The article by Alhola and Polo-Kantola reviews the impact of sleep deprivation on cognitive performance, distinguishing between acute total sleep deprivation (SD) and chronic partial sleep restriction. Both types of SD impair cognitive functions, particularly attention and working memory, but also affect long-term memory and decision-making. Acute SD, often studied due to its prevalence in real-life scenarios, is more thoroughly researched than chronic SD. The mechanisms behind these impairments include decreased alertness, attention lapses, and wake-state instability. Individual differences, such as aging and gender, influence the severity and recovery from SD. Aging individuals generally tolerate SD better than younger subjects, possibly due to changes in sleep architecture and circadian rhythms. Gender differences are less clear but may be influenced by physiological and social factors. Interindividual variability in response to SD is significant, with some individuals being more vulnerable than others. The recovery process from SD is also discussed, with cognitive performance improving after adequate sleep, though the recovery rate varies with the type and duration of SD. The article highlights the need for further research to understand the complex interactions between sleep, cognitive performance, and individual differences.The article by Alhola and Polo-Kantola reviews the impact of sleep deprivation on cognitive performance, distinguishing between acute total sleep deprivation (SD) and chronic partial sleep restriction. Both types of SD impair cognitive functions, particularly attention and working memory, but also affect long-term memory and decision-making. Acute SD, often studied due to its prevalence in real-life scenarios, is more thoroughly researched than chronic SD. The mechanisms behind these impairments include decreased alertness, attention lapses, and wake-state instability. Individual differences, such as aging and gender, influence the severity and recovery from SD. Aging individuals generally tolerate SD better than younger subjects, possibly due to changes in sleep architecture and circadian rhythms. Gender differences are less clear but may be influenced by physiological and social factors. Interindividual variability in response to SD is significant, with some individuals being more vulnerable than others. The recovery process from SD is also discussed, with cognitive performance improving after adequate sleep, though the recovery rate varies with the type and duration of SD. The article highlights the need for further research to understand the complex interactions between sleep, cognitive performance, and individual differences.