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CEREBELLUM. The cerebellum is not necessary for either perception or motor function; rather, it regulates movement and posture by adjusting the output of the descending motor systems of the brain. The cerebellum achieves its function by acting as a comparator which corrects for errors in
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CEREBELLUM The cerebellum is not necessary for either perception or motor function; rather, it regulates movement and posture by adjusting the output of the descending motor systems of the brain. The cerebellum achieves its function by acting as a comparator which corrects for errors in performance with respect to intention. Lesions of the cerebellum affect coordination of limb and eye movements, impair balance and decrease muscle tone.
CEREBELLUM 2 Functionally, the cerebellum is divided into three divisions: Vestibulocerebellum - receives input from the vestibular nuclei in the medulla and projects directly back to them. It governs eye movement and body equilibrium during stance and walking. Spinocerebellum - receives input from the periphery. It affects descending motor systems and thereby helps control the execution of limb movements. Cerebrocerebellum - receives inputs from nuclei in the pons (mid-brain). Its output goes by way of the thalamus to the motor cortex to help in planning and initiating movements.
CEREBELLUM 3 Lesions of the dentate nucleus or the cerebellar cortex result in 4 kinds of problems: Delays in initiating and terminating movements Tremor at the end of movement (hypermetria caused by (i) ) Disorders in temporal coordination of movements involving several joints (posture required to perform a motor task) Disorders in spatial coordination of hands and fingers (tremor without motor act) From these deficits, we can see the function of the cerebellum.