Dissociable effects of self-reported daily sleep duration on high-level cognitive abilities

This study investigated how self-reported sleep duration affects cognitive abilities in over 10,000 adults. It found that both insufficient (less than 7 hours) and excessive (more than 8 hours) sleep impaired reasoning, verbal abilities, and overall cognition. Short-term memory was unaffected by sleep duration. On average, sleeping 4 hours per night reduced cognitive performance to levels comparable to aging 8 years. Encouragingly, sleeping closer to the optimal amount of 7–8 hours, even for one night, improved cognition. These findings suggest the importance of maintaining regular, adequate sleep to support brain health and daily problem-solving.

Aim for 7–8 hours of sleep per night to optimize reasoning and communication skills. If sleep patterns are irregular, focus on aligning closer to the optimal duration. Even one good night's sleep can improve cognitive performance. These results are robust across age groups but rely on self-reported data, so individual differences in sleep needs should also be considered.