In the fictional Star Trek universe, the Vulcan nerve pinch is a technique used mainly by Vulcans to render unconsciousness by pinching a pressure point at the base of the victim’s neck.
Leonard Nimoy, who portrayed the Vulcan science officer Spock, conceived the maneuver in the early days of the original Star Trek series. The script for “The Enemy Within” stated that Spock "kayoes" Captain Kirk’s duplicate, but Nimoy—who opposed the Vietnam War and supported Eugene McCarthy—felt that such a brutal action would be undignified for a Vulcan. He therefore invented an alternative by suggesting that Vulcans have the ability to project telepathic energy from their fingertips similar to "the Vulcan Mind Meld", which, if applied to a nerve cluster correctly, could render a human unconscious. Allegedly, the director of the episode didn't understand the idea when Nimoy explained it to him, but William Shatner understood immediately and reacted in exactly the way Nimoy had hoped when they executed the move during filming, explaining that it would be similar to "feeling an electrical charge." From then on, the pinch was referred to as the "FSNP", for "Famous Spock Nerve Pinch" in Star Trek’s scripts.
Since Spock, various other characters in the Star Trek spin-offs have used the technique; however, the fact that some of these have included non-Vulcan characters creates some confusion about the above explanation as to how the nerve pinch is achieved – likely among writers and production-staff, since in the episode "The Omega Glory" Kirk tells Spock "Pity you can't teach me that" (i.e. the Vulcan Nerve Pinch), and Spock replies "I have tried, Captain." The first non-Vulcan was the android Data, followed by the Changeling Odo,Voyager’s holographic Doctor, and the humans Jean-Luc Picard,Seven of Nine, and Jonathan Archer (though Archer was carrying the katra of the ancient Vulcan Surak at the time). In the prequel series Star Trek: Enterprise T'Pol uses it in the 4th episode of the first season ("Strange New World") on Travis Mayweather, to calm him down. Other examples of its use in that series include incapacitating Dr. Phlox before he can lobotomize Travis Mayweather in the 2nd season episode "Singularity", and again in the 3rd season episode "Carpenter Street", on the kidnapper Loomis to stop him escaping from his apartment.