Brain function during sleep deprivation: multimodal approaches to understanding group and individual differences in cognitive vulnerability
This talk will review a series of studies in which we have examined the cognitive consequences of sleep deprivation, utilizing both functional magnetic resonance imaging (FMRI) and cognitive and neuropsychological testing. These studies have examined a wide range of cognitive domains, including verbal memory, attention, various aspects of working memory, and decision making. Our FMRI data has shown that the cerebral response to a cognitive challenge during sleep deprivation is influenced by a variety of factors, including the cognitive process measured, the length of sleep deprivation, and individual differences. Based in part on these data, we have proposed a compensatory recruitment hypothesis. This hypothesis states that, during sleep deprivation, the brain can recruit additional cognitive resources it does not typically use to perform a task well rested in order to maintain relatively intact performance. Importantly, there appear to be individual differences in the extent of this compensation, and the more a given individual is able to engage in this mechanism, the better that person is likely to perform during sleep deprivation. This talk will also review a series of behavioral studies examining the impact of sleep deprivation on decision making and using computational modeling to tease out the effects of sleep deprivation on specific components of verbal working memory.