Comparative Psychology of Relational Cognition

• In Event: 1-198 - Acquisition of Same/Different Relations by Human and Nonhuman Groups

Integrative Statement

Comparative psychology is replete with confident proclamations of human exclusivity by eminent philosophers, including John Locke in his Essay Concerning Human Understanding: “I think, I may be positive … That the power of Abstracting is not at all in [Brutes]; and that the having of general Ideas is that which puts a perfect distinction betwixt Man and Brutes (Locke 1690/1975).” Such philosophical proclamations have recently been tested. In fact, different animal species can learn and transfer several relational discrimination problems (Wasserman et al., 2017).

One is same-different discrimination learning. Here, the evidence suggests that many species—from bees to chimpanzees—join human beings in discriminating first-order same-different relations. They can reliably report whether two or more stimuli are identical or nonidentical; they can even transfer that discrimination to untrained stimuli. Whether that capacity leverages the variability or entropy of the presented stimuli is of continuing interest (Wasserman & Young, 2010).

A more advanced problem involves second-order relations between first-order relations, possibly basic to analogical reasoning. Can only human beings discriminate such higher-order relations? Relational matching-to-sample may capture the gist of analogy: it arranges the relevant logical arguments with visual stimuli and can readily be given to animal subjects.

Early research suggested that only humans and apes can learn this problem; however, more recent work has found that crows and parrots too can solve the relational matching-to-sample task (Smirnova et al., 2015; Obozova et al., 2015). The birds were first trained on several different tasks in which they had to match individual items that were the same as one another. The birds were presented with a tray containing three cups. The middle cup was covered by a card picturing a color, a shape, or a number of items. The two side cups were also covered by cards: one the same as and one different from the middle card. The cup under the matching card contained food, but the cup under the nonmatching card was empty. Birds rapidly learned to choose the matching card and did so more quickly as they progressed from one task to the next.

Then, the critical test was given. Each card now pictured a pair of items. The middle card would display pairs AA or CD, and the two side cards would display pair BB and pair EF. The relation between one pair of items had to be appreciated and then applied to a new pair of items to generate the correct answer: the BB card in the case of AA or the EF card in the case of CD. Not only did the birds correctly perform this task, but they did so from the very first presentations, without explicit training! It is possible that initial training to match identical items may have enabled the birds to grasp a broadly applicable concept of sameness which they could apply to the novel two-item analogy task. Such robust and uninstructed relational matching-to-sample behavior represents the first convincing evidence of analogical reasoning in a non-primate animal.

Author

• Edward Wasserman, University of Iowa
  Presenting Author