Magnetic motor threshold and response to TMS in major depressive disorder

OBJECTIVE: The aim of this study was to examine motor threshold (MT) during treatment with transcranial magnetic stimulation (TMS). METHOD: The TMS was administered to 46 patients with depression and 13 controls. TMS was performed at 90% power of measured MT. The stimulation frequency was 10 Hz for 6 s, for 20 trains, with 30 s inter-train intervals. The trial included 20 sessions. Patients and controls were assessed on various outcome measures. RESULTS: The MT values were comparable between patients and controls. Neither demographic nor clinical variables were factors in determining MT. MT was not shown to have any predictive value regarding outcome of treatment. CONCLUSION: In this study, MT at baseline or changes in MT during the treatment period were not able to discriminate between patients and controls and were not found to have any predictive value with regard to treatment outcome.