A study by the Pablo Olavide University of Seville has shown thatapplying weak currents through the skull modifies learning of simple motor tasks, accelerating or interrupting said process depending on the polarity of the applied current. The results are published in the journalPNAS.
During the last decade, various publications have shown how the use of low intensity currents applied to electrodes located on the skin of the head can modify the activity of brain neurons located under these electrodes. This technique, calledtDCS(of EnglishTranscranial Direct Current Stimulation), has generated great interest in the scientific and medical community, which sees in it a simple, inexpensive and painless way to treat somenervous system pathologies such as depression, epilepsy, chronic pain, Parkinson’s, or stroke. However, there is great ignorance about the way in which these currents modify the activity of neurons in the short and long term.
In the new article, the researchers show how the application of weak currents through the skull is able tomodify the synaptic mechanisms involved in associative learning. The experiments show that the application of this type of currents in the sensory cortex allows to increase or decrease the degree of perception of the subject before the same stimulus, influencing the learning of new motor tasks.
On the other hand, the authors have shown in their study that the changes in neuronal synaptic activity induced by prolonged electrical stimulation are mediated byneuronal receptors for adenosine, which can have an important impact on the clinical application of this technique.
