In biology, an automatic and inborn response to a stimulus that involves a nerve impulse passing from a sensory nerve cell to a muscle or gland without reaching the level of consciousness. Simple reflexes include sucking, swallowing, blinking, scratching, and the knee jerk. Most reflexes consist of complex patterns of many unconsciously coordinated muscular actions that form the basis of much instinctive behavior in animals. Examples include walking, standing, the cat's righting reflex, and basic sexual acts.
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A reflex action, also known as a reflex, is an involuntary and almost instant movement in response to stimulus. In most contexts, especially involving humans, a reflex action is mediated via the reflex arc (although this is not always true in other animals, or in more casual usage of the term 'reflex'.)
Reflex actions include:
|Pupillary light reflex||II||III|
|Jaw jerk reflex||V||V|
|Corneal reflex, also known as the blink reflex||V||VII|
|Caloric reflex test/Vestibulo-ocular reflex||VIII||III, IV, VI +|
Newborn babies have a number of other reflexes which are not seen in adults, referred to as primitive reflexes. These include: