Fletcher, Jack M.2014-12-192014-12-19May 20132013-05http://hdl.handle.net/10657/844The present study focused on bilateral variation in the structure (single, duplicated) and size (left or right asymmetry) of the Heschl’s gyrus (HG) in individuals with spina bifida meningomyelocele (SBM). A higher rate of anomalous HG was predicted in the SBM population, particularly in individuals with SBM that presented with atypical handedness and greater frequency of clinical and neural markers. The anomalous HG presentation was predicted to relate to lower verbal and reading performance as well as either a reduced or absent right ear advantage on a dichotic listening task. Children and adults were recruited from an existing cohort, along with typically developing (TD) participants. All participants completed both an MR imaging protocol and a battery of cognitive tests including: verbal and spatial intelligence, reading and math achievement, and monotic and dichotic listening. The structure status of the participants’ HG (single, duplicated) was determined through qualitative coding of MRI scans, and asymmetry of the HG was determined through automated quantification of the HG volume. The results did not indicate a higher rate of anomalous HG (duplicated, right HG asymmetry) in individuals with SBM, and the rate of anomalous HG was also not associated with left hand preference, or with more severe clinical and neural pathology. There was evidence that having anomalous HG led to slightly higher verbal and reading scores in the SBM group. These effects, however, were small compared to the larger influences of socioeconomic status and SBM. Although participants’ group status (TD, SBM) and age influences ear advantage on the dichotic listening task, there was no effect of anomalous HG status. The results suggest that the development of an anomalous HG is separate from the common congenital maldevelopment that occurs in SBM, and the presence of an anomalous HG may contribute to higher verbal and reading performances in this clinical population.application/pdfengThe author of this work is the copyright owner. UH Libraries and the Texas Digital Library have their permission to store and provide access to this work. Further transmission, reproduction, or presentation of this work is prohibited except with permission of the author(s).Heschl's GyrusImagingSpina bifidaClinical psychology2014-12-19Thesisborn digital