According to researchers at the University of Utah School of Medicine, some of old age’s mental slowdown may be reversible with doses of a neurotransmitter called GABA:
Macaque monkeys, with an age equivalent to 90-years in humans, were not as sharp as their younger counterparts in visual tests despite having perfect eyesight. But when they were given drugs to increase levels of GABA in the brain they improved vastly, say the team.
Delivering GABA calms the neurons down and they become more selective, says neuroscientist Audie Leventhal, at the University of Utah School of Medicine, who led the study. “They look the same as they did 20 years ago,” he says. […]
However, this somewhat glib portion was probably my favorite part of the article:
“It is counterintuitive to say that in order to make Grandpa faster, slow down his brain. Nobody was really thinking about giving tranquillisers to an 85-year-old to perk him up — which is the implication of the study,” he says. […]