title: Does absolute brain size really predict self-control? Hand-tracking training improves performance on the A-not-B task.
abstract: Large-scale, comparative cognition studies are set to revolutionize the way we investigate and understand the evolution of intelligence. However, the conclusions reached by such work have a key limitation: the cognitive tests themselves. If factors other than cognition can systematically affect the performance of a subset of animals on these tests, we risk drawing the wrong conclusions about how intelligence evolves. Here, we examined whether this is the case for the A-not-B task, recently used by MacLean and co-workers to study self-control among 36 different species. Non-primates performed poorly on this task; possibly because they have difficulty tracking the movements of a human demonstrator, and not because they lack self-control. To test this, we assessed the performance of New Caledonian crows on the A-not-B task before and after two types of training. New Caledonian crows trained to track rewards moved by a human demonstrator were more likely to pass the A-not-B test than birds trained on an unrelated choice task involving inhibitory control. Our findings demonstrate that overlooked task demands can affect performance on a cognitive task, and so bring into question MacLean's conclusion that absolute brain size best predicts self-control.
authors: School of Psychology, University of Auckland, Auckland, New Zealand s.jelbert@auckland.ac.nz.
authors: S A
authors: http://orcid.org/0000-0002-7503-0648
authors: SA
authors: Jelbert
authors: School of Psychology, University of Auckland, Auckland, New Zealand.
authors: A H
authors: http://orcid.org/0000-0003-3492-7667
authors: AH
authors: Taylor
authors: School of Psychology, University of Auckland, Auckland, New Zealand Max Planck Institute for the Science of Human History, Jena, Germany Research School of the Social Sciences, Australian National University, Canberra, Australia.
authors: R D
authors: RD
authors: Gray
mesh_terms: D000818:Animals; D001921:Brain / Q000033:anatomy & histology*; D002755:Choice Behavior; D046368:Crows / Q000502:physiology*; D005106:Exploratory Behavior; D005260:Female; D008297:Male; D012201:Reward; D000068356:Self-Control
keywords: New Caledonian crows; comparative cognition; corvids; evolution of intelligence; primates; self-control