Learning any relatively durable change in behaviour or knowledge that is due to experience. Phobias irrational fears of specific objects or situations. Result of another learning process termed classical conditioning. Agoraphobia intense fear of being in public places where it may be difficult to escape from or in which it might be difficult to obtain help. Conditioning involves learning connections between events that occur in an organism"s environment. Classical conditioning type of learning in which stimulus acquires capacity to evoke response that was originally evoked by another stimulus (sometimes called pavlovian conditioning) He showed how learning was under influence of experience and that associations could be built up in consciousness . He created an apparatus to demonstrate classical conditioning. When evoked by the cs (tone), salivation was the cr. When evoked by the ucs (meat powder), salivation was ucr. Unconditional stimulus (usc) stimulus that evokes an unconditioned response without previous conditioning.