Is “refraining” from eating free food a case of self-controlled behavior in pigeons?

Abstract

Self-controlled eating behavior was studied in three food-deprived pigeons exposed to a procedure consisting on fifty 64-s time cycles (T cycles). In each cycle a food-hopper was always presented once for 3 s (S^R₁) and could be presented for other 3 s (S^R₂) after the T cycle elapsed, according to the following contingency. If the subject approached to S^R₁ it was withdrawn and S^R 2 delivery was cancelled; otherwise S^R₂ was presented when the T cycle elapsed. In five experimental phases S^R₁ was presented 3, 32, 16, 8, and 3 s before the end of the T cycle. Additionally, according to an ABA-design, a color change of a response key signaled (conditions A1 and A2) or not (condition B) S^R₁ presentations and served as a distracting operandum. It was found that the number of S^R₂ obtained was lower as SR 1 was presented closer to the beginning of each T cycle, regardless of signaling S^R₁ presentations. It was also found that only in the A conditions of the first experimental phase (3 s) S^R₁ interruptions were relatively low and R>0 of key pecks was comparatively high. Globally, these results replicated and extended those of previous studies in which self-controlled eating behavior was explored.