Cortex neuromodulation is promising approach for treatment of some neurological conditions, especially neuropathic pain and Parkinson's disease. Effects of non-invasive cortical stimulation are short lived; transcranial direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS) may be useful to assess the suitability for invasive cortical stimulation. Direct cortical stimulation (DCS) is the method able to provide long-lasting effects in treatment of neuropathic pain and some symptoms of Parkinson's disease through the use of totally implantable systems that ensure a chronic stimulation.
Lavano, A., Guzzi, G., & Chirchiglia, D. (2018). Cortical neuromodulation for neuropathic pain and Parkinson disease: Where are we? Neurologia i Neurochirurgia Polska, 52(1), 75–78. https://doi.org/10.1016/j.pjnns.2017.11.001