They found that participants who received electrical stimulation of the anterior temporal lobes were three times as likely to reach the fresh insight necessary to solve a difficult, unfamiliar arithmetic test than those in the control group.
"You wouldn't use this to study or to help your memory," said Allan Snyder, director of the University of Sydney's Centre for the Mind. "You would use this if you wanted to look at a problem anew.”
Looking outside the box
Snyder said the device, which consists of two conductors fastened to the head by a rubber strap, worked by suppressing the left side of the brain, associated with knowledge, and stimulating the right side, linked to creativity.
"If you wanted to look at the world, just briefly, with a child's view, if you wanted to look outside the box,” he said about the research published in open-access journal PLoS ONE.
According to Snyder the goal was to suppress mental templates gathered through life experiences to help users see problems and situations as they really appear, rather than through the prism of earlier knowledge.
Fighting the creative bottleneck
Snyder added that the work was inspired by accident victims who experienced a sudden surge in creativity after damaging the left side of their brains.
"We know that from certain types of brain damage and abnormalities or injuries, people who suddenly have damage to the left temporal lobe will burst out in the arts or other types of creative activities," he said.
According to the authors, our propensity to rigidly apply strategies and insights that have had previous success is a major bottleneck to making creative leaps in solving new problems. There is normally a cognitive tradeoff between the necessity of being fast at the familiar on one hand and being receptive to novelty on the other.
Moderating the trade-off
The study argues that we can modulate this trade-off to our advantage by applying transcranial direct current stimulation (tDCS) - a safe, non-invasive technique that temporarily increases or decreases excitability of populations of neurons.
In particular, tDCS can be used to manipulate the competition between the left and right hemisphere by inhibiting and/or disinhibiting certain networks.
The author’s findings are consistent with evidence that the right anterior temporal lobe is associated with insight or novel meaning and that inhibition of the left anterior temporal lobe can induce a cognitive style that is less top-down, less influenced by preconceptions.
An unfiltered view of the world
Snyder said the device had been in use by scientists for a decade, but this was the first study into how current passing through the brain could amplify insight. He said the ‘thinking cap’ had potential applications in the arts and problem-solving, although the science remained in its infancy.
While further studies involving brain stimulation in combination with neuroimaging are needed to elucidate the exact mechanisms leading to insight, Snyder and co-author Richard Chi, also from the Centre for the Mind, can imagine a future when non-invasive brain stimulation is briefly employed for solving problems that have evaded traditional cognitive approaches.
"The dream is that one day we may be able to stimulate the brain in a particular way to give you, just momentarily, an unfiltered view of the world," said Snyder.