Date of Award


Document Type


Degree Name

Doctor of Psychology (PsyD)



First Advisor

David J. LaPorte, Ph.D.

Second Advisor

William M. Meil, Ph.D.

Third Advisor

William J. Farrell, Ph.D.


This study investigated whether or not partial chronic sleep restriction would unmask residual memory deficits in individuals with a history of a mild TBI. It was hypothesized that 1) there would be a significant difference in performance on attention and memory tasks between the control group and the TBI group, and 2) there would be a significant difference in performance on attention and memory tasks between individuals with one TBI and individuals with multiple TBI. Method: A total of 42 undergraduate students from the Indiana University of Pennsylvania were enrolled in the study. Data from only 30 subjects were analyzed after 12 subjects were excluded due to non-compliance with sleep restriction requirements. Subjects in the control (no mild TBI) and experimental (at least one mild TBI) groups were administered the Degraded Stimulus –Continuous Performance Test (DS-CPT) and the Rey Auditory Verbal Learning Test (RAVLT) at baseline and after restricting their sleep to six hours per night over four nights. All subjects were instructed to utilize the SleepTime smartphone application to collect objective sleep data each night leading up to their second testing session. Results: Results of a mixed multivariate analysis (MANOVA) revealed non-significant findings at p < .05 (Wilks λ=.892, F [7, 22]=.381, p=.903, η2=.108). A meaningful statistical analysis could not be run to test the second hypothesis due to an inadequate sample size, variability of sample size per cell, and insufficient power. Conclusion: The first hypothesis was not supported as there was no statistically significant difference in attention and memory outcomes at baseline and post-test between the control group and mild TBI group. As noted above, the second hypothesis could not be tested. Findings from this study are consistent with previous literature on TBI recovery that suggests individuals with one or more mild TBI typically recover cognitively within three to four months of the injury. Implications, limitations, and future directions are discussed.