Could linguistic and cognitive factors, degree of autistic traits and sex predict speech disfluencies in autistic young adults and controls?

This study aimed to evaluate the effect of linguistic complexity and individual background variables (i.e. linguistic and cognitive abilities, degree of autistic traits, and sex) on speech disfluencies in autistic young adults and controls. Thirty-two 19- to 33-year-old autistic adults and 35 controls participated in this study. The frequency of disfluencies and stuttering severity were evaluated based on a narrative speech task. Linguistic complexity was assessed by evaluating the syntactic structures of the narratives. Cognitive and linguistic abilities were assessed using the General Ability Index (GAI), Verbal Comprehension Index (VCI) and Perceptual Reasoning Index (PRI) from the Wechsler Adult Intelligence Scale IV. Autistic traits were measured using the Autism Spectrum Quotient (AQ). Multiple-linear regression analyses (syntactic complexity, GAI, AQ, sex, and group status as predictors) showed that (a) syntactic complexity predicted total and stuttering-like disfluencies and stuttering severity, (b) GAI predicted typical disfluencies, and (c) sex predicted total, typical, and stuttering-like disfluencies. Additional correlation analyses revealed negative association between PRI and disfluencies in the control group but not in the autistic group. No connection was found between AQ and disfluencies. It seems that while some connections between disfluencies and individual cognitive features were found, some of the possible contributing factors for greater speech disfluency might differ between autistic and typical speakers.

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.

A Comprehensive Analysis of Speech Disfluencies in Autistic Young Adults and Control Young Adults: Group Differences in Typical, Stuttering-Like, and Atypical Disfluencies.

PURPOSE: The purpose of this study was to examine the nature of speech disfluencies in autistic young adults and controls by using a wide-range disfluency classification of typical disfluencies (TD; i.e., filled pauses, revisions, abandoned utterances, and multisyllable word and phrase repetitions), stuttering-like disfluencies (SLD; i.e., sound and syllable repetitions, monosyllable word repetitions, prolongations, blocks, and broken words), and atypical disfluencies (AD; i.e., word-final prolongations and repetitions and atypical insertions). METHOD: Thirty-two autistic young adults and 35 controls completed a narrative telling task based on socially complex events. Frequencies of total disfluencies, TD, SLD, AD and stuttering severity were compared between groups. RESULTS: The overall frequency of disfluencies was significantly higher in the autistic group and significant between-group differences were found for all disfluency categories. The autistic group produced significantly more revisions, filled pauses, and abandoned utterances, and each subtype of SLD and AD than the control group. In total, approximately every fourth autistic participants scored at least a very mild severity of stuttering, and every fifth produced more than three SLD per 100 syllables. CONCLUSIONS: Disfluent speech can be challenging for effective communication. This study revealed that the speech of autistic young adults was highly more disfluent than that of the controls. The findings provide information on speech disfluency characteristics in autistic young adults and highlight the importance of evaluating speech disfluency with a wide-range disfluency classification in autistic persons in order to understand their role in overall communication. The results of this study offer tools for SLPs to evaluate and understand the nature of disfluencies in autistic persons.