The leaves of Ginkgo biloba have an extensive reasearch history behind them, although their therapeutic use is fairly recent. Though many claims have been made about this ancient tree (mostly relating to memory, energy, mental function), there are some clear indications and effects that almost everyone agrees on: first, ginkgo increases circulation; second, it has a marked antioxidant and cell-protective effect; third, it influences biochemical mechanisms in the blood resulting in an net reduction of clotting power.
Recently, based primarily on the first two facts listed above, researchers have been focusing on ginkgo's use in treating Alzheimer's-related dementia. A trial released in 2004 showed promising results and began to elucidate some of the mechanisms in the brain (relating to neurotransmitter activity and the reduction of protein tangles) that contributed to its positive effect. Now, a new trial in the European Journal of Neurology (those Europeans, always messing around with herbs...) confirms the previous results and lends more credence to ginkgo as a good treament for slowing the progress of Alzheimer's disease. It also reinforces the idea that ginkgo has the effect of increasing ACh (acetylcholine, an important neurotransmitter in the brain and body) sensitivity, and is much better tolerated than the prescription drugs that are currently used.