Transcranial magnetic stimulation was used to investigate the effect of the psychostimulant drug methylphenidate (MPH) on motor cortex excitability in healthy adults (n = 12) in a placebo-controlled, crossover design study. MPH caused an enhancement of intracortical inhibition as well as intracortical facilitation. Enhancement of both of these TMS parameters was unexpected and suggests that MPH exerts its action on the motor cortex not only through the dopaminergic neurotransmitter system.
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Dr. Janbernd Kirschner (current address)
Children’s Hospital of Philadelphia
512 D Abramson Research Center
34th St and Civic Center Blvd
Philadelphia, PA 19104
USA
Email: Kirschnerj@email.chop.edu
Phone: (001)267-4265164
Fax: (001)215-5903709
