Michel Guay

Human time estimation: Procedural effects

The purpose of this experiment was to investigate the effects of various trial procedures on human time estimation. Four different procedures were used: (1) experimenter-paced intertrial interval/experimenter-paced retention interval, (2) self-paced intertrial interval/experimenterpaced retention interval, (3) experimenter-paced intertrial interval/self-paced retention interval, and (4) self-paced intertrial interval/self-paced retention interval. Auditory time lengths of 1, 4, and 8 sec were estimated by the method of reproduction. Results showed that the two self-paced retention interval conditions produced a typical range effect in that the 1-sec criterion duration was overestimated and the 4- and 8-sec durations were underestimated. In addition, the two homogeneous trial conditions (i.e., procedures 1 and 4 above) produced more accurate time estimation performance than did the two heterogeneous conditions. Variable error increased as the duration of the time to be estimated increased, and subjects were more variable under the two experimenter-paced retention interval conditions than under the two self-paced conditions. We concluded that the self-paced intertrial interval/self-paced retention interval condition seems to be the best procedure to maximize time-estimation performance.

The Effects of Different Knowledge of Results Spacing and Summarizing Techniques on the Acquisition of a Ballistic Movement

The present study crossed three knowledge of results summarizing techniques (single-trial KR, summary KR, and average KR) with two spacing conditions (KR on every fifth trial-20%- and KR on every trial-100%). Participants (n = 10 per group) performed 80 acquisition trials of a ballistic movement task involving both a temporal and spatial goal, followed by 30 immediate (10 min) and 30 delayed (2 days) no-KR transfer trials. For the spatial goal, performance was less accurate (absolute constant error) for the 20% spacing condition than the 100% condition during acquisition, but more accurate during delayed transfer. No effects were significant for variable error. For the temporal goal, performance was more accurate for the summary and average conditions than the single-trial KR condition; however, this effect was only present within the 20% spacing condition and only during Block 1 of acquisition. A similar effect held for variable error as well, except that the effect persisted for acquisition and transfer. It was concluded that the spacing of KR is more influential in promoting spatial accuracy than the summarizing of KR.

Proactive Interference and Intertrial Interval in Short-Term Retention of Temporal Visual Information

The main purpose was to examine the role of proactive interference in temporal short-term memory when subjects experienced time under a conscious cognitive strategy for time estimation, made without time-aiding techniques. Visual durations of 1, 4, and 8 sec. were estimated by 18 subjects under the method of reproduction. Three retention intervals were used: immediate reproduction, 15, and 30 sec. of rest. The three intertrial intervals were immediate, 15, and 30 sec. Constant error was used as an index of bias. The constant errors provided no indication that proactive interference was operating in temporal short-term memory. The lack of proactive interference was not associated with intertrial intervals; even when the intertrial intervals were shortened to 1 sec. no proactive interference was observed. Variable error was used to evaluate effects of forgetting. The variable errors for the 4- and 8-sec. durations seemed amenable to a trace-decay explanation.

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.

Weber's Law for the Reproduction of Temporal Information

The main purpose of this research was to determine the numeric values of Webers fraction when subjects were required to estimate temporal durations of 1, 3, 5, 7, and 9 sec. under the method of reproduction. The results provided evidence in support of a constant coefficient of proximity for time estimation of approximately 14.5%.

Counting Strategies and Assimilation Effects in Short-Term Retention of Temporal Information

The purpose of the present research was to examine proactive interference in general and assimilation effects (i.e., shifts in constant error caused by prior responses) in particular, when subjects used covert counting to aid their retention of the temporal information. Visually presented durations of 1, 4, and 8 sec. were estimated by 18 subjects under the method of reproduction. Three retention intervals (i.e., immediate, 15, and 30 sec.) and three intertrial intervals (i.e., immediate, 15, and 30 sec.) were employed. Analysis of constant error provided no indication that proactive interference was operating in the retention of temporal information as there was no increase in error across trials, no increase in error for longer retention intervals, and no interaction between trials and retention intervals. Also, there was no change in variable error as the retention intervals lengthened for any temporal duration except for the 4-sec. criterion. Finally, the rate of counting (counting units/sec.) was different across the durations to be remembered. The major conclusion of the present research was that counting greatly facilitates retention of temporal information as compared to retention without such a time-aiding strategy.

Relationship between Psychomotor Functioning and Health Status among Elderly Persons

45 older adults were tested twice per year for three years in a 9 (psychomotor) by 30 (health status, well-being) matrix of variables. That only 84 significant correlations were found suggests no relationship between psychomotor performance and health status.

Skill Analysis in Racquetball

To identify some of the tasks demands of racquetball using relative and absolute skill analysis techniques, a stepwise multiple regression was applied to scores on the Wingate Step Test, a measure of anaerobic power. Analysis indicated the test was a good predictor of racquetball skill. Time and motion analysis suggests racquetball is an anaerobic alactic sport.

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.