Transcranial magnetic stimulation in patients with Rett syndrome: preliminary results.

Transcranial magnetic stimulation was used to investigate Rett patients (n = 31, age 2-38 years). The results were compared to healthy control persons (n = 112, age 1 month-35 years). The peripheral conduction time showed no difference between the patients and control persons. The mean central conduction time, however, was shorter in the younger patients with Rett syndrome, and this is particularly evident in the youngest. This phenomenon could be interpreted as cortical and/or spinal hyperexcitability which occurs during the early stages of Rett syndrome.