Use of illicit amphetamines is associated with long-lasting changes in hand circuitry and control.

Objective: The study aim was to determine if use of illicit amphetamines or ecstasy is associated with abnormal excitability of the corticomotoneuronal pathway and manipulation of novel objects with the hand.

Methods: Three groups of adults aged 18-50 years were investigated: individuals with a history of illicit amphetamine use, individuals with a history of ecstasy use but minimal use of other stimulants, and non-drug users. Transcranial magnetic stimulation was delivered to the motor cortex and the electromyographic response (motor evoked potential; MEP) was recorded from a contralateral hand muscle.