ABSTRACT
A physiological need is a deviation from an ideal set of internal conditions in the body. Drive is the psychological counterpart of a need. It is unpleasant and motivates and guides the organism to search for the incentive that reduces the drive. A psychological need, like drive, is an internal motive toward need satisfaction. Needs can exist as enduring traits because the environment lacks the means for satisfaction. Or they lie dormant until activated as need states by the appropriate stimulus. For a two-process model, psychological needs motivate behavior by need reduction (negative reinforcement) and also by added pleasure (positive reinforcement) as a consequence of need-reducing behaviors. Psychological needs are the basis for motives, such as achievement, affiliation/belonging, autonomy, closure, cognition, competence, meaning, power, and self-esteem.
