Dr. Peter joined the faculty in the Department of Speech and Hearing Science at Arizona State University as Assistant Professor in August 2014. She is Affiliate Assistant Professor in the UW's Department of Speech and Hearing Sciences, where she was Research Assistant Professor from 2012 to 2014. In October 2014, she was appointed Adjunct Assistant Professor at Saint Louis University, where she regularly teaches an introductory genetics course for speech-language pathology graduate students and practicing clinicians.
Speech Sound Disorders
With funding from the NIH, Dr. Peter is directing a study of the molecular genetics of speech sound disorder (SSD). Findings from the Peter Speech/Language Genetics lab include the observation that many children with childhood apraxia of speech and adults with such a history struggle specifically with tasks requiring rapid sequential processing; this deficit can be observed across many different task domains including reading and spelling. The Peter lab recently identified a candidate gene for childhood apraxia of speech (Peter, Matsushita, Oda & Raskind, 2014). A child with severe childhood apraxia of speech in the presence of dysarthric speech components was found to have a heterozygous de novo deletion of BCL11A on chromosome 2. BCL11A is situated within a known microdeletion region as well as a dyslexia candidate region. Our case is the first with only a single gene deleted and a phenotype characterized by deficits in motor planning and muscle tone, whereas the cases previously described had larger deletions and much more severe phenotypes including growth retardation, dysmorphic features, and brain anomalies.
Dr. Peter hypothesizes that reading disorders result from biologically based interferences with information transfer in the brain and that these interferences can be documented across many modalities and measures including EEG, ABR, MRI, and behavioral measures. She and her collaborators are currently collecting pilot data toward an extensive, multidisciplinary study of dyslexia where convergent evidence from the diverse measures will be evaluated for its genetic etiology. Findings from the Peter lab's study of childhood apraxia of speech are providing motivation to investigate sequential processing in dyslexia. Results from behavioral testing are consistent with the hypothesis that a deficit in rapid sequential processing underlies both childhood apraxia of speech and dyslexia. This may explain why many children with childhood apraxia of speech have difficulty learning to read and spell and, conversely, why individuals with dyslexia have difficulty with complex speech tasks.
As more genetic variants for speech sound disorder are discovered, the potential to identify infants at genetic risk increases. Whether or not this will lead to a new effort to design and provide preventative services to very young children remains to be seen. Dr. Peter and two colleagues are planning a trial intervention in infants at genetic risk for speech disorders due to known genetic variants causing a medical disorder. If this experiment results in improved outcomes in the speech of children who carry the disease variant, we will have evidence towards trying very early intervention in other cases.
In addition to teaching courses in childhood speech sound disorders, Dr. Peter has developed a line of courses on introductory genetics for students and professionals in the areas of speech-language pathology and audiology. Most recently, she developed a version of this course taught from an interprofessional platform that covers many clinical professions. As a member of the American Speech-Language-Hearing Association as well as the American Society of Human Genetics, she is engaged in collaborative educational outreach efforts.
Dr. Peter earned a Master of Science degree in Speech-Language Pathology at the University of Washington, where she also completed her Ph.D. degree in Speech and Hearing Sciences under the direction of Carol Stoel-Gammon, Ph.D. Her clinical expertise is in childhood speech and language disorders as well as in dyslexia. Dr. Peter completed three years of postdoctoral training under the mentorship of Wendy Raskind, M.D., Ph.D., in the Division of Medical Genetics at the University of Washington. Dr. Peter is the only clinical linguist ever to complete the Graduate Certificate in Statistical Genetics, sponsored by the Department of Biostatistics at the University of Washington.