THE PYRAMIDAL AND EXTRA PYRAMIDAL TRACTS (DESCENDING TRACTS) :::
Once the decisions are made in the brain many of themartran stted through messages that pass down through the pyramidal and tracts They form the major descending tracts
The pyamidal tracts originate from the cortex of the cerebrum and pass through the internal capsule cerebral peduncle pons and medulla to the spinal cord some of the fibres that are crossed at the level of medulla oblongata enter the lateral white column of the spinal cord The fibres which do not cross in the medulla obongata enter the anterior white column of the spinal cord
The pyramidal tracts the longest motor tracts of the body convey the motor impulses to the spinal cord for controlling the voluntary movement of many parts of the body especially the movement of fingers and hand subserving skilled work They also form a part of the pathways for superficial reflexes like cremasteric abdominal and plantar reflexes
The extrapyramidal tracts are those motor pathways which may act as the alternate route for the volitional impulses and form the platform on which the pyramidal system works skillfully
The extrapyramidal tracts are found in the mid brain originating from the red nucleus tectum vestibular part and certain parts of the cerebral cortex the tracts finally descend to the spinal cord three functions of the extrapyramidal tracts are as follows :
1.Control of the movements of the eye balls
2.Control of tone posture and equilibrium
3.Co-ordination of the finer movements e.g movements e.g movements of limbs while walking
4.Inhibition of the lower centres
5.TO work as the substitute for the pyramidal tracts when they are damaged
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