Proactive effects in pigeons' memory for event duration: Evidence for analogical retention.

Abstract

An intrairial proactive interference design was used to examine the nature of pigeons' memory for duration in a delayed matching task. Short (2 s) or long (10 s) target samples were preceded on test trials by a short or long presample. The durations were consistent on some trials (shortshort or long-long) and inconsistent on others (short-long or long-short). Contrary to predictions based on prospective or categorical coding, accuracy was not related to duration consistency. Instead, accuracy was reduced on short-short and long-short trials and somewhat enhanced on short-long and long-long trials, suggesting that the pigeons "summed across" the durations. This occurred even with a 10-s interstimulus interval (Experiment 1) and even when the presample and target sample were physically distinct (Experiment 2). These results suggest that pigeons remember event durations in an analogical and retrospective fashion.