Gallaudet’s First PH.D. in Educational Neuroscience (PEN) Doctoral Student Defends Dissertation

June 6, 2017

Adam Stone successfully defended his dissertation on Monday, June 5 (Dr. Laura-Ann Petitto, advisor). Adam will be the PEN program’s first doctoral graduate.

Adam Michael Stone, Dr. Laura-Ann Petitto's doctoral student in Gallaudet University’s Ph.D. in Educational Neuroscience (PEN) program and a graduate research assistant in Dr. Petitto’s Brain & Language Laboratory for Neuroimaging (BL2), successfully defended his dissertation on “Neural systems for infant sensitivity to phonological rhythmic-temporal patterning” on Monday, June 5, 2017.

Dr. Gaurav Mathur, Dean of Gallaudet University’s Graduate School, said of the researcher’s work:

"Mr. Stone’s study is rooted in the discipline of Educational Neuroscience and strives to exemplify this discipline’s commitment to basic cognitive neuroscience research and its principled translation for the benefit of society.

This cognitive neuroscience study explores the neural mechanisms that make possible an infants' ability to find salient phonetic-syllabic units in the language stream around them, and whether this capacity derives from a nascent peaked sensitivity to maximally contrasting rhythmic-temporal patterning corresponding to syllabic rate. 

The study also tests the hypothesis that the superior temporal gyrus (STG) and left inferior frontal cortex (LIFC) are the predominant brain sites containing the neural substrates that mediate this sensitivity. 

Twenty-nine (29) infants aged 6 to 8 months (six exposed to a signed language) participated in this fNIRS neuroimaging study.  Analyses of the data indicated that infants demonstrated sensitivity to rhythmic-temporal patterning in visual signed language, discriminating between faster (3.0 Hz) and slower (0.5 and 1.5 Hz) frequencies.

Importantly, this sensitivity appeared to be nascent and not contingent on language experience, in line with predictions from the peaked sensitivity account. Investigating how infants discover the finite set of phonetic units in their native language helps identify an important component in the multi-componential processes that underlie human language acquisition.

The study helps identify the early-life language patterns that all infants must encounter and lays bare the foundations of phonological segmentation and processing on which a child’s early reading abilities and academic success may rest.

Crucially, the present study has the potential to benefit society by illustrating the nature of infants’ early sensitivities to language, and when they must occur in development; indeed, the results provide powerful support that infants’ early exposure to signed language is essential for optimal brain, language, and reading growth. 

Since enrolling in the PEN Program at its inception in Fall 2013, Mr. Stone has been a graduate research assistant in Dr. Petitto’s Brain & Language Laboratory for Neuroimaging (BL2) and a student-scholar in the National Science Foundation (NSF) Science of Learning Center, Visual Language and Visual Learning (VL2). 

Mr. Stone’s research interests center on better understanding the neurobiological foundations of human language, with a special focus on the role of visual language and the rhythmic-temporal patterning underlying phonological organization in young deaf children’s language, reading, and literacy development.  He is certified in the use of functional near infrared spectroscopy (fNIRS) neuroimaging with infants, children, and adults and in advanced neuroimaging data analysis.  He has led pioneering work in BL2 on integrating fNIRS with other tools (eye tracking, thermal imaging to measure human attention and emotional engagement) in order to answer new scientific questions about language acquisition and reading development in infants and children with different language experiences.

Mr. Stone’s dissertation study was supported by two grants to his primary advisor, Dr. Laura-Ann Petitto: a W.M. Keck Foundation grant (“Seeing the rhythmic temporal beats of human language,” Petitto, PI) and a NSF INSPIRE grant (“The RAVE revolution for children with minimal language exposure,” Petitto, PI, IIS-1547178).  Additional funding for Mr. Stone’s graduate studies came from the following sources: A NSF VL2 Subaward to Dr. Petitto (“The impact of early visual language experience on visual attention and visual sign phonology processing,” Petitto, PI, SBE-1041725), VL2 graduate student research scholarships (Petitto & Allen, Co-PIs, SBE-1041725), a NIH NRSA F31 Individual Predoctoral Fellowship (“Neural systems for infant sensitivity to phonological rhythmic temporal patterning, 1F31HD087085), the Society for Neuroscience’s Neuroscience Scholars Program, and a Florence Foederer Graduate Fellowship from Gallaudet University.”

The members of Mr. Stone’s dissertation committee included Professor Laura-Ann Petitto, Ph.D. Program in Educational Neuroscience and Department of Psychology, chair of the dissertation committee; Professor Maribel Gárate, Department of Education; Dr. Clifton Langdon, Ph.D. Program in Educational Neuroscience; Professor Regina Nuzzo, Department of Science, Technology, and Mathematics and Department of Psychology; and Professor April Benasich, Center for Molecular and Behavioral Neuroscience, Rutgers University.