Claim: A reflex is made possible by reflex arcs, which can act on an impulse before it reaches the brain.

A reflex , or reflex action , is an involuntary and nearly instantaneous movement in response to a stimulus . A reflex is made possible by neural pathways called reflex arcs which can act on an impulse before that impulse reaches the brain . The reflex is then an automatic response to a stimulus that does not receive or need conscious thought .