Fixation reflex

Fixation reflex

The fixation reflex is that concerned with attracting the eye on a peripheral object. For example, when a light shines in the periphery, the eyes shift gaze on it. It is controlled by the occipital lobe of the cerebral cortex, corroborated by two main tests:

# Removal of cortex causes shutdown of this reflex
# Drawing a figure on the cortex surface will cause eye movements in the very direction traveled

Older research declares that a motor pathway from the occipital cortex to the brainstem motor neurons was via the superior colliculi. This is the case in lower animals, but in humans, the theory that eye-muscle nuclei aside from the superior colliculi of the midbrain is now generally held.

When an object is focused directly at an object but the the eyes drift off their target, the fixation reflex keeps the eyes focused on the original object.

ee also

*Nystagmus
*Saccade

Bibliography

*"eye, human."Encyclopædia Britannica. 2008. Encyclopædia Britannica 2006 Ultimate Reference Suite DVD


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