Schiffer, Randolph B.; Rao, Stephen M.; Fogel, Barry S. (2003). Neuropsychiatry: A Comprehensive Textbook, Second Edition. Lippincott Williams & Wilkins. pp. 948. ISBN0-7817-2655-7. «Charcot, however, was the first to identify the involuntary "impulsive" ideas, such as doubting mania, double checking, touching, and arithmomania (an obsession with counting and numbers), as part of GTS and to link them to the impulsive movements.»