This study with genetically modified mice is the first to show that short but repeated learning sessions can slow a process known for causing the protein beta amyloid to clump in the brain and form plaques, which disrupt communication between cells and lead to symptoms of Alzheimer's disease.

Learning also was found to slow the buildup of hyperphosphorylated-tau, a protein in the brain that can lead to the development of tangles, the other signature lesion of the disease. Scientists say these findings have large implications for the understanding and treatment of Alzheimer's disease, as it is already known that highly educated individuals are less likely to develop the disease than people with less education.

"This study shows learning can delay the progression of Alzheimer's neuropathology in mice genetically engineered to develop this insidious disorder, and learning also delays the cognitive decline," said Frank LaFerla, professor of neurobiology and behaviour at the University of California and co-author of the study. "These remarkable findings suggest stimulating the mind with activities such as reading books or completing crossword puzzles may help delay and/or prevent Alzheimer's disease in senior citizens."

The researchers studied hundreds of mice that were bred to develop the plaques and tangles characteristic of the disease. Mice in one group were allowed to "learn" by swimming in a round tank of water until they found a submerged platform on which to stand. After 12 months the mice that had learned developed levels of beta amyloid and hyperphosphorylated-tau that were 60 percent less than the mice that had not learned; but, by 15 months of age, the mice that had learned deteriorated and were identical both physically and cognitively to the mice that had not learned.

MEDICA.de; Source: University of California - Irvine