Voluntary Movement Flashcards
voluntary actions
self-initiated
learned
improve with practice
purposeful
semi-automatic actions
voluntary but you don’t have to think about them
usually repetitive sequences e.g breathing, chewing, walking
can be modified at any point
central pattern generators
drive semi automatic actions
central sulcus
dip between the motor and sensory cortex
corticobulbar pathway
descending pathway responsible for innervating several cranial nerves e.g trigeminal, facial, hypoglossal
corticospinal pathway
descending pathway carrying motor info from brain to spina cord
pyramidal decussation
point in medulla where majority of axons in corticospinal pathway cross to the other side
what side are the majority of axons in the corticospinal pathway on
the crossed side i.e the lateral corticospinal tract
what side are the minority of axons in the corticospinal pathway on
the original side i.e the anterior corticospinal tract
what does damage to lower motor neurone result in
no reflexes and no voluntary movements as the final common pathway is affected
results in muscle atrophy (muscles waste away)
what does damage to the upper motor neurone result in
affects corticobulbar and corticospinal tracts therefore no voluntary movements
reflexes still present if at spinal level due to them being monosynaptic arches
what can cause damage to lower motor neurons
nerve injury , viral infections e.g polio
what can cause damage to upper motor neurons
CNS injury e.g a stroke
basal ganglia
collection of several interconnected sub cortical nuclei
influence output from motor cortex via feedback loops
what can damage to the basal ganglia result in
movement disorders e.g Parkinson’s, Huntington’s
