Ginkgo and Memory
There are several studies that have found that Ginkgo, either on its own or combined with other herbs, has a positive effect on memory.
A 2008 double-blind study of elderly patients with mild to moderate memory impairment stated that the results suggest that “Ginkgo biloba extract had a beneficial effect on cognitive function in this group of patients. Performance on the Digit Copying sub-test of the Kendrick battery was significantly improved at both 12 and 24 weeks, while the median speed of response on a computerized version of a classification task also showed a significant superiority over placebo at 24 weeks”
A study published in Psychopharmacology (2000) by Wesnes et al , using a combination of ginkgo and panax ginseng, found that it significantly improved an Index of Memory Quality, “This effect represented an average improvement of 7.5% and reflected improvements to a number of different aspects of memory, including working and long-term memory.”
A 1999 study looking at the benefits of Ginkgo for memory at varying dose levels found that the most beneficial level was at a lower dose (120mg daily). The authors stated “The results confirm that the effects of GBE extract on aspects of cognition in asymptomatic volunteers are more pronounced for memory, particularly working memory. They also show that these effects may be dose dependent though not in a linear dose related manner, and that GBE 120 mg produces the most evident effects of the doses examined. Additionally, the results suggest that the cognitive enhancing effects of GBE are more likely to be apparent in individuals aged 50–59 years”
A 2001 study by Stough et al conducted a randomized, double-blind, placebo-controlled clinical trial in which 61 healthy participants were administered a battery of validated neuropsychological tests before and after treatment. Statistical analysis indicated significant improvements in speed of information processing working memory and executive processing attributable to the Ginkgo biloba extract
Not all studies show a clear benefit. A 2002 randomised control trial study by Solomon et al found that “ginkgo did not facilitate performance on standard neuropsychological tests of learning, memory, attention, and concentration or naming and verbal fluency in elderly adults without cognitive impairment.”
Ginkgo and Alzheimer’s Disease
A 1998 review by Oken et al published in the Neurological Review analysed a number of studies that had investigated the use of ginkgo biloba to help with the effects of Alzheimer’s Disease. It found “there is a small but significant effect of 3- to 6-month treatment with 120 to 240 mg of G biloba extract on objective measures of cognitive function in AD”.
Ginkgo and Attention Deficit Disorder
A pilot study by Neiderhofer in 2009 found that ”during Ginkgo biloba treatment, the patients' mean scores improved significantly overall and in hyperactivity, inattention, and immaturity factors. This preliminary study indicates that Ginkgo biloba might be a beneficial and useful treatment of ADD, with minimal side effects”