I am new to tDCS. It seems to me that most of the guidelines on cathode/anode placement assume that you are measuring to find the “vertex” on your head, then finding the other focal points in reference to this point. The actual measuring and plotting of these points seems like it would be difficult to do alone. I am making an assumption that a significant number of people are just “winging it”, and approximating their placements.
I am curious to how important an “exact” placement is. I do not know much about electrodes, or how electricity tends to travel through the tissues and bone into the brain. I am saying this from ignorance, yet it seems like it would often be difficult to have pinpoint accuracy on an area. It seems that there would be some errant electrical charge that would flood to other areas of the brain.
Since most people seem to be getting positive results anyway, it is it the case that it is okay to proceed without exactitude (yet with as much care as possible)?