Neuroscientists at Imperial College London in the UK have proven the benefits of electrical brain stimulation for working memory. The researchers' article was published in the journal eLife.
The researchers used transcranial electrical stimulation (TES) therapy, in which the brain is exposed to a non-invasive current at low voltage. The electrodes were applied to the head so that the procedure involved the frontal medial gyrus and the inferior parietal lobe. These areas were chosen because they are involved in the formation of working memory.
The experiments involved 31 volunteers. Scientists stimulated their brains so that slightly out of sync or synchronized theta rhythms appeared in the zones of working memory. At the same time, people were performing certain tasks. First, they were shown a series of rapidly alternating images with arrows pointing to the right or left on the screen. The subjects had to correctly indicate where each arrow was directed by pressing the corresponding button. In other types of tasks, the participants were shown different sequences of numbers several times, and the volunteers had to remember which ones were repeated.
Scientists have found that synchronizing the brainwaves allows people to perform better at tasks. At the same time, functional MRI scans showed that the brain areas stimulated by the current increased their activity.
