The pathology of boredom.

I f you shake the surface on which a snail is resting, it withdraws into its shell. If you shake it repeatedly, the snail after a while fails to reactIn the same way a sea anemone which is dis­ turbed by a drop of water falling on the water surface above it ceases to be dis­ turbed if drops continue to fall; a bird stops flying away from a rustling motion if the motion is steadily repeated. Most organisms stop responding to a stimulus repeated over and over again (unless the response is reinforced by reward or avoidance of punishment). Indeed, the higher organisms actively avoid a com­ pletely monotonous environment. A rat in a maze wiII use different routes to food, if they are available, rather than the same one all the time. It will tend to avoid areas in which it has spent con­ siderable time and to explore the less familiar areas. Monotony is an important and endur­ ing human problem. Persons who have to work for long periods at repetitive tasks often complain of being bored and dissatisfied with their jobs, and frequent­ ly their performance declines. During the last war N. H. Mackworth of Eng­ land made a series of researches for the Royal Air Force to find out why radar operators on antisubmarine patrol some­ times failed to detect U-boats. The oper­ ators usually worked in isolation, watch­ ing a radar screen hour after hour. Mackworth set up a comparable labora­ tory situation, requiring subjects to watch a pointer moving around a gradu­ ated dial and to press a button whenever the pointer made a double jump. The subjects' efficiency declined in the sur­ prisingly short time of half an hour. As a result of this and other research the radar operators' tour of duty was short­ ened. In this age of semi-automation, when