Cognitive Labs

WASHINGTON (AP) — Researchers have uncovered a new clue to the cause of Alzheimer's disease. The brains of people with the memory-robbing form of dementia are cluttered with a plaque made up of beta-amyloid, a sticky protein. But there long has been a question whether this is a cause of the disease or a side effect. Also involved are tangles of a protein called tau; some scientists suspect this is the cause.

Now, researchers have caused Alzheimer's symptoms in rats by injecting them with one particular form of beta-amyloid. Injections with other forms of beta-amyloid did not cause illness, which may explain why some people have beta-amyloid plaque in their brains but do not show disease symptoms.

Full story on Google News

On Nature Medicine

Labels: alzheimers, amyloid, harvard, rats, selkoe, shankar, Tau

learning exercise for rats: they are good swimmers by nature

Want to learn more about Neurogenesis? Scientists know now that adults can create new brain cells, but what do they do? Are they like extra furniture in a room? Or do they interact with existing structures in a meaningul - and beneficial way?

by David Dobbs, Editor, Mind Matters

After a sometimes ferocious debate lasting decades, most neuroscientists now agree that the adult brain makes new neurons. Yet they're far from agreeing on what, if anything, these freshly minted new brain cells actually do. Do they replace worn-out veterans? Provide new memories? Strengthen existing knowledge? Just take up space? These questions hang over every discussion of neurogenesis -- and drive quite a few research agendas.

The paper reviewed here -- "Preferential incorporation of adult-generated granule cells into spatial memory networks in the dentate gyrus," by Nohjin Kee, Catia M. Teixeira, Afra H. Wang, and Paul W. Frankland, from Nature Neurosciece 4 Feb 2007 -- suggests some answers. As our experts Doug Fields and Brad Aimone explain, this paper shows that at least some new neurons help us form memories -- and suggests other intriguing possibilities as well.

Join us in a look at how new neurons go to work.

read more at Scientific American Mind.

Labels: neurogenesis, rats, sciam