AP BIOLOGY

Detailed explanation-1: -The eye blink elicited by electrical stimulation of the median nerve at the wrist hand-blink reflex (HBR) is a defensive reflex subserved by an entirely subcortical circuit at brainstem level (Miwa et al., 1998, Valls-Solé et al., 1997).

Detailed explanation-2: -Eye blinking is one of the most frequent human actions. The control of blinking is thought to reflect complex interactions between maintaining clear and healthy vision and influences tied to central dopaminergic functions including cognitive states, psychological factors, and medical conditions.

Detailed explanation-3: -The corneal reflex, also known as the blink reflex or eyelid reflex, is an involuntary blinking of the eyelids elicited by stimulation of the cornea (such as by touching or by a foreign body), though it could result from any peripheral stimulus.

Detailed explanation-4: -Contact with the cornea initiates 2 reflexes: blink reflex (corneal reflex) and tear production. The corneal blink reflex is caused by a loop between the trigeminal sensory nerves and the facial motor (VII) nerve innervation of the orbicularis oculi muscles.