Which of the following is involved in equilibrium, gait, and learning induced changes in vestibuloocularreflex?
Correct Answer: Vestibulocerebellum
Description: Ans. A. Vestibulocerebellum. (Ref. Guyton & Hall's Textbook of Medical Physiology 11th/pg. 703 - 705).Function of the Cerebellum in Overall Motor Control:The nervous system uses the cerebellum to coordinate motor control functions at three levels, as follows: Part of cerebellumConsist ofFunction1The vestibulocerebellumConsists principally of the small flocculonodular cerebellar lobes (that lie under the posterior cerebellum) and adjacent portions of the vermis.It provides neural circuits for most of the body's equilibrium movements.2The spinocerebellumConsists of most of the vermis of the posterior and anterior cerebellum plus the adjacent intermediate zones on both sides of the vermis.It provides the circuitry for coordinating mainly movements of the distal portions of the limbs, especially the hands and fingers.3The cerebrocerebellumConsists of the large lateral zones of the cerebellar hemispheres, lateral to the intermediate zones. It receives virtually all its input from the cerebral motor cortex and adjacent premotor and somatosensory cortices of the cerebrum.It transmits its output information in the upward direction back to the brain, functioning in a feedback manner with the cerebral cortical sensorimotor system to plan sequential voluntary body and limb movements, planning these as much as tenths of a second in advance of the actual movements. This is called development of "motor imagery" of movements to be performed.Vestibulocerebellum--Its Function in Association with the Brain Stem and Spinal Cord to Control Equilibrium andPostural Movements# The vestibulocerebellum originated phylogenetically at about the same time that the vestibular apparatus in the inner ear developed. Furthermore, loss of the flocculonodular lobes and adjacent portions of the vermis of the cerebellum, which constitute the vestibulocerebellum, causes extreme disturbance of equilibrium and postural movements.# The vestibulocerebellum is especially important in controlling balance between agonist and antagonist muscle con- tractions of the spine, hips, and shoulders during rapid changes in body positions as required by the vestibular apparatus.# It is then the function of the vestibulocerebellum to calculate in advance from these rates and directions where the different parts will be during the next few milliseconds. The results of these calculations are the key to the brain's progression to the next sequential movement.
Category:
Physiology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now