Here's a great article on New Scientist which shows how some drugs intended for one thing may unexpectedly be good for something else. In this case, the sedative zolpidem (marketed as Ambien) has been found to help patients with brain damage due to oxygen deprivation regain crucial functionality. Although they still don't know how or why it works, there are some suggestions:
PET scans, which measure the blood flow and metabolic rate in different areas of the brain, showed the drug boosted activity in brain regions which showed no activity without the drug. The team thinks zolpidem turned on specific "loops" of circuitry in the brain associated with motivation, movement and speech.
In other words, Ambien somehow helps activate silent areas of the brain far removed from the actual damage area, implying that communication gaps in neural network circuitry may be somehow re-routed or re-activated if the proper chemical switches are applied. Also from the article:
[The presence of silent areas] may be due to depletion of the neurotransmitter GABA. Zolpidem stimulates GABA receptors, which are active in different parts of the brain, not just the circuitry that triggers sleep.
Interesting theory, but obviously more research should be done on this drug. Ambien has been shown to have a variety of bizarre side effects, here is one more. This study shows that there may be inhibitory or suppressive mechanisms within the brain that stop specific network chatter when one particular area of the brain becomes damaged, and if those silent areas are disinhibited by something like Ambien, functionality lost due to brain damage can be coaxed into switching back on. Amazing science at work people.
