Q.What is the function of red nucleus?

The midbrain lies between the diencephalon and the pons varolii and houses the cerebral aqueduct (iter), the canal linking the third and fourth ventricles. Its dorsal surface bears the corpora quadrigemina, four rounded elevations: the upper superior colliculi mediate visual reflexes, and the lower inferior colliculi act as relay centres for auditory reflexes (e.g. turning the head toward a sound). Its inferior surface carries two thick fibre tracts, the cerebral peduncles (crura cerebri), which link the cerebrum to the midbrain by carrying ascending and descending RAS fibres. Centrally, a mass of grey matter within the white matter forms the red nucleus, important in controlling posture, muscle tone, and the fine-tuning and coordination of motor activity.