One of the most pervasive and insidious threats to human health, safety and performance is fatigue due to sleep loss.1 Given the nature of the 24 h society found in most industrialised nations, often revolving around work schedules, family and hobbies, it is understandable that a growing number of adults report that they habitually receive less than 6 h of sleep each night.2 ,3 Chronic insufficient sleep contributes not only to general feelings of tiredness but also to significant impairments on most measures of neurobehavioral and cognitive performance,4 as well as higher rates of certain medical problems such as diabetes, obesity and cardiovascular disease.1 ,2 Moreover, chronic fatigue is also thought to contribute to increased rates or severity of certain psychological disorders, including depression and anxiety.2 Strategic naps can help to mitigate some of the effects of fatigue but the sleep inertia often experienced on awakening may be a concern in some environments.5 It is hardly surprising then that, …