Electrical Brain Stimulation Beats Caffeine

Military analysts spend hours poring over images to identify enemy targets.

Their task isn’t suited to automation, so that’s why it’s really important to find out if there are ways to help them focus for a longer period of time.

Research is esssential

Scientists at the Air Force Research Laboratory in New Carlisle, Ohio, U.S., have conducted research on 18- to 42-year old men and women on active duty.

Military staff put to the test

The researchers kept 30 of these military analysts awake, and tested their reaction time every two hours. The test ran for a total of 30 hours.

At 4am, when people’s cognitive performance is usually at its worst, the researchers gave the subjects two things: a gum that contained caffeine, and electrical brain stimulation.

However, these 30 people were divided in 3 groups:

• The first group were given the gums with caffeine, but received fake brain stimulation (it’s difficult for people to tell if it’s real or not, because the current is hardly perceivable).
• The participants in the second group were asked to chew gum, but they didn’t know these had no caffeine in them. The electrical brain stimulation they received however was real: for 30 minutes the left side of their pre-frontal cortex was electrically stimulated.
• And lastly, the third group did not receive any stimulants at all – no caffeine-containing gum, and no real electrical stimulation either. The participants didn’t know this however. So they effectively received a placebo.

Transcranial Direct Current Stimulation (tDCS)

The brain stimulation used was a procedure called transcranial direct current stimulation (tDCS), whereby a low current is delivered directly to the brain by electrodes that are placed on the scalp.

The current is extremely mild and barely noticeable to the user. It’s even possible to carry out tasks while undergoing transcranial stimulation.

The results

Both groups, the “caffeine” group and the “brain stimulation” group, got a boost in their cognitive performance and ability to focus.

But the electrical brain stimulation improved performance twice as much as the caffeine.

The third group did not show an increase.

Sustained benefits

At 8 am, four hours after the boost, the group who received the brain stimulation scored 60% on a vigilance test.

In comparison, the performance of the other groups, the group with caffeine plus fake electrical stimulation, and the test group with only placebo’s, declined rapidly.

They both scored 30%.

Conclusion

So, caffeine had a rapid cognitive effect, but it wore off after 2 hrs.

Half an hour of brain stimulation on sleep-deprived military staff improved their performance twice as much as caffeine. And the effect lasted three times as long.

Andy McKinley, who led the research, commented:

“I think the reason we’re getting these long-term effects is they are making some longer-lasting changes to the neural connections.”

Read the full article here

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