Star Trek: Deep Space Nine1993

Elim Garak:
My implant was given to me by Enabran Tain himself, the head of the Obsidian Order. If I was ever tortured, it was designed to stimulate the pleasure centers of my brain, to trigger the production of vast amounts of natural endorphins. I do hope you appreciate the irony, Doctor. The whole purpose of the implant was to make me immune to pain.

Dr. Julian Bashir:
What caused it to malfunction?

Elim Garak:
It was never meant for continuous use.

Dr. Julian Bashir:
Continuous use? What do you mean?

Elim Garak:
Living on this station is torture for me, Doctor. The temperature is always too cold, the lights always too bright, every Bajoran on the station looks at me with loathing and contempt. So one day, I decided I couldn't live with it anymore. And I took the pain away.