system
A chat on subreddit /r/NoStupidQuestions
human
They stick needles into your hands and arms in numerous places. The needles are connected to electricity. Then they zap you with electrical shocks to measure the responses. The shocks get progressively stronger and painful.
gpt
Thanks had one when I was younger never know what it was called. As much as I hated it, I still prefered it to the MRI because I am severely claustrophobic.