Abstract
Sleep is essential for various cognitive, affective, and behavioral processes, including attention, memory, executive function, emotional regulation, and interpersonal interactions. Sleep disruptions undermine these functions, resulting in measurable impairments in daily activities, occupational performance, and public safety. Adequate sleep supports sustained vigilance and concentration, whereas sleep deprivation is associated with attentional lapses, diminished cognitive control, and impaired sensory processing. Memory consolidation, which depends on both non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, is particularly susceptible to disruption by sleep loss. Executive functions, such as working memory, impulse control, and decision-making, are notably impaired due to the prefrontal cortex's heightened sensitivity to insufficient sleep. Sleep deprivation increases amygdala reactivity, weakens prefrontal-amygdala connectivity, and contributes to emotional dysregulation, impulsivity, and risk-taking behaviors. Chronic sleep deprivation exacerbates cognitive deficits, emotional instability, and motor performance decline, leading to higher error rates and reduced workplace productivity. Given its widespread consequences, chronic sleep deprivation constitutes a significant public health concern. This narrative review synthesizes contemporary research on the effects of sleep and sleep loss on waking behavior, with a focus on attention, memory, executive function, emotional regulation, and daytime performance.