Ashley de Marchena

Conversational gestures in autism spectrum disorders: Asynchrony but not decreased frequency

Conversational or “co‐speech” gestures play an important role in communication, facilitating turntaking, providing visuospatial information, clarifying subtleties of emphasis, and other pragmatic cues. Consistent with other pragmatic language deficits, individuals with autism spectrum disorders (ASD) are said to produce fewer conversational gestures, as specified in many diagnostic measures. Surprisingly, while research shows fewer deictic gestures in young children with ASD, there is a little empirical evidence addressing other forms of gesture. The discrepancy between clinical and empirical observations may reflect impairments unrelated to frequency, such as gesture quality or integration with speech. Adolescents with high‐functioning ASD (n=15), matched on age, gender, and IQ to 15 typically developing (TD) adolescents, completed a narrative task to assess the spontaneous production of speech and gesture. Naïve observers rated the stories for communicative quality. Overall, the ASD groups stories were rated as less clear and engaging. Although utterance and gesture rates were comparable, the ASD groups gestures were less closely synchronized with the co‐occurring speech, relative to control participants. This gesture–speech synchrony specifically impacted communicative quality across participants. Furthermore, while story ratings were associated with gesture count in TD adolescents, no such relationship was observed in adolescents with ASD, suggesting that gestures do not amplify communication in this population. Quality ratings were, however, correlated with ASD symptom severity scores, such that participants with fewer ASD symptoms were rated as telling higher quality stories. Implications of these findings are discussed in terms of communication and neuropsychological functioning in ASD.

Mutual exclusivity in autism spectrum disorders: Testing the pragmatic hypothesis

While there is ample evidence that children treat words as mutually exclusive, the cognitive basis of this bias is widely debated. We focus on the distinction between pragmatic and lexical constraints accounts. High-functioning children with autism spectrum disorders (ASD) offer a unique perspective on this debate, as they acquire substantial vocabularies despite impoverished social-pragmatic skills. We tested children and adolescents with ASD in a paradigm examining mutual exclusivity for words and facts. Words were interpreted contrastively more often than facts. Word performance was associated with vocabulary size; fact performance was associated with social-communication skills. Thus mutual exclusivity does not appear to be driven by pragmatics, suggesting that it is either a lexical constraint or a reflection of domain-general learning processes.

The art of common ground: emergence of a complex pragmatic language skill in adolescents with autism spectrum disorders.

Deficits in pragmatic language are central to autism spectrum disorder (ASD). Here we investigate common ground, a pragmatic language skill in which speakers adjust the contents of their speech based on their interlocutors perceived knowledge, in adolescents with ASD and typical development (TD), using an experimental narrative paradigm. Consistent with prior research, TD participants produced shorter narrations when they shared knowledge with an interlocutor, an effect not observed at the group level in ASD. This effect was unrelated to general skills such as IQ or receptive vocabulary. In ASD, the effect was correlated with age and symptom severity: older and less severely affected participants did shorten their narratives. Several metrics (including explicit references to common ground, speech disfluencies, and communicative quality ratings) suggested that, although adolescents with ASD did not show implicit reductions in their narrative length, they were aware of common ground, and communicated differently in its presence.

Brief Report: Generalization Weaknesses in Verbally Fluent Children and Adolescents with Autism Spectrum Disorder

Abstract Individuals with autism spectrum disorder (ASD) have difficulty generalizing—i.e., relating new stimuli to past experiences. Few experimental studies have addressed this weakness, despite its impact on intervention effects. In a reanalysis of data (de Marchena et al. Cognition 119(1):96–113, 2011), we tested a novel form of generalization—the ability to transfer a strategy used in one context to a similar context—in verbally fluent youth with ASD and matched typically developing controls. Participants with ASD were subtly less likely to learn from experience; their generalizations were less consistent. Generalization in ASD correlated with receptive vocabulary but not age, suggesting a link to language development. A richer understanding of how to promote generalization in ASD will advance both theory and practice.

“Frank” presentations as a novel research construct and element of diagnostic decision‐making in autism spectrum disorder

Many individuals with ASD have a distinctive behavioral presentation that is recognizable within moments, a phenomenon we call “frank” ASD. This phenomenon has been discussed informally for decades, perhaps as “classic” ASD; however, there is no unitary “classic” presentation, and classic autism does not seem to correspond to level of functioning. Thus, neither “frank” nor “classic” autism has been delineated or studied as a research construct. To initiate the empirical study of frank ASD, we surveyed 151 clinicians, from a range of disciplines that diagnose ASD, about this phenomenon. Respondents completed a 13‐item questionnaire about frank ASD, which was analyzed using a mixed‐methods approach. Ninety‐seven percentage of respondents were familiar with the phenomenon. Respondents estimated that 40% of the ASD population has a frank presentation. Respondents reported the most highly specific behaviors associated with frank presentations were a general sense of impaired reciprocity, quality of eye contact, atypical vocal prosody, presence of motor mannerisms, and atypical gait or posture. In general, respondents reported detecting frank features rapidly, with the majority forming their impressions within the first ten minutes of interaction or observation. Although unstudied empirically, “frank” presentations of ASD are familiar to diagnosing clinicians, and appear to be based on behaviors both central to ASD diagnostic criteria (e.g., impaired reciprocity), and absent from diagnostic criteria (e.g., atypical gait or posture). We discuss these findings within the context of diagnostic decision‐making and behavioral phenotyping of ASD. Autism Res 2016,.

Motor signatures in Autism Spectrum Disorder: The importance of variability

In a recent study, Wang et al. (J Neurophysiol 113: 1989-2001, 2015) used a precision grip force control task to unveil the contribution of feedforward and feedback mechanisms to sensorimotor dysfunction in autism spectrum disorder (ASD). Impairment of both motor control mechanisms was observed, along with significant variability in the motor response. In this Neuro Forum article we discuss these findings within the conceptual framework of the grasping circuit and within the broader context of clinical and research applications based on motor behavior.