hundred milligrams of caffeine, the equivalent of two cups of coffee,
can increase activity in the part of your brain that is responsible for
short-term memory. A study showed improved performance on a memory test as a
The functions of this region of the brain also include prioritizing
information efficiently, planning new tasks, and dealing with stored
Memory and Attention Brain Regions
Functional magnetic resonance imaging (fMRI) on a sample of 15 men showed
that caffeine increased activity in a brain region in the frontal lobe (part
of the working memory network) and in the anterior cingulate cortex, which
controls attention. When the men were given a placebo instead, there was no
increase in activity in these areas of the brain.
When given caffeine, they also demonstrated improved reaction time on a
test involving a randomized sequence of capital letters, in which they had to
decide, as quickly as possible, whether the current letter was the same as or
different from the letter presented two letters previously.
The mechanism by which the caffeine acts on the brain is largely unknown,
but it may be related to the way the chemical reacts with the brain's small
blood vessels and nerve cells.