The relation between gestures and stuttering in individuals with Down syndrome.

BACKGROUND: Evidence shows that neurotypical individuals who stutter use fewer gestures than those who do not stutter. Presently, no research exists about the interaction of stuttering and gestures in individuals with Down syndrome. METHOD: Twenty-nine individuals with Down syndrome (7-19 years) of whom 16 stuttered and 13 spoke fluently and 20 neurotypical children (3-10 years) of whom 8 stuttered and 12 spoke fluently participated in this study. In spontaneous speech transcriptions, stuttering events and gestures were coded. RESULTS: Comparisons of gesture frequency during stuttered and fluent speech inside the Down syndrome and neurotypical group show that the Down syndrome group uses significantly more gestures during stuttered than during fluent speech while no significant difference is seen in the neurotypical group. CONCLUSIONS: There is some preliminary evidence that individuals with Down syndrome try to compensate for their stuttering events, however, analyses on word level are necessary to confirm a successful compensation.

The effect of manual movements on stuttering in individuals with down syndrome.

PURPOSE: Stuttering may disrupt the speech of individuals with Down syndrome (DS), but standard stuttering therapies may be less adapted to these clients' needs. This study examined if their strength in gesture use can lead to the development of a new stuttering therapy. METHOD: Eighteen individuals with DS who stutter participated in an experimental task. During this task, they produced sentences in three different conditions: once without the ability to use gestures, once while moving the mouth of a hand puppet synchronous with their speech, and once while making beat gestures along their speech. Stuttering frequency was measured and compared between conditions while controlling for the effect of articulation rate. RESULTS: The experimental hand puppet and beat condition did not affect the stuttering frequency, but the covariate articulation rate did. An exploratory posthoc analysis showed that the articulation rate decreased during the experimental hand puppet and beat condition. Manual movements in the present task might only induce fluency through articulation rate reduction. However, analyses at individual level show significant interindividual variability. CONCLUSION: Individual analyses show that effect on stuttering frequency cannot be attributed entirely to articulation rate reduction and that beat gestures might still play a role. However, at this point, there is not enough direct evidence to implement beat gestures in current stuttering therapy.

Influence of gestures on the intelligibility and comprehensibility of utterances with stuttering events in individuals with Down syndrome.

INTRODUCTION: Individuals with Down syndrome (DS) often stutter, which can affect their speech intelligibility. Previous research has shown that manual signs can enhance speech intelligibility and comprehensibility. It remains unclear to what extent spontaneous hand gestures, such as iconic and beat gestures, may enhance intelligibility and/or comprehensibility during utterances with stuttering events. METHODS: Eleven individuals with DS who stutter provided video-recorded speech samples. From these samples, 60 utterances containing a stuttering event were selected. In half of them, the stuttering events were accompanied by gestures; in the other half, the stuttering events were not accompanied by gestures. The samples were shown to 250 assessors who were blind to the study's goals. Each sample was shown in three visibility conditions: 1) video-with-audio, 2) video-with-audio but with the speaker's mouth covered and 3) audio-only. The assessors rated speech intelligibility on a 7-point Likert scale and transcribed the speech sample. The effect of gesture production, gesture type and the visibility conditions on comprehensibility and intelligibility was examined with a hierarchical multiple linear regression. RESULTS: When a speaker had used a gesture during a stuttering event, the Likert scale score increased with 0.47 and the accuracy of transcription with 9.07%. There was no difference in effect between the different gesture types. Despite the effect from gesture use, there was no effect of the visibility conditions on the Likert scale or transcription score. CONCLUSIONS: Gestures positively affect intelligibility and comprehensibility of utterances with stuttering events in individuals with DS by altering the speech production. The possibility of beat gestures as a therapy method should be examined, with caution for the development of maladaptive behaviours.

An experiment on measuring awareness of stuttering in individuals with Down syndrome.

BACKGROUND: Awareness of stuttering is likely to depend upon the development of the metalinguistic skill to discriminate between fluent speech and stuttering and the ability to identify one's own speech as fluent or stuttered. Presently, little is known about these abilities in individuals with Down syndrome (DS). PURPOSE: This study investigates whether individuals with DS and typically developing (TD) children who stutter and who do not stutter differ in their ability to discriminate between fluent speech and stuttering. The second purpose of this study is to discover if this ability is correlated with their self-identification ability. METHOD: An experiment to investigate awareness with tasks for discrimination of stuttering and self-identification was developed. It was administered to 28 individuals (7-19 years) with DS, 17 of them stutter and 11 do not, and 20 TD children (3-10 years), 8 of them stutter and 12 do not. Skills to discriminate stuttering were compared between these groups and correlated with self-identification within these groups. The influence of stuttering severity and developmental/chronological age on their ability to discriminate was also investigated. RESULTS: The ability to discriminate does not differ significantly between the DS and TD group, but is highly influenced by developmental age. This ability correlates with self-identification but only for the TD individuals who speak fluently. CONCLUSION: The ability to discriminate matures around the age of 7 and conscious awareness may rely on this ability. Differences between the present findings and earlier studies suggest that differentiation in levels and types of awareness is warranted.

Key Word Signing Has Higher Iconicity Than Sign Language.

Purpose Key word signing (KWS) entails using manual signs to support the natural speech of individuals with normal hearing and who have communication difficulties. While manual signs from the local sign language may be used for this purpose, some KWS systems have opted for a distinct KWS lexicon. Distinct KWS lexicon typically aims for higher sign iconicity or recognizability to make the lexicon more accessible for individuals with intellectual disabilities. We sought to determine if, in the Belgian Dutch context, signs from such a distinct KWS lexicon (Spreken Met Ondersteuning van Gebaren [Speaking With Support of Signs; SMOG]) were indeed more iconic than their Flemish Sign Language (FSL) counterparts. Method Participants were 224 adults with typical development who had no signing experience. They rated the resemblance between a FSL sign and its meaning. Raw data on the iconicity of SMOG from a previous study were used. Translucency was statistically and qualitatively compared between the SMOG lexicon and their FSL counterparts. Results SMOG had an overall higher translucency than FSL and contained a higher number of iconic signs. Conclusion This finding may support the value of a separate sign lexicon over using sign language signs. Nevertheless, other aspects, such as wide availability and inclusion, need to be considered.