Matching within and between sense modalities in the monkey (Macaca mulatta).

Abstract

Rhesus monkeys were trained on a series of visual matching problems and tested for cross-dimensional transfer. Performance of a true matching group was at the same time compared with that of a "false matching" (i.e., conditional reaction) group. Training was then given on a series of cross-modal (visual-tactual) matching (CMM) problems, again with true vs. false matching comparisons. Finally, a test for CMM using a single-sample technique was given. Evidence was found for cross-dimensional transfer of visual matching, but none for differences between initial true and false visual, or cross-modal, matching tasks. Nor was evidence for a genuine CMM ability found in the results of the single-sample CMM tests.Ettlinger and Blakemore (1967) performed two experiments designed to test cross-modal matching (CMM) in the rhesus monkey. In neither experiment was evidence found for such matching. Although their animals were able to learn to select the matching choice object after responding to one or the other sample, they did so no more readily than animals trained to make their choice response conditional upon unrelated samples. (If sample = A, choose C; if sample = B, choose D. Such a "false matching" task can only be learned on a conditional reaction basis; if animals learned "true matching" tasks on such a basis they would be expected to do so at a similar rate.) More recently, however, Rogers (1970, 1971) have presented evidence for CMM in apes. After lengthy previous training, two chimpanzees and one orangutan were able to perform at a level significantly better than chance when presented with a series of 40 single-trial (thus excluding intraproblem learning) "junk object" CMM problems. In the second study 1 The author is grateful to G. Ettlinger and R. E. Passingham for their helpful suggestions at all stages of this work, and for their comments on the manuscript; he also thanks B. Frost for her assistance in the later stages of training. This report describes work done in partial fulfillment of the requirements for the PhD degree (Milner, 1971). The research was supported by Medical Research Council, England, Grant G. 966/23/B.2 Requests for reprints should be sent to A.

On the Limits of the Matching Concept in Monkeys (Cebus Apella)

“…Failures of the matching concept to transfer from one sensory modality to another are well documented (e.g., Milner, 1973;Salmon, 1984), and the present results, in conjunction with our earlier findings , suggest that a similar limitation applies to the visual modality itself, at least insofar as static and dynamic stimuli are concerned. However, such judgments do not appear to be very abstract.…”

The Transfer of Information between Sense-Modalities: A Neuropsychological Review

“…Its basic defect lies in the ambiguity of the requirements when the stimuli are introduced in the second modality: no indication is given to the subject that the previous experience with these (or analogous) stimuli is to be taken into account. Cross-modal matching, on the other hand, is generally assessed (DAVEN-PORT and ROGERS, 1970;MILNER, 1972) only when the subject has given some prior indication of having learnt that it is expected to match. (It is of course easy to be wise after the event.…”

Processing of identity and conditional relations in monkeys (Cebus apella) and pigeons (Columba livid)

“…As revealed by transfer tests to new stimuli, monkeys can develop the matching concept in the visual modality with training on as few as two exemplars (D'Amato, Salmon, & Colombo, 1985). But the limited generality of the concept is revealed by the fact that, without additional extensive matching training in the target modality, it does not extend to audition (D'Amato & Colombo, 1985), or, apparently, to touch (Milner, 1973). And within the visual modality itself, unless extended by further relevant training, the identity concept seems largely limited to the general class of stimuli with which it was developed, at least in cebus monkeys (D'Amato, Salmon, & Colombo, 1985).…”