The difference between dishabituation and sensitization is in the strength and timing of the response. Dishabituation involves the recovery of the original response after it has been lost or lessened, while sensitization produces a response stronger than the original one that was never lost in the first place.

The ringing of the bell was the CS because it was not directly connected to the desired response, salivation. The presentation of food was the UCS, because salivation at the presentation serves a purpose and is a normal response to this stimulus.

Salivation upon the ringing of a bell was the CR because such salivation serves no purpose without the presence of food. Salivation at the presentation of food was the UCR because this salivation serves a purpose directly related to that stimulus.

In classical conditioning, the animal receives no benefit from associating the CS with the UCS. However, in operant conditioning, an unassociated behavior becomes associated with a reward.