Escape from freedom: Choosing not to choose in pigeons.

Preference for the availability of food-reinforcement alternatives was investigated with Rachlin and Green's (1972) concurrent-chains self-control paradigm. The terminal link of one chain made available a choice between immediate access to food for T seconds and delayed access to food for 4 seconds. The terminal link of the other chain provided only delayed access to food. When T was reduced to .25 seconds, pigeons began to select the delayed-access key in both terminal links. Even so, the pigeons strongly preferred constraint over choice. This effect could not be accounted for by differences in the actual amount of food obtained in the terminal links, by avoidance of the immediate-reinforcement key when not presented as part of a choice, or by avoidance of a multi-key terminal link. Rather, constraint was preferred over freedom. Apparently, the preference for choice is determined by the particular type of choice offered.