Break expectancy in duration discrimination.

Effects of break expectancy, observed previously in time production, were examined in 3 experiments using a discrimination paradigm. Participants classified a tone as being short or long. Location and duration of breaks in tone presentation were varied. Proportion of short responses increased as the break occurred later in the duration to be estimated in all experiments. With a higher number of break locations covering a wider range of location values, functions relating proportion of short responses to location were sigmoid and tended to flatten at extreme values of location. The authors conclude that attentional time-sharing elicited by break expectancy induces loss in accumulation of temporal information, but its effect on discrimination depends on the accumulation outcome relative to a decisional criterion.