I. Genetics of Speech Sound Disorders and Neurological Correlates
This study examines the neuronal networks supporting the planning and/or programming of spatiotemporal parameters of movement for speech sound production. The project uses functional MRI techniques to examine the premotor, motor cortex, subcortical and cerebellar components of the basic speech production network in children with speech sound disorders. The neuroimaging measures are correlated with behavioral measures. The findings of this study will increase the understanding of neurogenic source of the deficit in planning and/or programming of spatiotemporal parameters of movement for speech sound production in children with speech disorders. Such results are expected to have an important positive impact by advancing the development of more focused intervention strategies for children with speech sound disorders, thus reducing associated learning disabilities into the school-age years.
II. Symptoms of Autistic Disorder in Prader-Willi Syndrome.
The goal of this study is to examine social and communication problems in individuals with PWS in comparison to those with an autism spectrum disorder. Preliminary findings and genetic research indicates people with PWS who have uniparental disomy (UPD) genetic status may be more likely to show symptoms of autism than those with paternal deletion subtype. We aim to use the gold standard standardized measures to assess symptoms of autism to investigate the potential link to Prader-Willi syndrome. In addition, speech and language evaluations will be conducted and social-perceptual problems (such as difficulty recognizing faces) will be compared to individuals with autism spectrum disorders.This research is supported by a grant from the Prader-Willi Syndrome Association (PWSA-USA).
III. Genetic Causes of Developmental Speech Sound Disorder in Families
Communication Disorders are common in children, may persist into adulthood, and are recognized as a possible cause of pervasive and lifelong disabilities. Three communication disorders, speech sound disorder, reading disorder and language impairment are common in children and sometimes impact academic achievement. Dr. Iyengar’s project seeks to discover the common genetic bases underlying speech, language and reading disorders, to identify subtypes of speech sound disorders, and to develop new statistical methods for analyzing these and other developmental disorders.