Sleep does not help brain wash out toxins, study suggests

Finding that clearance of fluid in mice brains is lower in sleep and anaesthesia runs counter to dominant view in neuroscience

The restorative effect of a good night's rest is widely recognised and the popular scientific explanation has been that the brain washes out toxins during sleep.

However, new findings suggest this theory, which has become a dominant view in neuroscience, could be wrong. The study found that the clearance and movement of fluid in the brains of mice was, in fact, markedly reduced during sleep and anaesthesia.