Publications

Purpose:  As  evidenced  by  perceptual  learning  studies  involving  adult  listeners and  speakers  with  dysarthria,  adaptation  to  dysarthric  speech  is  driven  by  signal  predictability  (speaker  property)  and  a  flexible  speech  perception  system (listener  property).  Here,  we  extend  adaptation  investigations  to  adolescent  pop-ulations  and  examine  whether  adult  and  adolescent  listeners  can  learn  to  better understand  an  adolescent  speaker  with  dysarthria. 

Method: Classified  by  developmental  stage,  adult  (n  =  42)  and  adolescent  (n  = 40)  listeners  completed  a  three-phase  perceptual  learning  protocol  (pretest, familiarization,  and  posttest).  During  pretest  and  posttest,  all  listeners  tran-scribed  speech  produced  by  a  13-year-old  adolescent  with  spastic  dysarthria associated  with  cerebral  palsy.  During  familiarization,  half  of  the  adult  and  ado-lescent  listeners  engaged  in  structured  familiarization  (audio  and  lexical  feed-back)  with  the  speech  of  the  adolescent  speaker  with  dysarthria;  and  the  other half,  with  the  speech  of  a  neurotypical  adolescent  speaker  (control). 

Results: Intelligibility  scores  increased  from  pretest  to  posttest  for  all  listeners. However,  listeners  who  received  dysarthria  familiarization  achieved  greater  intelligibility  improvements  than  those  who  received  control  familiarization.  Further-more,  there  was  a  significant  effect  of  developmental  stage,  where  the  adults achieved  greater  intelligibility  improvements  relative  to  the  adolescents. 

Conclusions: This  study  provides  the  first  tranche  of  evidence  that  adolescent dysarthric  speech  is  learnable—a  finding  that  holds  even  for  adolescent  listeners  whose  speech  perception  systems  are  not  yet  fully  developed.  Given  the formative  role  that  social  interactions  play  during  adolescence,  these  findings  of improved  intelligibility  afford  important  clinical  implications.

Purpose: Defined as the similarity of speech behaviors between interlocutors, speech entrainment plays an important role in successful adult conversations. According to theoretical models of entrainment and research on motoric, cognitive, and social developmental milestones, the ability to entrain should develop throughout adolescence. However, little is known about the specific developmental trajectory or the role of speech entrainment in conversational outcomes of this age group. The purpose of this study is to characterize speech entrainment patterns in the conversations of neurotypical early adolescents.

Method: This study utilized a corpus of 96 task-based conversations between adolescents between the ages of 9 and 14 years and a comparison corpus of 32 task-based conversations between adults. For each conversational turn, two speech entrainment scores were calculated for 429 acoustic features across rhythmic, articulatory, and phonatory dimensions. Predictive modeling was used to evaluate the degree of entrainment and relationship between entrainment and two metrics of conversational success.

Results: Speech entrainment increased throughout early adolescence but did not reach the level exhibited in conversations between adults. Additionally, speech entrainment was predictive of both conversational quality and conversational efficiency. Furthermore, models that included all acoustic features and both entrainment types performed better than models that only included individual acoustic feature sets or one type of entrainment.

Conclusions: Our findings show that speech entrainment skills are largely developed during early adolescence with continued development possibly occurring across later adolescence. Additionally, results highlight the role of speech entrainment in successful conversation in this population, suggesting the import of continued exploration of this phenomenon in both neurotypical and neurodivergent adolescents. We also provide evidence of the value of using holistic measures that capture the multidimensionality of speech entrainment and provide a validated methodology for investigating entrainment across multiple acoustic features and entrainment types.

Social communication and interaction (SC/I) skill quality may be influenced by cultural values, norms, and expectations. Because difficulties in SC/I is a core criterion for identifying autism and is a frequent construct of interest in autism research, a measure designed to capture cross-cultural differences in the perspectives of SC/I skills is warranted. To address this need we developed and validated the Social Communication and Interaction Perceptions Scale (SCIPS), a caregiver report measure for children ages 6–18 years, that measures both frequency and perceived importance of various SC/I skills. Results from 401 diverse caregiver participants showed that for both domains (i.e., Frequency and Importance) the SCIPS has good reliability (α = 0.88-0.95) and two factors that examine basic and advanced aspects of SC/I skills. Findings support the use of the SCIPS as a measure of caregiver perspectives of SC/I skills in clinical and research contexts.

