rTMS stimulation and evaluations
NRS
rTMS simulations were carried out using a Magstim Rapid2 stimulator (Magstim Company, Spring Gardens, UK) with a figure-of-eight coil (double wings of 70-mm diameter). Coil placement was 5 cm anterior to the left and right motor hotspots. The resting motor threshold (RMT) of the right abductor pollicis brevis muscle was used to determine the lowest strength of TMS needed to elicit at least five motor-evoked potentials ≥ 50μV over 10 trials. Patients in the CT group received 15 sessions of bilateral active rTMS (five times a week for 3 weeks). The total pulse was 1600 per session with 90% RMT. First, intermittent theta burst stimulation (iTBS) was applied to the left DLPFC for 800 pulses, then, 800 pulses were applied to the right DLPFC at 1 Hz.ERPs were measured with MEB-9200 electromyogram/evoked potential equipment (Neuropack, Nihon Koden, Japan). The recording electrode was placed at Cz in the 10/20 system and the reference electrode was placed as a parallel electrode at the bilateral mastoid. MMN was evoked via headphones in the auditory oddball paradigm. Standard stimuli (60 dB nHL, 1000 Hz tones, envelope line of rise-plateau-fall were 10–100-10 ms) and deviant stimuli (80 dB nHL, 2000 Hz tones, the same as the envelope line) were presented in a ratio of 80%:20% in a randomized sequence, with a stimulus ratio at 1 Hz. The signals were averaged 40 times. MMN was obtained using subtractive processing between signals induced by deviant and standard stimuli in the absence of active attention. Subjects were not instructed to give any response to the target, only to lie relaxed with their eyes closed. The P300 was recorded under the same odd-ball paradigm, 30 times overlaid, and the waves were digitally filtered with a bandpass of 0.1 − 100 Hz. Subjects were instructed to press a button in response to the target. Analysis time and sensitivity were 100 ms/div and 20 μV/div, respectively, for all data. For all subjects, ERPs were measured and HAMD and NRS scores were evaluated three times: at baseline, after 3 weeks, and after 6 weeks.