IN AN era of increasing pressures for cost-effective diagnoses, there are considerable incentives to integrate procedures, which may trigger a paroxysmal event when no spontaneous episodes are occurring. Provocative tests (PT) for the diagnosis of nonepileptic seizures (NES) have included several techniques: intravenous saline, a tuning fork applied to the forehead, an alcohol pad placed on the skin or the carotid artery, psychiatric interview, hypnosis, and the use of anhydrous ammonia.1- 14 Hyperventilation, photic stimulation, and obstruction of the airway have also been used to provoke NES in patients. The most commonly employed technique is the use of intravenous saline in combination with suggestion.
John R. Gates. Provocative Testing Should Not Be Used for Nonepileptic Seizures. Arch Neurol. 2001;58(12):2065–2066. doi:10.1001/archneur.58.12.2065