COMMITMENT USING PUNISHMENT

Experimental parameters were adjusted so that pigeons' pairwise choices among three alternatives reflected the following order of preference: (a) a smaller‐sooner reinforcer, (b) a larger‐later reinforcer, and (c) the smaller‐sooner reinforcer followed by a punishment (consisting of an extended blackout period). After this order of preference was established, the pigeons were exposed to a two‐link, concurrent‐chain‐like choice procedure. One terminal link consisted of a choice between the smaller‐sooner and the larger‐later reinforcer; the other terminal link was identical to the first except that the smaller‐sooner reinforcer was followed by blackout punishment. The pigeons' preference (in their initial‐link choice) for the terminal link with the punished smaller‐sooner alternative increased as the delay between the initial and terminal links increased. By choosing this terminal link, the pigeons are said to have “committed” themselves to obtaining the larger‐later reinforcer. However, unlike prior studies of commitment (e.g., Rachlin & Green, 1972), it was still possible after making the commitment for the pigeons to choose the smaller‐sooner reinforcer and undergo the punishment. The pigeons did in fact occasionally make this highly deleterious choice.