--although it may feel the same.

Evoked potential testing also involves stringing up people with electrical wires, but it is used to determine if there is demyelination/signal delay or change in the sensory processing that goes on between the eyes (visual evoked potential or VEP), ears (auditory evoked potential or AEP) or skin (somatosensory evoked potential or SSEP) and the brain. You'd be hooked up to brain electrodes and asked to watch stimuli, listen to stimuli, or feel stimuli and the testing person will be watching your brain waves on an oscilloscope to see reaction/times and patterns.

These tests are often used when central nervous system conditions are suspected but not readily apperceptible by MRI or other imaging--a lot of people have had MS diagnoses confirmed this way, for example.

The Wikipedia article is actually a pretty good explanation of these:

http://en.wikipedia.org/wiki/Evoked_potential