Neural Inhibitor

A device shaped like a steel circlet which is placed around the head of a person with psionic mental abilities (telepathy, telekinesis, etc.). The device emits high-frequency radio waves that disrupt the delta wave capabilities of the wearer's brain, thus dampening any psionic abilities. Neural inhibitors have been known to be capable of being reprogrammed to reverse the effect and actually create a barrier for the wearer against any telepathic infiltration or attack.

In 'X-Men 2: United', William Stryker placed a neural inhibitor on the telepathic Professor X's head in order to interrogate and incarcerate him without retaliation.