Rehabilitation or Recovery Sleep: A Future Potential Therapeutic Target for Sleep Deprivation

Sleep is a period of relaxation and repair. During sleep, waste products of brain metabolism are removed. It plays central role in maintenance of physiological homeostasis and psychological balance. Sufficient sleep helps us think more clearly, complete complex tasks better and more consistently. One of the important function of sleep is to promote synaptic plasticity and neuronal recovery for proper brain functioning. Memory consolidation, brain growth and repair are other functions proposed for sleep. Problems related to sleep deprivation are being increased in today's modern society. Every day there seems to be twice as much work and half as much time to complete it, this results in a decrease in sleep or extended periods of wakefulness. Sleep deprived individuals may not have difficulty of verbal disturbances but research studies have shown that individuals have more difficulty in reacting well, to taking biological discussion and implementing the task with efficiency of action. Although day time performance due to sleep loss is experienced universally but in professionals such as paramilitary forces, army personals, who work under stressful conditions are more vulnerable to the sleep deprivation. These conditions become more stressful during emergencies and war because, after periods of extended wakefulness neurons may begin to malfunction, visibly affecting person's behavior. Rapid eye movement (REM) sleep plays a role in learning due to an activation of the hippocampus involved in encoding new memories. Many experiments have shown that the day after a good night's sleep, one may retain newly acquired knowledge or a newly learned skill more effectively. An enriched environment (EE) which is a complex combination of social, cognitive, and physical stimulation, improves learning and memory. Many changes such as increased brain weight, synaptic plasticity, gliogenesis, growth of dendritic spine as well as change in neurotransmitter content, up regulation of neuronal signaling molecules, neurotrophin levels and adult hippocampal neurogenesis have been reported.