During a deep sleep, when a sewage system is trapped inside the high gear within the brain. This lack of sleep increases the development of toxic protein in the brain, which is called 'beta amyloid'. Without this the memory of the gold brain is locked and it cannot be new to memory.
We certainly know that the lack of sleep will actually prevent your brain from being able to create new memories. The effects of body in the absence of sleep and if you are not getting enough sleep and more toxic proteins will be created every night and in later life the risk of dementia will develop. Since its washing began, the toxic protein beta amyloid has been dispelled.