MEG evaluation of Parkinson's diseased patients after external magnetic stimulation.

Magnetoencephalographic (MEG) recordings of Parkinson's diseased (PD) patients were obtained using a whole-head 122-channel magnetometer and analyzed with Fourier statistical analysis. External transcranial magnetic stimulation (TMS) in the order of pico Tesla was applied on the above patients with proper field characteristics (magnetic amplitude : 1-7.5 pT, frequency : the alpha-rhythm of the patient: 8-13 Hz) which were obtained prior to TMS. The MEG recordings after the application of TMS showed a rapid attenuation of the high abnormal activity followed by an increase of the low frequency components toward the patients' alpha-rhythm. The patients responded to the TMS with a feeling of relaxation and partial or complete disappearance of tremor, muscular ache and levodopa induced dyskinesias as well as rapid reversed visuospatial impairment, which were followed by a corresponding improvement and normalization of the MEG.