Cerebral implant

A cerebral implant is when somebody sticks something in your noggin. Generally its an electronic device of some sort, the purpose of which may vary. Sometimes its may be used for something benign such as monitoring a patient's brain wave patterns. In most cases however, its usually equipped with some sort of explosive device. At the discretion of some merciless bastard, a mild headache can turn into a five-alarm KABLOOEY! In other cases, cerebral implants may be used as a form of behavior modification.

On Buffy the Vampire Slayer, a college-based militia group called The Initiative implanted the vampire Spike with a device that prevented him from committing any acts of violence against a human being. Any attempt to do so would result in massive trauma. The activation of the implant was contingent up on whether the patient genuinely believed he or she could cause damage to a target.