Conversational entrainment, also known as alignment, accommodation, convergence, and coordination, is broadly defined as similarity of communicative behavior between interlocutors. Within current literature, specific terminology, definitions, and measurement approaches are wide-ranging and highly variable. As new ways of measuring and quantifying entrainment are developed and research in this area continues to expand, consistent terminology and a means of organizing entrainment research is critical, affording cohesion and assimilation of knowledge. While systems for categorizing entrainment do exist, these efforts are not entirely comprehensive in that specific measurement approaches often used within entrainment literature cannot be categorized under existing frameworks. The purpose of this review article is twofold: First, we propose an expanded version of an earlier framework which allows for the categorization of all measures of entrainment of speech behaviors and includes refinements, additions, and explanations aimed at improving its clarity and accessibility. Second, we present an extensive literature review, demonstrating how current literature fits into the given framework. We conclude with a discussion of how the proposed entrainment framework presented herein can be used to unify efforts in entrainment research.

Purpose: Acoustic–prosodic entrainment, defined as the tendency for individuals to modify their speech behaviors to more closely align with the behaviors of their conversation partner, plays an important role in successful interaction. From a mechanistic perspective, acoustic–prosodic entrainment is, by its very nature, a rhythmic activity. Accordingly, it is highly plausible that an individual's rhythm perception abilities play a role in their ability to successfully entrain. Here, we examine the impact of rhythm perception in speaking rate entrainment and subsequent conversational quality.

Method: A round-robin paradigm was used to collect 90 dialogues from neurotypical adults. Additional assessments determined participants' rhythm perception abilities, social competence, and partner familiarity (i.e., whether the conversation partners knew each other prior to the interaction. Mediation analysis was used to examine the relationships between rhythm perception scores, speaking rate entrainment (using a measure of static local synchrony), and a measure of conversational success (i.e., conversational quality) based on third-party listener observations. Findings were compared to the same analysis with three additional predictive factors: participant gender, partner familiarity, and social competence.

Results: Results revealed a relationship between rhythm perception and speaking rate entrainment. In unfamiliar conversation partners, there was a relationship between speaking rate entrainment and conversational quality. The relationships between entrainment and each of the three additional factors (i.e., gender, partner familiarity, and social competence) were nonsignificant.

Conclusions: In unfamiliar conversation partners, better rhythm perception abilities were indicative of increased conversational quality mediated by higher levels of speaking rate entrainment. These results support theoretical postulations specifying rhythm perception abilities as a component of acoustic–prosodic entrainment, which, in turn, facilitates conversational success. Knowledge of this relationship contributes to the development of a causal framework for considering a mechanism by which rhythm perception deficits in clinical populations may impact conversational success.

Purpose: According to the speech attunement framework, autistic individuals lack the ability and/or motivation to “tune up” their speech to the same level of precision as their neurotypical peers. However, previous studies exploring the articulatory patterns of autistic individuals have yielded disparate findings. One reason contrasting conclusions exist may be because studies have relied on perceptual measures of articulation. Here, we use an objective acoustic measure of articulatory precision to explore the articulatory patterns of autistic children and adults. 

Method: This was a retrospective analysis of an existing corpus of 900 recorded speech samples taken from 30 adult and 30 child participants across two different population groups: autistic individuals (autism spectrum disorder [ASD] group) and neurotypical individuals (neurotypical [NT] group). Articulatory precision scores were calculated using an automated metric that compares observed acoustics to the expected acoustics for each phoneme production. Linear mixed-effects models were used to compare the articulatory precision scores across population group (i.e., ASD group vs. NT group) and to see if these differences were moderated by age group (i.e., children vs. adult). 

Results: The speech of autistic individuals was characterized by reduced articulatory precision relative to their neurotypical peers. This pattern was not significantly moderated by age, indicating it occurred in both the children and adult groups. 

Conclusions: Our preliminary findings indicate that imprecise articulation may be a characteristic of the speech of autistic individuals in both childhood and adulthood. These findings are in line with predictions posited by the speech attunement framework. Given the current lack of speech markers for this clinical population and the importance of speech quality in the social integration of autistic individuals, our results advance articulatory precision as a viable and important target for future research

Purpose: We proposed and tested a causal instantiation of the World Health Organization’s International Classification of Functioning, Disability and Health (ICF) framework, linking acoustics, intelligibility, and communicative participation in the context of dysarthria. 

Method: Speech samples and communicative participation scores were collected from individuals with dysarthria (n = 32). Speech was analyzed for two acoustic metrics (i.e., articulatory precision and speech rate), and an objective measure of intelligibility was generated from listener transcripts. Mediation analysis was used to evaluate pathways of effect between acoustics, intelligibility, and communicative participation. 

Results: We observed a strong relationship between articulatory precision and intelligibility and a moderate relationship between intelligibility and communicative participation. Collectively, data supported a significant relationship between articulatory precision and communicative participation, which was almost entirely mediated through intelligibility. These relationships were not significant when speech rate was specified as the acoustic variable of interest. 

