反射是神经活动的最基本方式，是指有机体的中枢神经对外界刺激所做出的有规律的应答。也是一切心理与行为的生物学基础。

• 保护生命／器官，如眨眼反射便是为了保护眼睛。

A reflex action, differently known as a reflex, is an involuntary and nearly instantaneous movement in response to a stimulus. Scientific use of the term "reflex" refers to a behavior that is mediated via the reflex arc; this does not apply to casual uses of the term "reflex".