“Sleep is critical to the function of the brain's waste removal system and this study shows that the deeper the sleep the better. These findings also add to the increasingly clear evidence that quality of sleep or sleep deprivation can predict the onset of Alzheimer's and dementia.”

The glymphatic system only works when we sleep. Basically, it operates by compressing brain cells and pumping cerebral spinal fluid into the brain. This fluid cleanses out waste products, including the protein beta-amyloid, which is implicated in Alzheimer’s.

Summary:
Scientists discover a new way to diagnose Alzheimer's disease by analyzing the levels of specific proteins in nasal discharge. This simple and inexpensive method could help in timely diagnosis of Alzheimer's disease, in order to start treatment as soon as possible, thus delaying disease progression.

People who are organized, with high levels of self-discipline, may be less likely to develop mild cognitive impairment as they age, while people who are moody or emotionally unstable are more likely to experience cognitive decline late in life, according to new research.
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The research, published in the Journal of Personality and Social Psychology, focused on the role three of the so-called "Big Five" personality traits (conscientiousness, neuroticism and extraversion) play in cognitive functioning later in life.

"Personality traits reflect relatively enduring patterns of thinking and behaving, which may cumulatively affect engagement in healthy and unhealthy behaviors and thought patterns across the lifespan," said lead author Tomiko Yoneda, PhD, of the University of Victoria.
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Future research is necessary on more diverse samples of older adults and should include the other two of the big five personality traits (agreeableness and openness) to be more generalizable and provide a broader understanding of the impact of personality traits on cognitive processes and mortality later in life, she said.