Not sure how accurate this statement is, but it’s a good way to think of it.
“tDCS changes the voltage across neurons and can make them more or less likely to fire.”
Interesting… use TMS to disrupt the function (for discovery) and tDCS to enhance it!

His team “short-circuited” this area using transcranial magnetic stimulation (TMS) – a stream of magnetic pulses which temporarily disables a targeted area of the brain. The result, they found, was that people’s ability to perform numerical tasks fell. In fact, their performance resembled people with dyscalculia, who have difficulty comprehending mathematics.

Now they have done the reverse, and improved the brain’s arithmetical abilities. To do this the team applied transcranial direct current stimulation (tDCS), a way of enhancing brain activity using an electric current, to the right parietal cortex while simultaneously using the opposite current to subdue activity in the left parietal cortex.

via Electrical brain stimulation improves math skills | The Santos Republic.