmn

some branch and send collaterlas to inhib interneurons

some send to brainstem and or sc

receive input form other cortical areas and form thalamus (also form cerebellem and bg

lateral descending pathways

lateral coticospinal, rubrospinal, corticobulbar,

voluntary movement of distal muscaluture under cortical control

ventromedial descending thway

ventral corticospinal vestibulospinal tectospinal reticulusponal

control of posture and locomotion under brainstem control

lateral corticospinal tract

lateral/ distal prt of body

ventral corticospinal tract

trunk proximal muscles

corticobulbar tract

face

corticonuclear

ready 

posteriro parietal and preforntal ares

set

premotor cortex

go

m1 and some pma

umn syndrome/ lesion cause

damage to motor system aboce lvl of amn

ex stroke tbi, ms

umn symptoms

weakness/paralysis

atrophy in uncommon

fasciculations and fibrilations are absent

hypertonia

hyperreflexia

spasticity

clonus

babinski sign

apraxia

motor disorder casued by damage to brain can be congenital

musculoskeletal movments aren’t impaired

ability to plan complex movmenets sequences of movements and/or perform movements using objects is impaired