Time estimation by adults who stutter.
In view of the fact that stuttering involves time pressure in communicative contexts, the aim of this investigation was to study the effect of stuttering on time estimation. Two matching groups of 47 adults each, one consisting of stutterers and the other of fluent speakers, estimated the duration of four verbal tasks-two that involved speaking and two that did not. Two methods of time estimation were used: production and reproduction. In production, participants were required to perform a task, terminating it when they felt that the specified interval had elapsed. In reproduction, participants were asked to estimate the duration of a task immediately after being stopped by the experimenter. The results reveal that the differences in time estimation between adults who stutter and fluent speakers were task dependent, with the stutterers estimating time less accurately on oral verbal tasks. The conversation task in particular highlighted the inaccuracy of their time estimation. Furthermore, severe stutterers estimated time less accurately than mild stutterers. The greatest inaccuracy was displayed by severe stutterers when estimating the time of an oral task by the production method. The results are discussed in terms of cognitive models based on attention to time, method measurement, and mental workload. Clinical implications are also suggested.