Modulation techniques in transcranial electrical brain stimulation

Noninvasive transcranial electrical stimulation of the brain is accepted as a simple, useful, and affordable method in neurophysiology research, cognitive neuroscience and treatment of neurological diseases. Current flowing through the brain generates an electric field that is enough to increase or decrease the excitability of the tissue. We have decided to improve and test applications of this method and started a research program for this purpose. In order to be able to test our hypothesis about the improvement of the method through novel modulation techniques, we have designed modulated transcranial direct current stimulators. We have used those devices in our research at makeLab to question the effectiveness of modulation techniques in impulsiveness, memory research, pain and perception, and epilepsy treatment. Original contribution of our research activities to the scientific literature is to use the amplitude modulated direct current for transcranial brain stimulation, to design and build devices for that purpose, developing and building a sham generation and coding-decoding system in order to improve the statistical reliability of analysis and experimental setup. In addition to the positive results in neurophysiology and clinical neurology research, we have ended with failed experiments and questionable results which we shared with the scientific community. We demonstrated the differences of modulated transcranial electrical stimulation applications with reference to the similar research reported in the scientific literature and concluded with a suggestion that requires testing of transcranial stimulation techniques with improved experimental protocols, provable hypothesis and wider participation.