A recent study from University College London indicates that sleeping less than 7 hours or more than 9 hours daily may negatively impact cognitive performance, including memory and reaction time.Results showed that individuals sleeping less than 7 hours daily made 5% more errors in visual memory tests, while those sleeping over 9 hours made 9% more errors. Findings were published in the British Journal of Epidemiology. Co-author Dr. Victoria Garfield recommends most healthy adults maintain daily sleep within the 7-9 hour range.
However, researchers noted that further studies are needed to clarify the relationship between sleep duration and cognitive performance changes. Currently, there is limited evidence linking sleep duration to the risk of developing Alzheimer's disease. (Zhang Jiawei)