Introduction
Eyes are the visual organs that have the retina, a specialized type of brain tissue containing photoreceptors. These specialised cells convert light into electrochemical signals through the ganglion cell layer and travel along the optic nerve fibers to the brain.
Primates and many other invertebrates use three types of voluntary eye movement to track objects of interest: smooth pursuit, vergence shifts and saccades. These movements appear to be initiated by a small cortical region in the brain's frontal lobe. This is corroborated by removal of the frontal lobe. In this case, the reflexes (such as reflex shifting the eyes to a moving light) are intact, though the voluntary control is obliterated.
Read more about this topic: Eye Movement (sensory)
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