L39 Corticospinal and Corticobulbar Fibers Flashcards
what cortex does motor planning?
prefrontal and limbic cortex
what cortex does production of motor programs?
premotor cortex (BA 6)
what cortex executes motor activity?
primary motor cortex (BA 4)
what do the premotor cortex pyramidal layer 5 cells that project via? what does it do?
corticospinal tract
excite motor neurons
what does the medial aspect of the premotor cortex contain?
the supplemental motor area
what do the layer 5 pyramidal cells of the primary motor cortex make excitatory synapses to?
LMN’s in the spinal cord both directly and indirectly via interneurons
what has a distinct somatotropic map?
primary motor cortex
where does the motor cortex receive input from?
- primary somatosensory (BA 3,1,2)
- post. parietal areas (BA 5,7) = integrates sensory info for motor planning
- basal ganglia (via thalamus and premotor area)
- cerebellum (via thalamus)
- visual center
- auditory center
- limbic and prefrontal areas
where does the premotor cortex receive input from?
- post. parietal area
- basal ganglia (via thalamus)
- cerebellum (via thalamus)
what does simple finger movement activate?
- motor cortex
- somatosensory
what does complex finger movements activate?
- premotor cortex
- supplemental motor cortex
what does rehearsed finger movements activate?
-supplemental cortex (programmed from rehearsal)
what is the predominant role of the lateral corticospinal tract?
voluntary contraction of distal flexor muscles of the limbs - reaching and walking
sensory input from the lateral corticospinal tract is constantly processed by the ____ and modified by the ___ and ____
cortex
BG
cerebellum
where does the corticospinal tract start?
pyramidal cells layer 5 of preCG
