Evidence of non-circadian timing in a low response-cost daily Time-Place Learning task with pigeons Columba Livia

• Published in: Behavioural processes 2019-11, Vol.168, p.103942-103942, Article 103942
• Main Authors: García-Gallardo, Daniel, Aguilar Guevara, Francisco, Moreno, Sergio, Hernández, Mitzi, Carpio, Claudio
• Format: Article
• Language: English
• Subjects: Animals; Circadian Rhythm; Circadian timing; Columbidae; Mental Recall; Motivation; Ordinal timing; Orientation; Pigeon; Reinforcement Schedule; Space Perception; Spatial Memory; Time Perception; Time-Place Learning
• ISSN: 0376-6357; 1872-8308
• DOI: 10.1016/j.beproc.2019.103942

•We assessed the effects of response cost in a daily TPL Task with pigeons.•Birds obtained food on one feeder in the morning and on other in the afternoon.•Feeders were near each other for one group and far from each other for other group.•Morning sessions were skipped for afternoon tests and viceversa.•Pigeons showed a tendency to rely on a non-circadian strategy when the response cost was low. Previous research has shown that rats require high response cost in order to display circadian timing in daily Time-Place Learning (TPL) tasks. For many possible reasons, no explicit effort to explore the effects of response cost on the performance of other species in these tasks has been made. Therefore, the present paper explores the effects of response cost on pigeon’s performance on a daily TPL task. Head entry responses were reinforced according to a Random Interval schedule of reinforcement on one feeder during morning sessions and on another feeder during afternoon sessions. Feeders were located 8 cm apart for one group of birds (Group Near) and 56 cm apart for another group (Group Far). After 50 training sessions, testing began. Test sessions consisted of skipping either the morning or the afternoon session. Results show that most birds in the near group respond primarily on the opposite feeder during the first 20 s of the test sessions and then they switch to the correct feeder. On the other hand, most birds in Group Far respond at the same rate on both opposite and correct feeders during 20 s, and then they respond primarily on the correct feeder. The possibility of these data revealing non circadian timing for birds in a low response-cost daily TPL task is discussed along with the implications of such a finding for previous literature that claims that this type of performance could be unique to rats.