Unlearned or Unconditioned Motivative Operations


Motivative Operations for reinforcers like food and drink (unlearned reinforcers) involve two principles, satiation and deprivation. Deprivation has an establishing effect on reinforcer value and will tend to evoke the behaviors associated with the reinforcer. Some examples of these phenomena include:

  • After being under water in a pool for more than a few seconds, the body becomes deprived of air (oxygen). The effect of oxygen deprivation is to establish air as a reinforcer. Likewise the effect of oxygen deprivation is to evoke behaviors that result in obtaining air, such as swimming to the surface.
  • After not eating for several hours, food is likely established as a reinforcer. The person who is food deprived will be more likely to engage in behaviors that result in obtaining food, such as walking to the refrigerator, driving to a restaurant, or asking someone else for food.
  • When one eats salty pretzels (causing water deprivation), drinking water becomes of value and will likely lead to engagement in any behavior that has produced water in the past.

On the other hand having enough of something to eat or drink leads to satiation. Satiation has an abolishing effect on reinforcer value. This means that the person will be less likely to do things to obtain that reinforcer.


Some examples of satiation include:

  • Drinking sufficient water will eventually lead to satiation and a reduction in the value of water as a reinforcer. Therefore the person will be less likely to ask for water.
  • For a child who has just eaten lunch, food will be of less value and he or she will be less likely to ask for food.


It is probably important to teach mands for food or drink at times when the student has not had food or drink for some period of time. Likewise this principle implies that more mands will be emitted if the food or drink is delivered in small increments rather than all at once (more generous portions may lead to more rapid satiation.) Of course, the use of food and drink as reinforcers must be done with care. It is not ethical to deny individuals their basic needs. However, training mands at times when students are naturally hungry is appropriate as long as attention is paid to nutritional issues and is not contra-indicated by any parental or cultural preference or dietary factor.