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Pleasure and Pain

The motivation to pursue pleasure and avoid pain is not exclusively biological, but it is strongly influenced by biological factors. The idea that organisms are motivated to pursue pleasure and avoid pain was proposed by the Greek philosopher Epicurus, who called this hedonism. In present day theories, the pursuit of pleasure and avoidance of pain are conceived as components of a control system.

The opponent process theory

When a system must be delicately controlled, this is best accomplished with two forces that act in opposite directions. For example, a car needs both an accelerator and a brake. You can regulate speed rather slowly and clumsily using only an accelerator, but this is not enough to coordinate the speed of a car in traffic. Similarly, the automatic control systems of the body require opponent processes: controls that push in opposite directions.

What are opponent processes in the hedonic system? What is hedonic contrast?

Pleasure and pain are powerful but opposed parts of a hedonic (pleasure/pain) control system that regulates motivation. Richard Solomon of the University of Pennsylvania suggested they should be regarded as opponent processes similar to an accelerator and brake.

Hedonic contrast is one of the phenomena Solomon explains with the opponent process theory. This is the tendency of the pleasure/pain control system to rebound in the opposite direction after an intense experience of either pleasure or pain. For example, my young children often cried or got cranky in the afternoon on Christmas Day, a few hours after we opened presents in the morning. They were not unhappy with their presents; they were just on the rebound from an intensely joyful morning.

The same thing can occur in the other direction. Sometimes one feels a burst of relief and pleasure after finishing a difficult task, such as a final exam. One's emotions act as if they are on the rebound from all the stress and bad feelings that came before, so now one feels relief and pleasure.

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