ABNORMAL PROJECTION OF CORTICOSPINAL TRACTS IN A PATIENT WITH CONGENITAL MIRROR MOVEMENTS

A 31 year-old woman with familial congenital mirror movements not asso ciated with other neurological defects underwent a detailed neurophysi ological evaluation including: voluntary electromyographic activity re corded from upper limbs in response to acoustic stimuli, motor evoked potentials from the thenar muscles to focal transcranial magnetic stim ulation, F waves from upper extremities, scalp somatosensory evoked po tentials and long-latency responses from thenar muscles to electric st imulation of the median nerve. The results were consistent with the pr esence of fast-conducting pathways connecting each hand motor cortex w ith both contra- and ipsilateral spinal motoneurones.