ملاحظات روش در اندازه گیری زمان واکنش در افرادی که لکنت زبان دارند

This research note describes potential trends in the reaction time (RT) performance of persons who stutter (PWS). The main purpose of this note is to describe these trends to researchers, encourage further research in this area, and alert researchers to possible concerns about the interaction of certain reaction time research procedures and characteristics of PWS. Post hoc analyses and a brief review of selected studies comparing the RT of PWS and PNS revealed three potential trends: (a) PWS show different practice effects relative to fluent speakers (PNS) on RT measures, (b) practice effect differences between PWS and PNS in RT are dependent upon task complexity, and (c) variable foreperiod intervals (VFI) may differentially affect the RT of PWS and PNS. A 15-item guide is included to aid both clinicians and researchers in the critical review of RT studies and to facilitate planning of future studies incorporating RT as an indicator of potential differences between PWS and PNS. Educational objectives: As a result of this activity the participant will be able to: (1) Define practice effects as they relate to skill learning (2) Summarize the reviewed literature concerning the performance of PWS on motorically simple and complex RT tasks over practice, and (3) Explain the implications for statistical analysis of a significant relationship between variable foreperiod and RT measures for PWS.

1.1. Primary objective The primary objective of this research note is to describe trends in reviewed reaction time studies suggesting that (a) persons who stutter (PWS) show different practice effects relative to fluent speakers (PNS) on reaction time (RT) measures, (b) practice effect differences between PWS and PNS in RT are task dependent, and (c) variable foreperiod intervals (VFI) may differentially affect the RT of PWS and PNS. The main purpose of this note is educational and specific to methodology, rather than attempting to review and synthesize the findings of all the RT studies in the area of stuttering. This research note serves the purpose of alerting researchers that these trends may affect the results of reaction time studies and to encourage replication studies in this area. A review of several recent RT studies presented in the Journal of Fluency Disorders suggested important trends in those studies which compared the RT of PWS and PNS deserving further investigation. Therefore a selection of the RT studies reviewed in Bloodstein's most recent “Handbook on Stuttering” (2008; pp. 170–173) was taken to further investigate the existence of these trends. Care was taken to ensure studies from several research groups and several time periods as well as studies both confirming and refuting the existence of the trends proposed by this paper were included. Studies found in the Journal of Fluency Disorders or reviewed by the Handbook were selected because they were conducted in the last 20–30 years, were basically methodologically sound, and were published in accredited, peer-review journals. Studies were also selected based on their accessibility to North American clinicians and researchers. Only those studies published in widely read and widely available journals were included (such as were available online, at the University of Toronto library and the University of McGill library).

The main purpose of this note was to alert researchers to potential trends in the literature comparing the RT of PWS and PNS and well as possible concerns regarding the interaction of certain RT research procedures and characteristics of PWS. Trends described herein were that (a) PWS showed different practice effects relative to PNS on RT measures, (b) practice effect differences between PWS and PNS in RT appeared to be dependent upon task response complexity, and (c) VFI effects may differentially influence the RT of PWS and PNS. This research note had a strictly methodological focus and precluded discussion of the many interesting questions raised during the post hoc analyses and review. For example, what do these findings mean in terms of a theory of stuttering and its underlying causes? Why are PWS more susceptible to variable VFI? Would similar practice effect differences between PWS and PNS also be seen on other performance measures such as accuracy, disfluencies, and movement durations? The information presented within this note provides fodder for future research and review articles and sufficient evidence to justify further investigation in this area.