Dissociation of Procedural and Working Memory in Pigeons (Columba livia)

Abstract

A new method was developed to concurrently investigate procedural memory and working memory in pigeons.  Pigeons performed a sequence of keypecks across 3 response keys in a serial response task, with periodic choice probes for the location of a recently produced response.  Procedural memory was operationally defined as decreasing response times to predictable cues in the sequence.  Working memory was reflected by accurate responses to the choice probes.  Changing the sequence of required keypecks to a random sequence interfered with procedural memory in the form of slowed response times, but did not prevent pigeons from effectively using working memory to remember specific cue locations.  Conversely, changing exposure duration of to a cue location influenced working memory but had no effect on procedural memory.  Double dissociations such as this have supported the multiple systems approach to the study of memory in cognitive psychology and neuroscience, and they encourage a similar approach in comparative psychology.