Does Electrical Brain Stimulation Work?
A few years ago in the Brainpower Newsletter I reported on
a study done at the U.S. National Institute of Neurological Disorders
and Stroke. More than 100 volunteers had to recall as many words
that begin with a particular letter as possible. When a 2-milliamp
current (less than a small battery) was passed through electrodes
on the volunteers' foreheads, the volunteers came up with an
average of 20 percent more words.
Other than some irritation from the electrodes, no other side
effects were noted from this electrical brain stimulation. It
wasn't clear why this works, but scientists suspected that the
current allowed cells in the prefrontal cortex, the brain region
associated with verbal memory, to transmit signals more easily.
Using electricity to modify the brain isn't all that new, by
the way. Historians think that almost two thousand years ago
Greek physicians had patients apply a live torpedo fish, which
is a type of electric ray, to the forehead as a cure for headaches.
Now, as recently reported by the Reuter's new's service (November
2010), a new study by neuroscientists at Britain's Oxford University
has found that electrical brain stimulation can enhance a person's
maths ability. Amazingly, the improved abilities were not limited
to the time the current was on. In fact, subjects were found
to have better math skills six months later.
For the study, volunteers (young adults) memorized symbols
that represented different numerical values. Then they had to
do a series of math puzzles based on the symbols. Speed and accuracy
were measured. During each of the six days of the tests, subjects
had either a placebo or electrical stimulation across the parietal
lobe for 20 minutes. This is an area of the brain that is important
for doing mathematical work.
A tingling sensation was noticed by those who received the
electric brain stimulation, and that was generally felt for only
the first 20 seconds or so. No other side effects were noted
(but don't try this on your own). Only a one milliamp electrical
stimulus was used in this study. Interestingly, those who had
the current passed from right to left parietal lobes had the
biggest boost in performance (some had the current passed from
left to right).
After a follow up six months later - which showed that the
group which received the electrical brain stimulation still did
better in the math tests - the study was reported in the journal
Current Biology. Other scientists have suggested that being able
to stimulate certain parts of the brain in this way might be
useful for treating a range of psychiatric and neurological problems
ranging from visual impairments following stroke to compulsive
Since that study, other scientists found that using electrodes
to electrically stimulate areas deep within the brain may help
patients with severe obsessive compulsive disorder, especially
those who do not respond to other treatments. If there are more
studies on brain stimulation - as I'm sure there will be - I'll
report on them in the Brainpower Newsletter and on this site.
Source: Electric brain stimulation can improve math skills.