Corneal reflex
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2008-05-29T07:56:33Z
Schu1321
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The '''corneal reflex''', also known as the '''blink reflex''', is an involuntary [[blink]]ing of the [[eyelid]]s elicited by stimulation (such as touching or a foreign body) of the [[cornea]]. Stimulation should elicit both a direct and consensual response (response of the opposite eye). The [[evolution]]ary purpose of this reflex is to protect the [[eye]]s from foreign bodies and bright lights. The blink reflex also occurs when sounds greater than 40-60 [[Decibel|dB]]<ref>Garde, M.M., & Cowey, A. (2000). ''"Deaf hearing": Unacknowledged detection of auditory stimuli in a patient with cerebral deafness. Cortex 36''(1), 71-80</ref>.
The reflex is mediated by:
* the nasociliary branch of the [[ophthalmic nerve|ophthalmic branch]] (V<sub>1</sub>) of the 5th [[Cranial nerves|cranial nerve]] ([[trigeminal nerve]]) sensing the stimulus on the cornea,
* the 7th cranial nerve ([[facial nerve]]) initiating the motor response.
Use of [[contact lens]]es may diminish or abolish this reflex.
The examination of the corneal reflex is a part of some [[Neurology|neurological]] exams, particularly when evaluating [[coma]]. Damage to the ophthalmic branch (V<sub>1</sub>) of the 5th cranial nerve results in absent corneal reflex when the affected eye is stimulated. Stimulation of one cornea normally has a consensual response, with both eyelids normally closing.
==See also==
*[[Reflex action|Reflex]]
==References==
<references />
==External links==
* {{GPNotebook|-751501308}}
{{Reflex}}
[[Category:Reflexes]]
[[pl:Odruch rogówkowy]]