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Jean-Martin Charcot (November 29, 1825 - August 16, 1893), a French neurologist who has been called "the father of French neurology" and one of the world's pioneers of neurology. Charcot provided the following account of tuning fork trials: The patient was seated over the sounding box of a strong tuning fork, made of bell metal, vibrating 64 times in a second. After a few moments the patients become cataleptic, the eyes remain open, they appear absorbed, are no longer conscious of what passes around them, and their limbs preserve the different attitudes which have been given them. If the vibrations of the tuning fork are abruptly arrested, the laryngeal sound is heard immediately, the limbs fall into a state of resolution and the patients at once become lethargic. Catalepsy is a nervous condition characterized by muscular rigidity and fixity of posture regardless of external stimuli, as well as decreased sensitivity to pain. No artist credited, undated.
