Model of an oculomotor subsystem

One of the complex control systems present in the human body is the oculomotor control system. There are two major modes of ocular movements, viz. saccadic and smooth pursuit. More knowledge about the neuromuscular mechanisms controlling these eye movements is obtained if experiments are carried out on subjects whose two types of eye movements are differentially affected due to disorders at their higher centres of control. Eye movements of patients with a novel form of Heredo-familial Spinocerebellar Degeneration have been measured and quantified. These have been compared with those of normal subjects. Subsequent analysis indicates a continuous fourth order transfer function for the smooth pursuit eye-in-skull movements in the horizontal plane with head stationary.