Inge-Marie Eigsti - US grants

This dissertation examines how grammatical knowledge and referential salience guide early world learning in autism, a developmental disability characterized by significant language deficits. The process of word learning requires a child to match co-occurrences of words of parts of words (morphemes) and their meanings. This matching demands the integration of multiple, probabilistic cues from the linguistic, social, and real-world contexts, and thus may depend on working memory. Paradoxically, the limited short-term verbal memory characteristic of typically-developing children may improve this analysis of co- occurrences. Their limited memory for verbal strings may focus attention on smaller elements, which in language are the most important meaning- bearing units for grammatical information. In contrast, a pattern of efficient verbal short-term memory and limited working memory could impede rule-learning, leading to language delays. This pattern is thought to characterize children with autism, and thus may help explain their language deficits. The present study examines early language in autism using a word-learning task that varies both grammatical and referential cues to a novel word. This task, which examine sub-categorization into count and mass non classes, is highly relevant to word learning in normal development. The influence of social and non-social referential cues is also compared. Working and short-term phonological memory are tested in order to assess whether the hypothesized pattern of memory deficits is correlated with performance on the lexical task. Participants will be 20 children with autism, 20 verbal and chronological age-matched children with Down syndrome, and 20 verbal mental age-matched normal controls. Results will inform out understanding of language development in autism and thus have important implications for intervention. Results will also heighten our understanding of the roles that working and short-term phonological memory play in language development.

Some individuals meet gold-standard clinical criteria for ASD prior to age 5 but end up later in development with no symptoms of ASD, and IQ and adaptive skills in the average range. This study evaluates this ?optimal outcome? (OO) in two groups: (1) those who participated in our OO research study as teens, now young adults, allowing us to evaluate how they navigate the difficult transition into independence and young adulthood; and (2) those who were diagnosed by us with ASD at age two and re-evaluated at age four, now in their teens, allowing us to identify which of this cohort has achieved optimal outcome, and thus to identify early predictors of OO. Both cohorts are compared to age-, gender-, and NVIQ-matched individuals with current ASD and with typical development (TD). We hypothesize that the young adults with OO will experience mild delays in adult milestones such as finishing higher education and obtaining competitive employment, along with greater anxiety, especially simple phobias, and ADHD symptoms. We also hypothesize that early childhood predictors of OO will be milder social impairment, higher adaptive skills in social, communication, and motor domains, and fewer repetitive behaviors. We employ fMRI in the second cohort (n=50 per study group, total n=150) to measure the functional connectivity networks that are involved in social and language tasks, and that are observed during resting state, to investigate how neural mechanisms relate to the dramatic symptom change observed in OO. Drawing on prior imaging research, we hypothesize that, compared to both ASD and TD, the OO group will show compensatory (atypical) connectivity of extra-modular prefrontal cognitive control networks and right hemisphere homologues of left-hemisphere language regions during language and social processing and during resting state.

PROJECT SUMMARY/ABSTRACT Disordered communication can come about as a consequence of hearing loss, as a result of developmental disorders such as autism, dyslexia, or developmental language disorder (DLD), or as a function of acquired disorders such as aphasia or traumatic brain injury (TBI). In order to make progress in assessment and treatment of communication disorders, the next generation of communication scientists needs to not only understand the underlying neural bases of these disorders, but also how to bring research from the laboratory to the clinic. The current program, Training in the Cognitive Neuroscience of Communication, will recruit a total of ten predoctoral trainees and five postdoctoral trainees, each serving a two-year traineeship, and equip them with specific skills and competencies that are needed for progress in understanding these disorders. Trainees from Psychology and Speech, Language, and Hearing Sciences will receive targeted instruction in cognitive neuroscience, with a special emphasis on neuroimaging methods, and will learn to apply those skills in trainee- led, mentored research projects. Further, training will emphasize the application of basic research, and trainees will interact not only with scientists who are experts in communication disorders, but also community stakeholders, including those that experience conditions such as aphasia, dyslexia, and autism. Other value- added activities will include a professional development seminar, January-term ?crash-courses? emphasizing specialized skills, and external workshops to support advanced methods training. Our mentor team, drawn from Speech, Language, and Hearing Sciences, and three different degree programs in Psychology (Clinical, Developmental, Perception-Action-Cognition), has substantial expertise in a variety of imaging methods (e.g. fMRI, fNIRS, TMS/tDCS, EEG/ERP) and has conducted impactful research on range of communication disorders (e.g. aphasia, hearing loss, dyslexia, developmental language disorder, autism). The team has a strong track record of impactful research on typical and atypical communication, and of mentoring productive scientist trainees at the predoctoral and postdoctoral levels. This training program will produce a cohort of scholars who are poised to make significant progress in the study of communication. !