Fletcher, Jack M.Ewing-Cobbs, Linda2018-11-262018-11-26August 2012013-08August 201http://hdl.handle.net/10657/3394The purpose of this dissertation was to investigate the developmental trajectories of verbal and visual-spatial WM in children following traumatic brain injury, and to determine how age at injury and injury severity affects growth. As part of a larger assessment, the sample included 42 children with severe head injury, 13 children with complicated mild-moderate head injury, and 47 children with orthopedic injury. Longitudinal data was collected at 2, 6, 12 and 24 months post-injury. A multivariate approach to individual growth curve modeling was utilized and the data was centered at 12 months post-injury. Results indicated that at 12 months post-injury, children in all three injury groups with varying age at injury did not differ significantly on verbal or visual-spatial working memory performance. The injury groups did not differ on working memory performance when age at injury was held constant. A significant rate of change (slope) by age at injury by injury group interaction for verbal working memory (and a similar pattern for visual-spatial working memory) revealed that children injured at a younger age with more severe injuries demonstrated the slowest working memory growth, but that as age at injury increased, older children with severe injuries exhibited faster growth. A significant positive relation was found between level of performance on verbal and visual-spatial working memory tasks at 12 months post-injury, but not for rate of growth. This study lends further support to an early vulnerability hypothesis, which suggests that children brain-injured at a younger age are more vulnerable to cognitive deficits.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).Traumatic brain injuryPediatricsChildrenHead injuryWorking memory2018-11-26Thesisborn digital