WASHINGTON — The brain areas involved in daydreaming, musing and other stream-of-consciousness thoughts appear to be the same regions targeted by Alzheimer's disease, researchers are reporting today in a study that offers new insights into the roots of the deadly illness.

The strong correlation between the two suggests there might be a link between the sort of thinking that people regularly do when not involved in purposeful mental activity and the degenerative disease that is characterized by forgetfulness and dementia, said scientists who conducted the federally funded study.

Randy Buckner, a neuroscientist at Washington University in St. Louis, said the implications of the finding are far from clear.

It is too early to suggest that daydreaming is dangerous, he said, or that avoiding such musings could make a difference to the risk of Alzheimer's disease. Rather, he and others said, the study adds to the evidence that everyday mental and physical activities play an important role in the course of neurological disease.

"It suggests an avenue between brain activity patterns and Alzheimer's disease that we just hadn't been thinking about," said Buckner, who led the study.

Alzheimer's disease affects as many as 4.5 million Americans. It is a degenerative brain disease that erodes thought, language and memory.

Aspirin dose found of little use in cancer

CHICAGO — A large study of women weakens hopes that low doses of aspirin could be an easy way to prevent colorectal cancer.

Aspirin helps, but its effect is significant only after a decade of use, according to a 20-year study of almost 83,000 nurses published in today's Journal of the American Medical Association.

Low doses of aspirin did not lower cancer risk significantly. High doses of aspirin — such as two or more aspirin per day — reduced colon cancer risk by a third but also were linked to dangerous bleeding.

A high-dose aspirin regimen that prevented one or two cases of colorectal cancer also would cause eight additional cases of serious bleeding from irritation of the stomach or intestines, the researchers estimated.

"We can't make a recommendation that you could take an aspirin a day to prevent both heart disease and colorectal cancer," said study co-author Dr. Andrew Chan, a researcher at Harvard Medical School.

The best prevention is regular screening, exercise and eating a high-fiber, low-fat diet, he said.

Quick detox method contested in study

CHICAGO — Internet ads for "ultra rapid detox" using anesthesia promise pain-free withdrawal from heroin and prescription painkillers.

But the technique can be life-threatening, is not pain-free and has no advantage over other methods, a new study of 106 patients found.

The study, the most rigorous to date on the method, showed that patients' withdrawal was as severe as those of addicts undergoing other detox approaches.

"Anyone who tells you it's painless can only honestly be referring to the period the person is under anesthesia," said co-author Dr. Eric Collins of Columbia University Medical Center.

The study appears in today's Journal of the American Medical Association.

Compiled from The Associated Press