Contrasting effects of interference and of breaks in interval timing

When a break is introduced during an interval to be timed, the interval is perceived shorter as break location is delayed. This is interpreted as a result of attention sharing between timing and monitoring the source of the break signal. Similar effects and interpretations are found in another context involving interfering tasks. Such tasks are assumed to induce transient interruptions in timing, comparable to those obtained with breaks. Break and interference conditions were contrasted in a temporal reproduction procedure with identical stimuli. Both conditions induced temporal underestimation and similar location effects. Similar trends occurred in a control condition where no processing of the interfering signal was required. The data suggest that expectancy, intentional processing, and automatic attraction of attention shorten temporal estimates.     

Conservation learning and the differential impact of visual information available during and after modeling

In order to investigate the nature of the processes that promote the observational learning of conservation, nonconservers were allowed or not visual access to the conservation stimuli while an adult model verbalized the conservation rule. In addition, after each demonstration the subjects were submitted to one of four conditions. The first three conditions involved a short pause during which the observers respectively kept seeing the stimuli, had to visualize them mentally, and had to visualize mentally some irrelevant stimuli; no interruption occurred in the fourth condition. As predicted, the withdrawal of visual information at the time of rule exemplification was accompanied with lower learning scores. However, equivalent acquisition was found with respect to each of the conditions in which the subjects were invited to examine specific stimuli after rule modeling. Altogether these data were discussed in terms of the greater and lesser extent to which the conditions permitted the children, during the observational training, to practice covertly the modeled solution.     

To count or not to count: the effect of instructions on expecting a break in timing

When a break is expected during a time interval production, longer intervals are produced as the break occurs later during the interval. This effect of break location was interpreted as a result of distraction related to break expectancy in previous studies. In the present study, the influence of target duration and of instructions about chronometric counting strategies on the break location effect was examined. Using a strategy such as chronometric counting enhances the reliability of temporal processing, typically in terms of reduced variability, and could influence how timing is affected by break expectancy, especially when relatively long target durations are used. In two experiments, results show that time productions lengthened with increasing value of break location at various target durations and that variability was greater in the no-counting than in the counting instruction condition. More important, the break location effect was stronger in the no-counting than in the counting instruction condition. We conclude that chronometric counting orients attention toward timing processes, making them less likely to be disrupted by concurrent nontemporal processes.