Emotions play no adaptive role but rather represent a learned response, acquired through classical and operant conditioning.
The focus of behaviorist theories is learning. Emotions, to the extent that they are of interest at all, are considered to be another form of learned behavior, acquired through classical or operant conditioning, and not requiring cognitive involvement. Observable emotional behavior, such as sweating, rapid heart beat, or blushing, can become associated with a stimulus through operant conditioning; i.e., seeing a dangerous stimulus may cause us to run, which increases the heartbeat, and eventually seeing the stimulus may be adequate to increase the heartbeat without the running behavior. Emotions are considered epiphenomanal, are not thought to be involved in motivation of behavior, and in any case cannot be the object of serious study because they are largely unobservable. More recent behaviorist theories take a broader view and acknowledge that emotional responses are in part instinctive and may have an adaptive value. These theorists view emotions as drives, linked to results of goal-directed behavior (Mowrer, 1960); basic drives are: fear, hope, relief, and disappointment, each linked to specific situations.