Anatomical substrates of oculomotor control.

It is convenient to describe oculomotor neuroanatomy in terms of five to six different eye movement types, each with relatively independent neural circuitry: saccades, vestibulo-ocular reflex, optokinetic response, smooth pursuit, vergence and, most recently added to the list, gaze-holding. Current research indicates that many structures participate in several eye movement types, such as the nucleus reticularis tegmenti pontis, frontal eye fields and pretectum. However, the circuits appear to run in parallel rather than being integrated.