Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

William F. Waters


Subjects who had sustained a mild head injury (MHI) and uninjured control subjects were examined before and after 36 hours of sleep deprivation. MHI subjects and uninjured controls were selected from among individuals who scored above the 50$\rm\sp{th}$ percentile on the Postconcussion Syndrome Checklist (PCSC), a measure designed to assess the frequency, intensity and duration of postconcussion symptoms. Sixty subjects were divided into four groups: Head injured/sleep deprived, head injured/non-sleep deprived, uninjured/sleep deprived, and uninjured/non-sleep deprived. Performance was compared among the groups on the Selective Reminding Test (SRT) and the Paced Auditory Serial Addition Test (PASAT), which are designed to measure memory and new learning, and information processing, respectively. The SRT and the PASAT were administered to all subjects three times: Learning trial, pre-sleep deprivation trial, and post-sleep deprivation trial. Performance did not differ between groups on any aspect of the SRT or PASAT post-sleep deprivation. A significant trials effect was found, in which performance declined across administrations for all groups on the Delayed Recognition and Delayed Recall aspects of the SRT prior to sleep deprivation. The performance of all groups steadily improved across trials on the PASAT prior to sleep deprivation. There was no effect of sleep deprivation on the SRT or PASAT performances. Results indicated that MHI subjects can maintain a level of performance commensurate with that of uninjured controls following 36 hours of sleep deprivation. A number of factors may have prevented relations between head injury, sleep deprivation, and performance from emerging: (1) MHI subjects may not have sustained an injury severe enough to result in diffuse brain injury or produce neuropsychological deficits; (2) MHI and uninjured subjects endorsed PCS symptoms at a level that was one and one-half standard deviations lower than would be considered clinically significant for PCS; (3) the duration of sleep deprivation may not have been long enough to elicit performance deficits on neuropsychological measures; and (4) the neuropsychological measures administered may not have been of sufficient duration to elicit performance decrements following sleep deprivation.