The ethics of brain boosting - University of Oxford: Recent research in Oxford and elsewhere has shown that one type of brain stimulation in particular, called transcranial direct current stimulation or TDCS, can be used to improve language and maths abilities, memory, problem solving, attention, even movement.
Critically, this is not just helping to restore function in those with impaired abilities. TDCS can be used to enhance healthy people’s mental capacities. Indeed, most of the research so far has been carried out in healthy adults.
TDCS uses electrodes placed on the outside of the head to pass tiny currents across regions of the brain for 20 minutes or so. The currents of 1–2 mA make it easier for neurons in these brain regions to fire. It is thought that this enhances the making and strengthening of connections involved in learning and memory.