Shared Attention in Pigeons: Retrieval Failure Does Not Account for the Element Superiority Effect

Abstract

Matching-to-sample accuracy by pigeons is generally poorer on compound-sample trials (when only one of the elements is tested) than on element sample trials. This phenomenon, known as the element superiority effect (ESE), has been attributed to the pigeon's limited capacity to process the sample. Recently, a retrieval failure account has been suggested (Lamb, 1991): it takes the pigeon longer to retrieve the relevant element when there are two elements rather than one in memory. In the present research, little support for a retrieval failure account of the ESE was found. Neither extending the period of comparison responding by using a successive matching task (Experiment 1), nor examining normal variations in the magnitude of the pigeons’ comparison choice latency in a simultaneous matching task (Experiment 2), nor forcing the pigeon to delay its choice of comparisons (Experiment 3), significantly affected the magnitude of the ESE. The present results are consistent with an attentional (limited processing capacity) account of the ESE.