brain control of movement Flashcards
top-down motor control
The brain controls both voluntary and
involuntary movements
Axons from Motor Cortex (M1) descend along 2 major pathways, which are…
- Lateral
- Ventromedial
Lateral Pathways subsets
Corticospinal
-ipsilateral
(human-specific)
Rubrospinal tract
-contralateral
(older structure)
Corticospinal ipsilateral or counterlateral
ipsilateral
Rubrospinal tract ipsilateral or counterlateral
counterlateral
Vestibulospinal helps with
- eyes stable
- upright balance
tectospinal tract helps….
up.
colliculus orient
head, trunk,
shoulders
Humonculous:
distorted map of muscles of the contralateral side
Located at posterior end of Frontal lobe
what codes the direction of movement:
motor cortex
Donoghue & Sanes at Brown University
mapped motor nerves that controlled whisker
movements (purple), then lesioned some. The Motor map reorganized to later
controlling the forelimb (red) and eye movements (yellow)
why does phantom limb pain happen
needs
feedback of unclamped hand
Planning & Executing Complex Movements steps
Prefrontal (strategic) > Supplemental (tactical) > Premotor
(sequence) >
M1 (activation)
Weinrich and Wise found that …
some neurons in an area of macaque monkeys' area 6 cortex (SMA, PMA) fire when the monkeys planned to do things like reach for or bite a peanut.
Apraxia
inability to perform complex (but not simple) movements -
what results in apraxia
Lesions in Supplemental Motor Area
mirror neurons
Premotor and Supplementary Motor Areas fired similarly when they simply observed the (intention) of the same action
mirror neurons are sensitive to …
intention of movement
they will fire even when the end behavior is blocked: