Voluntary Movement Flashcards
Describe semi-automatic Actions
voluntary but you don’t have to think about them.
often repeated movement sequences
adaptable
walking, breathing, chewing
What may semi-automatic actions be driven by?
central pattern generators
basic structure of a neuron?
cell body, dendrites, axon, axon terminal,
what allows the output of a CPG to be monitored at all times
effector organ reflex feedback
what are the three feedback loops associated with CPG and effector organs?
sensory feedback, reflex feedback, central feedback
describe voluntary actions
self- initiated, can be learned, better with time
describe the nerves in descending corticobulbar pathway?
motor controlled- voluntary
innervation of cranial nerve nuclei (bilateral)
-trigeminal, facial, vagus, hypoglossal
What neurons project further, those in corticobulbar or corticospinal?
corticospinal
pathways to motor neurons controlling distal muscles e.g. hands originate where in the brain?
the opposite side
What happens if their is a lower motor neuron lesion/injury in a descending pathway?
no muscle movement
describe the basal ganglia
comprimised of several interconnected sub-cortical nuclei.
linked to cerebral cortex via feedback loops
influence/ regulate output from the motor cortex
What are the 5 components of the basal ganglia?
Body of caudate nucleus ,putamen, globus pallidus, thalamus, substantia nigra
what are the three action selection centres?
corpus striatum, sub-thalamic nuclei, substania nigra
Give a disease of the basal ganglia
parkinsons disease- substantia nigra
huntingtons disease- striatum
why is the cerebellum important?
important in co-ordinating movemnets, regulates actions of antagonistic muscle groups, maintains balance
compare actual performance with what is needed
