Dissertation defense by Clifton Langdon
To: Students, Faculty and Staff
From: Carol J. Erting, Ph.D., Dean of the Graduate School
Re: Dissertation Defense for Mr. Clifton Langdon
It is my pleasure to announce that Mr. Clifton Langdon, a Ph.D. candidate in the Department of Linguistics, will defend his dissertation on "The Linguistic Structure and Neural Representation of Classifier Constructions: Through the Lens of Child Acquisition and Adult Usage" on Wednesday, December 11, at 3 p.m. in the Living and Learning Residence Hall (LLRH6), Room 101. The first forty minutes of the dissertation defense are open to the Gallaudet community.
Mr. Langdon's study addresses a division in the field of sign language linguistics over the potential role of iconic motivation in classifier constructions, i.e., whether classifier constructions are partially composed of gesturally motivated components. The study starts with a first-time direct comparison of two central analyses representing the field's opposing views with respect to a child language corpus, and finds that neither of the two approaches offers a decisive advantage over the other. The study then introduces a set of predicted neural signatures based on assumptions of these linguistic analyses and findings from the fields of cognitive neuroscience and neurolinguistics. The predictions are tested in an neuroimaging experiment designed for adults, and the neuroimaging data trends towards significance in support of linguistic proposals that recognize a grammatical system enabling iconicity to carry a role in the processing of language. This finding has powerful implications for both cognitive neuroscience and linguistics. In cognitive neuroscience, this finding advances our understanding of the neural representation of language. In linguistics, this finding indicates that future linguistic analyses of classifier constructions can now reflect neural bases of language processing.
The members of Mr. Langdon's dissertation committee are Dr. Deborah Chen Pichler, chair of the dissertation committee, Department of Linguistics; Dr. Paul Dudis, Department of Linguistics; Dr. Gaurav Mathur, Department of Linguistics; and Dr. Daniel Koo, Department of Psychology.
Mr. Langdon's work within the fields of linguistics and cognitive neuroscience asks questions about the structure of language with an emphasis on language acquisition. His expertise in advancing these questions has been supported by working in a number of renowned research laboratories since 2005 under the supervision of Dr. Karen Emmorey, Dr. Robin Thompson, Dr. Paul Dudis, Dr. Deborah Chen Pichler, and Dr. Laura-Ann Petitto. His theoretical interests are integrated into three closely related thrusts: (i) the linguistic structure of classifier constructions as a testing ground for the neurobiological (dis)similarities of spoken and signed languages; (ii) the effects of delayed language acquisition in relation to different neural representations of language processing (i.e. the neuroplasticity of language); and (iii) the neuroplasticity of the auditory cortex as it relates to atypical aquisition of spoken and signed languages. His current research sets the stage for the next series of questions about age of language exposure and its impacts on how the human mind processes linguistic structures. Particularly, these questions have profound implications on our understanding of the developing human brain and how it supports language acquisition when children acquire a language later in the sensitive period for language acquisition.
Please join me in extending best wishes to Mr. Langdon for his dissertation defense.