Electric hat zaps brain with mild electrical currents to make people smarter

Electric hat zaps brain with mild electrical currents to make people smarter

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Wanna be smarter? Try the new electric hat. From students cramming for exams to adults wishing they had the answer to a difficult question, most people would love a quick way of becoming smarter. And now scientists have created a real ‘thinking cap’ that helps people solve problems more quickly and could one day help us learn new and difficult material more easily. U.S. psychologists have managed to manipulate our ability to learn using a mild electrical current to the brain, which can make people learn from their mistakes more effectively – or equally make them more prone to mishaps and confusion. Previous research has shown that the medial-frontal cortex - which is the part of the brain responsible for spotting mistakes - emits a spike of negative voltage within milliseconds of us recognising that we have done something incorrectly. But it didn’t explain why. Psychologists Robert Reinhart and Professor Geoffrey Woodman at Vanderbilt University in Nashville, Tennessee, explored the function of the brainwaves.

Mr Reinhart, a PhD candidate, said: ‘We wanted to reach into your brain and causally control your inner critic.’ They came up with a headband with two electrodes attached to the check and crown of a person’s head, to which they applied 20 minutes of transcranial direct current stimulation (tDCS) to each willing participant in the experiment. In tDCS, a mild direct current travels from the anodal electrode, through the skin, muscle, bones and brain and out through the corresponding cathodal electrode to complete the circuit, according to the study, which is published in the Journal of Neuroscience.

‘It’s one of the safest ways to noninvasively stimulate the brain,’ Mr Reinhart said, before explaining that the subjects only reported a few seconds of tingling or itching at the beginning of each stimulation session.

Each participant took part in three sessions: one where the current was travelling from the electrode on the crown of the head to the one on the cheek, one where it was travelling in the opposite direction and another where there was no stimulation to the brain, but the subjects felt a ‘sham’ tingling sensation. Participants were unable to tell the difference between the three conditions. After 20 minutes of stimulation, subjects were given a learning task that involved working out by trial and error which buttons on a game controller corresponded to specific colours displayed on a monitor. For added difficulty, participants had just one second to respond correctly, providing many chances to make errors and therefore opportunities for the medial-frontal cortex to fire. The researchers measured the electrical brain activity of each participant, which allowed them to watch as the brain changed at the very moment participants were making mistakes and most importantly, allowed them to determine how these brain activities changed under the influence of electrical stimulation. When anodal current (travelling from the electrode on the crown of the head to the cheek) was applied to the ‘thinking hat’ the spike was almost twice as large on average. Consequently, people made fewer errors and learned from their mistakes more quickly than they did without any electrical stimulation. When cathodal current (travelling in the opposite direction from the electrode on the cheek to the crown) was applied, the researchers observed the opposite result. The spike was significantly smaller and the subjects made more errors and took longer to learn the task, effectively becoming more stupid.

‘So when we up-regulate that process, we can make you more cautious, less error-prone, more adaptable to new or changing situations, which is pretty extraordinary,’ Mr Reinhart said. The effect was not noticeable to the subjects because their error rates only varied about four percent either way and their behaviour adjusted by a matter of only 20 milliseconds, but they were plain to see on the EEG, or electroencephalogram that records the brain’s electrical activity.

‘This success rate is far better than that observed in studies of pharmaceuticals or other types of psychological therapy,’ said Professor Woodman. The researchers found that the effects of a 20 minute stimulation lasted about five hours and made participants marginally better or worse in other tasks. As well as improving learning, the findings of the experiment could one day be used to treat conditions like schizophrenia and ADHD, which are associated with performance-monitoring deficits.

Published by Dailymail