Effect of Interpolated Temporal Activity on Temporal Short-Term Memory

The purpose of this research was to determine the retroactive interference effects of a single interpolated task (i.e., one temporal duration) on the retention of a criterion duration. This research is of interest because the mnemonic structure of temporal information of different durations is uncertain. Previous research has indicated that there might be a difference in structure for durations of 1 and 4 sec., although the results are inconsistent. Thus, two criterion durations of 1 and 4 sec. and five interpolated durations (i.e., 60%, 80%, 100%, 120%, and 140% of the duration of the criterion) were utilized under the method of reproduction. In addition, subjects were instructed to use either a counting strategy or none (referred to as conscious time estimation) to facilitate the retention of the temporal information. Recall was less variable when using a counting strategy than not and when estimating 1 sec. than 4 sec. However, there was no effect of interpolated activity when comparing performance across different interpolated conditions (no interpolated activity). Apparently, one interpolated duration is not sufficient to produce structural interference with a single criterion duration.

An Examination of Self-Pacing Procedures in Human Time Estimation

The main purpose of the present research was to investigate the role of self-pacing trial procedures in time estimation. Auditory durations of 1, 4, and 8 sec. were estimated by 12 subjects under the method of reproduction. Different features of performance were investigated using several dependent variables. When left to themselves, subjects chose a relatively short intertrial interval, the duration of which did not differ across the three criterion durations. This finding seemed best explained as an attempt by the subjects to minimize boredom and maximize alertness. Also, subjects waited for a short time before reproducing the criterion duration, and again this period did not differ across the three criterion durations. A significant relationship was found between the duration of the self-paced intertrial interval and self-paced retention interval for all criterion durations. It appeared that subjects were attempting to maximize their time-estimation performance by either minimizing the retention interval or by developing a trial-interval rhythm. Finally, subjects were more variable in their estimates as the criterion duration increased.