News Editor: Renato M.E. Sabbatini, PhD
Drugs Which Improve Memory
Acethilcholine and glutamate are some neurotransmitters which plays important roles in memory.
A new study conducted at the National Institute on Aging (NIA), has show the drug physostigmine to aid and improve the performance of everyday working memory when administered to people by infusion in laboratory tests.
Researchers used positron emission tomography (PET) to find the areas of the human brain that are activated during working memory, and to determine how activity in those regions is modified by a working memory enhancing drug. Working memory is the process which temporarily holds information such as a phone number until a person gets to a phone to dial the number.
Physostigmine is a short-acting drug that enhances levels of a substance (acetylcholine) between neurons in the brain. The drug improves efficiency and reduces the effort needed to perform working memory tasks while altering the activity of some of the brain regions activated by this memory task.
In the study, the control volunteers received only saline during their brain scans whereas the experimental volunteers received physostigmine. Drug levels were checked after each scan by taking blood samples. PET scan results were then evaluated to identify those areas of the brain that were active during working memory to determine how the two conditions differed, both with and without physostigmine.
The results of the trials showed that enhancing acetylcholine transmission with physostigmine resulted in improved working memory performance and altered neural activity in a cortical region known to be important to this memory task.
Pietro Pietrini, M.D., NIA scientist and another author of the study, points out that the drug may enhance efficiency during the processing of information by focusing attention on the task at hand or it could help minimize the effects of distracting stimuli. Either way, a more efficient working memory could be a great advantage for Alzheimer's disease patients and other memory-impaired people.
Proceedings of the National Academy of Sciences 94: 6512-6516, 1997