Daydreaming and Alzheimer's disease
The AP points to a new study in this week's Journal of Neuroscience that posits a causal link between daydreaming and Alzheimer's disease:
A new Washington University study shows the part of the brain used to daydream is the same where Alzheimer's disease develops -- in some people -- later in life. It suggests the normal brain activity of daydreaming fuels the sequence of events leading to Alzheimer's.
"The implication, albeit a speculative one, is that those activity patterns in young adults are the foothold onto which Alzheimer's disease forms," said lead researcher Randy Buckner, associate professor of psychology. He said they may lead to a life-long cascade that ends in Alzheimer's disease in some people. [...]
Researchers at Washington University and the University of Pittsburgh used five imaging techniques to map the brains of 764 people. The subjects fell into three groups -- people in their 20s, and older people with either early-stage dementia, or Alzheimer's disease.
When they compared images, they found that parts of the brain involved in musing, daydreaming or recalling pleasant memories in young people were where evidence of Alzheimer's disease appears.
The study prompts several interesting hypotheses. Maybe zoning out is intrinsically hazardous in excess. Daydreaming might be intrinsically harmless but ultimately detrimental if it cuts into time spent in healthy mental exertion. Or, perhaps the Alzheimer's disease process begins earlier in life than we usually assume.
The researchers readily acknowledge that their research is speculative. They aren't claiming to have established any causal links yet, let alone established which of the many logically possible relationships might be operative.