at least, in mice it does:
http://www.medscape.com/viewarticle/709493?src=mpnews&spon=12&uac=89474MT

http://www.wired.com/medtech/drugs/magazine/17-09/ff_placebo_effect?currentPage=all

AWESOME article. Nutshell: research has show that the biochemistry of the placebo response is due to anticipation-activated opioids and dopamine. Effects of opioids include pain relief, heart rate and breathing modulation. Effects of dopamine include improved motor function in Parkinson's. Both contribute to elevated mood, sharpened cognitive ability, decreased digestive disorders and insomnia, and lower levels of insulin and cortisol. But the whole article is well worth reading. ( Here's the text. I would take notes but I admire this guy's prose too much to chop it up. This article matters. )

The incidence of dementia is increasing even faster than the incidence of cancer!!
This won't help one bit.

Headline:
PTSD Linked to 2-fold Increased Risk for Dementia in Veterans
Caroline Cassels
( from Medscape, on the first study re this question )

What sorts of dementia may be reversible?
( part 4 Miller notes on dementias: Parkinson's dz, demyelinating dz, multi-infarct, Alzheimer's )

Just started reading Deep Survival, and already it has grabbed me. The author Laurence Gonzales knows about the brain, about memory and emotion and the ways that we humans operate. I don't entirely agree with his presentation of brain function--it is a little simplistic--but overall it is a useful framework. I'm on page 67 at the moment, and there are a couple of quotes I'd like to record here:
( quotes and ruminations )