Sleep Loss and Sleepiness: Physiological and Neurobehavioral Effects

The effects of sleep loss and sleepiness encompass a variety substantial costs to society; the direct economic costs owing of neurobehavioral and physiologic alterations. This chapter to insomnia are estimated at $13.9 billion (2). The etiology reviews the causes, consequences, and mechanisms of sleep of these symptoms has not been clearly delineated, however. disruption and concomitant daytime sequelae, namely The causal explanation that sleep deprivation accounts for sleepiness and neurobehavioral performance decrements. the impairment of daytime functioning in insomniacs has Given the personal distress, quality of life issues, public been challenged and needs re-evaluation. This section pro-health concerns, and economic costs of sleep loss and sleepi-vides a review of the daytime sequelae of the insomnia and ness, it is imperative that researchers and practitioners strive a discussion of alternative mechanisms that may account to obtain a solid understanding of these consequences and for the daytime symptoms experienced. mechanisms. Several advances in the psychopharmacologic and behavioral treatments of the causes and consequences of sleep loss have recently evolved. Technologies are rapidly Consequences developing and showing promise for effective evaluation of these highly prevalent problems. Persons with insomnia report various somatic complaints Advances and online monitoring and mathematical and demonstrate increased health-seeking behaviors. The modeling of sleepiness and associated neurobehavioral primary complaints among insomniacs include drowsiness forms are rapidly evolving novel behavioral and psychophar-and tiredness on awakening, as well as sleepiness throughout macologic treatments effective for the causes and conse-the day (3,4). Insomniacs complain of physical ailments quences of sleep loss. such as headache, diarrhea, stomach discomfort, heart palpi­ tations, pain, tiredness, and weakness more frequently than do controls (5). Health-seeking behaviors such as hospital and physician visits are more frequent among a clinical sam-PATHOPHYSIOLOGY OF DIFFICULTY ple of insomniacs compared to controls (5). Cardiovascular INITIATING OR MAINTAINING SLEEP disease (6) and decreased immune functioning (7) may also be exacerbated in chronic insomnia. Insomnia is characterized by difficulty initiating or main-The quality of life among insomniacs also appears to be taining sleep that results in psychological distress and im-diminished (8). Absenteeism, and work and social limita­ paired social or occupational functioning (1). Individuals tions are significantly more prevalent among insomniacs with insomnia report a myriad of interpersonal, cognitive, compared to normal sleepers (5,8). Insomniacs report re-affective, behavioral, and physical symptoms. Not only are stricted physical activities, poorer health, less vitality, and there consequences for the individual, but also are there a decreased …