A number of studies show ginkgo significantly improves alertness, mood, memory, headaches, vertigo and intellectual capacity. A recent study found that ginkgo may improve the memory of Alzheimer's disease patients. The herb has also been shown to protect cell membranes in the brain and other tissues against free radical damage. Ginseng is another valuable herb for mental clarity and memory enhancement. Known as the longevity herb, ginseng is used regularly by elderly Chinese men and women to slow the aging process.
Tests show ginseng increases learning and memory in animals.
It also appears to stimulate the immune system. One Soviet researcher has studied ginseng for nearly 30 years. Regular use of bilberry is also thought to help prevent or treat other eye diseases such as macular degeneration, diabetic retinopathy and cataracts. The herb contains powerful substances known as anthocyanosides that have a special attraction to the retina. They have been shown to strengthen blood vessel walls and reduce inflammation.