Transfer of visual identity matching-to-sample in two california sea lions (zalophus californianus)

Abstract

In order to assess the abilities of two California sea lions to generalize an identity concept, both animals were taught a two-choice, visual matching-to-sample task. We hypothesized that initial identity-matching problems would be learned as conditional (if...then) discriminations but that an identity concept would emerge after training numerous exemplars of identity matching. After training with 15 two-stimulus identity matching-to-sample problems, transfer tests consisting of 15 novel problems were given to the animals. Pass-fail criteria were defined in terms of performance on Trial 1 of each test problem, performance on test trials compared with baseline trials, and performance on four-trial problem blocks. One sea lion passed on the second transfer test and the other passed on the third; both demonstrated successful generalization of an identity concept by all criteria used. A second experiment consisted of presentation of stimuli previously learned in a different context (arbitrary matching-to-sample). Both subjects immediately applied an identity concept to accurately solve these new problems. These tests conclusively demonstrate transfer of an identity matching rule in California sea lions. © 1994 Psychonomic Society, Inc.