CNL Lunch Talks

Nan Ratner & Rochelle Newman
Department of Hearing and Speech Sciences
University of Maryland

Thursday Oct 12th 2006, 12:30 PM, 3416 Marie Mount Hall

Factors that Affect Naming in Adults and Children Who Stutter

Purpose:

A large body of research now suggests that people who stutter demonstrate subtle linguistic processing deficits, and that it is these deficits, rather than motor dysfunction, that underlie the disorder. However, specification of the full scope and nature of these deficits is still uncertain. In particular, there is some suggestion whether or not the deficit arises at the syntactic, lexical or phonological level of encoding. The purpose of this study was to investigate whether lexical access in adults who stutter (AWS) differs from that in people who do not stutter. Specifically, we examined the role of three lexical factors on naming speed, accuracy and fluency: word frequency, neighborhood density, and neighborhood frequency. If stuttering results from an impairment in lexical access, these factors were hypothesized to differentially affect AWS' performance on a confrontation naming task.

Method:

Twenty-five AWS and 25 normally-fluent comparison speakers, matched for age and education, participated in a confrontation naming task designed to explore within-speaker performance on naming accuracy, speed and fluency based upon stimulus word frequency and neighborhood characteristics. Accuracy, fluency and reaction time (from acoustic waveform analysis) were computed. Results: In general, AWS demonstrated the same effects of lexical factors on their naming as did adults who do not stutter (AWDNS). However, accuracy of naming was reduced for AWS. Stuttering rate was influenced by word frequency but not other factors.

Conclusions:

Results suggest that AWS could have a fundamental deficit in lexical retrieval, but this deficit is unlikely to be at the level of the word's abstract phonological representation. This hypothesis is being explored in a follow-up study of children who stutter, and we will provide preliminary findings from this cohort.