The effects of active and passive processing of interval events on prospective and retrospective time estimates

Abstract

Four experiments assessed the relationship between time estimates of moderately long intervals and the number of interval events (stimulus quantity) as a function of whether overt responses to the interval events were (active processing) or were not (passive processing) required. The relationship was assessed in the prospective (Experiments 1–4) and in the retrospective paradigms (Experiments 1 and 2). The visual interval events were geometric patterns (Experiment 1), lines (Experiments 2 and 4) or words (Experiment 3). In Experiments 1, 2, and 3 the subjects estimated the relative duration of two equally long intervals (48 sec each), and in Experiment 4 they estimated the absolute durations of three different intervals (12, 28, and 48 sec). Retrospective time estimates were positively related to stimulus quantity under both active and passive processing conditions (Experiments 1 and 2). Prospective time estimates were negatively related to stimulus quantity under active processing conditions (Experiments 1, 2, and 3) and either negatively related (Experiment 1) or unrelated (Experiments 2 and 3) under passive processing conditions. The results of Experiment 4 indicated that absolute time estimates of the longer intervals were influenced by the intervals' content and by processing activity; relative to time estimates of ‘empty’ intervals, time estimates of the ‘filled’ intervals were shorter in both the active and passive processing conditions. The results are discussed with reference to cognitive models of time estimation with particular reference to the attentional/disruption models of prospective timing.