Overview:

Research in the Speech Disfluency Laboratory is generally aimed at acquiring a better understanding of the nature of those variables that may be responsible for the development or maintenance of childhood stuttering. The primary focus of our research is on spoken language production and fluency development. This research is based on the notion that the cause and/or initiation of instances of stuttering are related to the process of planning for speech production. The studies associated with this line of research are further described below.

Spoken Language Production and Childhood Stuttering:

Several research studies are currently being conducted in our laboratory to examine the interaction between linguistic processing abilities and fluency development in children who do and do not stutter between the ages of 3;0 and 5;11 (years; months).

Study #1: Lexical Retrieval Processes

The purpose of this research, which had beenfunded by a grant from the National Institute of Health (DC006805), is to determine whether disruptions in spoken language production are associated with developmental stuttering. The specific aims are to examine the speed and accuracy of processes associated with (a) lexical-phonological form retrieval (Project 1 ); (b) lexical conceptual retrieval (Project 2 ); and (c) conceptual influences on grammatical planning (Project 3 ). This research will shed light on how disruptions or inefficiencies in linguistic formulation processes—namely, those processes involved with lexical retrieval—may contribute to instances of stuttering in children.

Study #2: Linguistic Constraints on the Production of Speech Disfluencies

This research aims to examine the influence of phonological neighborhood variables (Project 1 ) and phonotactic probability (Project 2 ) on the production of speech disfluencies in both children and adults who stutter. These projects will provide insights into the role of lexical factors and phonological regularities on the moment of stuttering across the lifespan, and serve as a window into the underlying mechanisms presumed to be involved in the development of stuttering.

In general, findings from these studies will contribute to psycholinguistic theories of stuttering by delineating which linguistic processing components, if any, may be associated with the onset and development of childhood stuttering. In addition, findings will further our knowledge of the relationship between levels of speech-language formulation processes and the production of different types of speech disfluencies. Finally, and perhaps most importantly, it is hoped that these findings will set the stage for subsequent research to develop more effective, innovative approaches for managing childhood stuttering.