The brain remains interconnected during non-REM sleep, which was thought not to happen, reports Science Daily.
Sleep is composed of various cycles in which there are different stages: slow and fast-wave, which make up non-REM sleep and REM sleep. During the night, it is normal to experience four or five complete cycles, each lasting around ninety minutes.
Various investigations have shown that communication between different areas of the cerebral cortex is interrupted during non-REM sleep and also when a patient is under anaesthesia, due to the loss of consciousness.
“It was thought that the brain disconnected during non-REM sleep and that the individual areas could no longer communicate effectively,” explained Umberto Olcese, a researcher from the Swammerdam Institute for Life Sciences of the University of Amsterdam (Netherlands).