Which cognitive domain is affected by lack of sleep?

Which cognitive domain is affected by lack of sleep?

• A. Vigilance
• B. Mood
• C. Blood pressure
• D. Temperature

Answer: (A)

Lack of sleep primarily compromises vigilance—the ability to stay alert and maintain attention over time. When sleep is missing, performance on tasks that require constant monitoring and quick responses drops, reaction times slow, and I slips or micro‑sleeps become more likely. This reflects a deficit in sustained attention and arousal, core aspects of cognitive functioning that rely on wakefulness and frontal-lobe networks. Mood can be affected by sleep loss, but that’s an affective change rather than a cognitive domain. Blood pressure and temperature are physiological measures, not cognitive processes. So the best answer is vigilance.

Lack of sleep primarily compromises vigilance—the ability to stay alert and maintain attention over time. When sleep is missing, performance on tasks that require constant monitoring and quick responses drops, reaction times slow, and I slips or micro‑sleeps become more likely. This reflects a deficit in sustained attention and arousal, core aspects of cognitive functioning that rely on wakefulness and frontal-lobe networks. Mood can be affected by sleep loss, but that’s an affective change rather than a cognitive domain. Blood pressure and temperature are physiological measures, not cognitive processes. So the best answer is vigilance.