Differential reinforcement of perching duration in the pigeon : a comparison with differential-reinforcement-of-low-rate key-pecking

Pigeons were required to jump on a perch and sit on it for a specified duration before stepping off, in order to gain access to food. This duration was progressively increased by 1-sec steps. Median response duration approximated the required repsonse duration up to values of 40 or even 50 sec and efficiency remained high. Response duration distribution had sharp peaks and comparable dispersions throughout the critical values range. These results contrast with the performance of the same birds in a conventional differential-reinforcement-of-low-rate schedule involving a key-peck response. This indicates that pigeons are able to regulate in time their own motor behaviour over much longer time intervals in the case of a perching response than in the case of key-pecking.