Associations between social anxiety, physiological reactivity, and speech disfluencies in autistic young adults and controls.

Introduction: The aim of this study was to examine possible associations of social anxiety (SA) and speaking-related physiological reactivity with the frequencies of a) total disfluencies, b) typical disfluencies, and c) stuttering-like disfluencies, as well as d) stuttering-severity in autistic young adults and controls.

Methods: Thirty-two autistic young adults and 35 controls participated in this study. Participants were presented with video clips (viewing condition) and were then asked to talk about the videos (narrating condition). SA was measured by the self-report Social Phobia and Anxiety Inventory (SPAI). Speaking-related physiological reactivity was measured by the electrodermal activity (EDA), an index of emotional arousal. The speech samples from the narrating condition were analyzed for type and frequency of speech disfluencies and used for determining the stuttering severity. SA and speaking-related physiological reactivity were compared between the groups. Correlation between SA, physiological reactivity, disfluency frequencies, and stuttering severity were tested separately for both groups.

Results: No between-group differences were found in the overall SA, yet differences were found in SPAI subscales of social interaction, group interaction, and avoidance, as well as in agoraphobia. Both groups had higher physiological arousal in narrating condition in comparison to the video viewing condition, yet there was no between-group difference in the reactivity. No associations were found between SPAI measures, physiological reactivity, disfluency frequencies, and stuttering severity in the autistic group. In the control group, a negative association was found between physiological reactivity and total and typical disfluency frequencies.

Conclusions: SA or speaking-related physiological reactivity were not associated with disfluency frequencies or stuttering severity in autistic persons. Negative association between physiological reactivity and disfluency frequencies found in the control group may indicate that the physiological arousal may impact the speech production process by reducing the overt disfluencies.