A process of behavior modification by which a subject comes to respond in a desired manner to a previously neutral stimulus that has been repeatedly presented along with an unconditioned stimulus that elicits the desired response.经典性条件反射：一种行为改变的过程，通过该过程一个主体对先前的神经刺激产生期望的方式，该刺激已和能引发期望反应的非条件刺激一起重复地出现