Behavioral and Genetic Markers of Sleepiness

Abstract

S19Neurobehavioral responses to acute total and chronic partial sleep deprivation occur in healthy adults and are particularly evident in vigilant attention performance. There are large inter-individual differences in the degree of cognitive deficitssuch differences are manifested in proportionality between the mean and variance as sleep loss progresses. It has recently been demonstrated via laboratory experiments that differential neurobehavioral vulnerability to sleep deprivation is not random-but rather is stable and trait-like-strongly suggesting a phenotypic response with possible genotypic involvement. These experiments also showed that vulnerability was not explained by subjects' baseline functioning or a number of other potential predictors. Differential vulnerability has been shown to extend to chronic partial sleep deprivation. One potential genetic biomarker for such differential vulnerability is the human leukocyte antigen (HLA) DQB1*0602, an allele which we recently demonstrated predicts interindividual differences in sleepiness, physiological sleep, and fatigue to chronic partial sleep deprivation in healthy adults. Determination of biomarkers of individual differences to sleep loss will help identify those individuals in the general population who are most in need of prevention of sleep debt and in need of effective countermeasures for sleep loss; will further understanding and management of vulnerability to excessive sleepiness due to common sleep and medical disorders; and will inform public policies pertaining to the need for adequate sleep. S u p p l e M e n t prevalence and Consequences of Sleep lossStudies estimate that 20% to 40% of the adult US population sleep less than 7 hours per night 1 -the minimum sleep duration necessary to prevent cumulative deterioration in performance on a range of cognitive tasks.2,3 The proportion of people curtailing their sleep due to lifestyle is increasing, 1 and is likely higher than surveys indicate, since physiological sleep duration is typically at least one hour less than self-reported sleep duration.4,5 Moreover, sleep loss has become a significant public health concern as population studies have found reduced sleep duration (less than 7 hours) associated with increased risks of obesity, morbidity, and mortality. [6][7][8] Sleep loss, including chronic partial sleep deprivation (PSD)-a condition experienced by millions of people on a consecutive and daily basis-can result from medical conditions, sleep disorders, work demands, stress/emotional distress, and social/domestic responsibilities.1 In addition, for the majority of people, sleep loss directly causes significant risks via increased fatigue and sleep propensity, and via deficits in mood and neurocognitive functions including vigilant and executive attention, cognitive speed and working memory, and executive functions. 1,9,10 Stable trait-like Individual Differences in Response to Sleep lossOur laboratory was the first to experimentally demonstrate that subjects undergoing acute total sleep dep...

Circadian Rhythms, Sleep Deprivation, and Human Performance

“…32,148,172,173 Some individuals are highly vulnerable to neurobehavioral performance deficits when sleep deprived, others demonstrate remarkable levels of neurobehavioral resistance to sleep loss, and others show intermediate responses. 171,174 Thus far, studies from our laboratory and others indicate these phenotypic responses occur as a normal distribution, 170,175 which suggests the phenotype, like chronotype, may be polygenetic.…”

Habitual sleep duration associated with self-reported and objectively determined cardiometabolic risk factors

“…This may be due to reporting characteristics, since the “short sleep” group may be more heterogeneous and may be more likely to include more individuals who are relatively unimpaired due to being a “natural short sleeper” who requires less sleep[17, 79] or may be more resilient to sleep loss[80-83], in addition to those who are obtaining insufficient sleep. This underscores the need for further research identifying and classifying subgroups of short sleepers who may be at increased (or decreased) risk of adverse outcomes.…”

Sleep deprivation and neurobehavioral dynamics

“…While some individuals are highly vulnerable to performance deficits when sleep deprived, others show remarkable levels of neurobehavioral resistance to sleep loss, and the remainder display intermediate responses [44,48] (Figure 3). Thus far, our laboratory studies indicate these responses occur as a normal distribution [43], which suggests they may be a polygenetic trait.…”