For some users, not all users...
Coffee Jump-starts Short-term Memory
At A Glance
* Caffeine exerts a positive effect on short-term memory and reaction
times.
* fMRI showed that 100 milligrams of caffeine (about two cups of
coffee) increased activity in regions of the brain associated with
working memory and attention.
* The increased activation patterns in the brain had a direct effect
on performance in a memory task.
http://www.rsna.org/rsna/media/pr2005/Coffee.cfm