The lead author of this research study, Dr. Bullard, maintains that this procedure allows for altered brain-wave activity and accelerated learning. She examined MRI brains scans and magnetoencephalography (MEG) and found physical changes to confirm this. Apparently, these tests showed that TDCS gave a six-times baseline boost to the amplitude of a single brain wave.
This boost was not seen when a placebo TDCS was used and this mock wave was ineffective in exciting brain tissue. Basically the effect will persist long after the TDCS is stopped, up to almost an hour of time. These results tell us that TDCS increases the cerebral cortex excitability, therefore increasing arousal, improving sensory input response, and speeding up information processing.
Surprisingly, the MRI brain tests revealed actual structural changes in the brain five days after the TDCS was done. The neurons of the cerebral cortex connect with each other to form circuits by way of nerve fiber bundles (axons) that are buried deep below the surface of the brain. These fiber bundles are more robust and highly organized after the TDCS. None of this is noted on the side of the brain that is not stimulated by this procedure.