The Role of Sleep in Cognitive Function: The Value of a Good Night's Rest.

As a universal, evolutionarily conserved phenomenon, sleep serves many roles, with an integral role in memory. This interplay has been examined in a variety of research. The purpose of this article will be to review the literature of sleep, aging, cognition, and the impact of two common clinical conditions (obstructive sleep apnea and insomnia) on cognitive impairment. This article will review data from meta-analyses, population studies, smaller cohort studies, neuropsychological studies, imaging, and bench data. Considerations are given to the current data trends and their limitations. This paper will explore the impact of sleep on cognitive impairment. Finally, we will conclude with integrating the separate mechanisms towards more generalized common pathways: disruption of sleep quality and reduction in sleep quantity lead to excessive neuronal activity without sufficient time for homeostasis. Sleep apnea and chronic insomnia can lead to oxidative stress and neuronal damage. These changes predispose and culminate in the development of cognitive impairment.