Conclusion: The statistical corroboration of our causal instantiation of the ICF framework with articulatory acoustics affords important support toward the development of a comprehensive causal framework to understand and, ultimately, address restricted communicative participation in dysarthria.

Purpose: Coordination of communicative behavior supports shared understanding in conversation. The current study brings together analysis of two speech coordination strategies, entrainment and compensation of articulation, in a preliminary investigation into whether strategy organization is shaped by a challenging communicative context—conversing with a person who has a communication disorder. 

Method: As an initial clinical test case, an automated measure of articulatory precision was analyzed in a corpus of spoken dialogue, where a confederate conversed with participants with traumatic brain injury (n = 28) and participants with no brain injury (n = 48). 

Results: Overall, the confederate engaged in significant entrainment and high compensation (hyperarticulation) in conversations with participants with traumatic brain injury relative to significant entrainment and low compensation (hypoarticulation) in conversations with participants with no brain injury. Furthermore, the confederate’s articulatory precision changed over the course of the conversations. 

Conclusions: Findings suggest that the organization of conversational coordination is sensitive to context, supporting synergistic models of spoken dialogue. While corpus limitations are acknowledged, these initial results point to differences in the way in which speech strategies are realized in challenging communicative contexts, highlighting a viable and important target for investigation with clinical populations. A framework for investigating speech coordination strategies in tandem and ideas for advancing this line of inquiry serve as key contributions of this work.

Purpose: Conversational entrainment describes the tendency for individuals to alter their communicative behaviors to more closely align with those of their conversation partner. This communication phenomenon has been widely studied, and thus, the methodologies used to examine it are diverse. Here, we summarize key differences in research design and present a test case to examine the effect of methodology on entrainment outcomes.

Method: Sixty neurotypical adults were randomly assigned to experimental groups formed by a 2 × 2 factorial combination of two independent variables: stimuli organization (blocked vs. random presentation) and stimuli modality (auditoryonly vs. audiovisual stimuli). Individuals participated in a quasiconversational design in which the speech of a virtual interlocutor was manipulated to produce fast and slow speech rate conditions. 

Results: There was a significant effect of stimuli organization on entrainment outcomes. Individuals in the blocked, but not the random, groups altered their speech rate to align with the speech rate of the virtual interlocutor. There were no effect of stimuli modality and no interaction between modality and organization on entrainment outcomes. 

Conclusion: Findings highlight the importance of methodological decisions on entrainment outcomes. This underscores the need for more comprehensive research regarding entrainment methodology.

Purpose: Conversational entrainment is the tendency for individuals to modify their behavior to more closely converge with the behavior of their communication partner and is an important aspect of successful interaction. Evidence of entrainment in adults is robust, yet research regarding its development in children is sparse. Here, we investigate the emergence of entrainment skills in typically developing children. 

Method: Data were collected from a total of 50 typically developing children between the ages of 5 and 14 years. Children participated in a quasiconversational paradigm with a virtual interlocutor. Speech rate of the interlocutor was digitally manipulated to produce fast and slow speech rate conditions. 

Results: Data from the fast and slow conditions were compared using linear mixed models. Results indicated that children, regardless of age, did not alter their speech to match the rate of the virtual interlocutor. 

Conclusions: Findings suggest that entrainment in children may not be as robust as entrainment in adults and therefore not adequately captured with the current experimental paradigm. Modifications to the current paradigm will help identify a methodology sufficiently sensitive to capture the speech alignment phenomenon in children and provide much needed information regarding the typical stages of entrainment development.

Purpose: Conversational entrainment is the tendency for individuals to modify their behavior to more closely converge with the behavior of their communication partner and is an important aspect of successful interaction. Evidence of entrainment in adults is robust, yet research regarding its development in children is sparse. Here, we investigate the emergence of entrainment skills in typically developing children. 

Method: Data were collected from a total of 50 typically developing children between the ages of 5 and 14 years. Children participated in a quasiconversational paradigm with a virtual interlocutor. Speech rate of the interlocutor was digitally manipulated to produce fast and slow speech rate conditions. 

Results: Data from the fast and slow conditions were compared using linear mixed models. Results indicated that children, regardless of age, did not alter their speech to match the rate of the virtual interlocutor. 

Conclusions: Findings suggest that entrainment in children may not be as robust as entrainment in adults and therefore not adequately captured with the current experimental paradigm. Modifications to the current paradigm will help identify a methodology sufficiently sensitive to capture the speech alignment phenomenon in children and provide much needed information regarding the typical stages of entrainment development.