UNDER the title "The Borderland of Epilepsy," Gowers1 in 1907 focused attention on a group of patients with fainting spells, vagal and vasovagal attacks, vertigo and similar episodic disturbances. He emphasized the difficulty in many instances of deciding whether or not the spells were epileptic and warned that even when such episodes are accompanied with loss of consciousness "a single attack of this character does not justify a diagnosis of epilepsy with all its attendant concern and anxiety."
The introduction of electroencephalography has provided an important new technic in the investigation of epileptic disorders, and the method helps to differentiate episodic phenomena that are primarily cerebral in origin from those which are extracerebral.
It has been demonstrated by Levin, Katz and Greenblatt2 that for patients subject to typical "fainting spells" the incidence of electroencephalographic abnormalities is about the same as that for normal controls. On the other hand,
KERSHMAN J. "THE BORDERLAND OF EPILEPSY"A Reconsideration. Arch NeurPsych. 1949;62(5):551-559. doi:10.1001/archneurpsyc.1949.02310170026002