Unless you really know what you are doing, this is best left alone. Four a start, if you any sort of power supply connected to the part on your body, it should be a medical grade one. The leakage current must be very low. Then you need to be able to check this. You would be safer if the parts connected to your body are battery powered. Whatever you do, don't run any electronics from a mains supply to your head unless you really know what you are doing, and have the equipment to check it.
I just looked at
**broken link removed**
and it looks seriously flawed to me. It looks like they are using a PC with a microcontroller with references to things like "hot melt glue" and "soldering iron". Clearly this is not a professional, and you are best leaving it alone. For what it is worth, I have a Ph.D. in Medical Physics, so I suspect I know more about this sort of thing than the person writing the article telling you to use hot melt glue.
Dr. David Kirkby B.Sc. M.Sc Ph.D MIET C.Eng.