Clinical Research Directory

The active iTBS sessions will be delivered using the Magstim Rapid2 stimulator. The iTBS protocol consists of 3-pulse 50-Hz bursts given every 200 ms (at 5 Hz) for 2 s at 8-s intervals for 60 cycles. A 2-s train of iTBS will be repeated every 10 s for a total of 1800 pulses per session. The intensity of stimulation will be set at 80% resting motor threshold (RMT). The target will be the left DLPFC with the coil centered at the MNI coordinate \[-38, 44, 26\] calculated from T1-weighted MRI. The active HD-tDCS will be applied by NeuroConn DC Stimulator Plus. The central anode will be placed over the International 10-20 electrode position F3 and the return peripheral electrodes placed at Fp1, Fz, C3 and F7. Stimulation session will be applied at an intensity of 2 mA, 8-sec fade in and 5-sec fade out, for 20 min. During each session, the subject has to perform a computerized working memory task (i.e., 2-back task). The two times daily sessions will be separated by at least 2 hours.

The active iTBS sessions will be delivered using the Magstim Rapid2 stimulator. The iTBS protocol consists of 3-pulse 50-Hz bursts given every 200 ms (at 5 Hz) for 2 s at 8-s intervals for 60 cycles. A 2-s train of iTBS will be repeated every 10 s for a total of 1800 pulses per session. The intensity of stimulation will be set at 80% resting motor threshold (RMT). The target is the left DLPFC with the coil centered at the MNI coordinate \[-38, 44, 26\] calculated from T1-weighted MRI. In the sham HD-tDCS stimulation, short continuous currents without neuromodulatory effects will be applied to mimic real-stimulation sensations. Specifically, sham stimulation will deliver 40-sec, 2 mA normal-like stimulation, followed by a tiny current pulse (110 μA over 15 ms) for impedance control taking place every 550 ms for the remaining time. The other procedure is the same as the active HD-tDCS stimulation.

In the sham iTBS condition, the patients receive the same iTBS regimen and exact positioning of the coil but stimulations will be delivered using a commercial identical looking figure 8 sham coil (Magstim D70 Air film sham coil) that can produce a similar sound and sensation. In the active HD-tDCS condition, stimulation will be applied by a battery-operated device (NeuroConn DC Stimulator Plus) via 5 carbon rubber electrodes (1 cm radius, high-definition 4 × 1 rings configuration). To target the left DLPFC, the central electrode (anode) will be placed over International 10-20 electrode position F3, with return peripheral electrodes at Fp1, Fz, C3 and F7. Stimulation will be applied at an intensity of 2 milliamp (mA), 8-sec fade in and 5-sec fade out, for 20 min. During each session, the subject has to perform a computerized working memory task (i.e., 2-back task). The two times daily sessions will be separated by at least 2 hours.

In the sham iTBS condition, patients receive the same iTBS regimen and exact positioning of the coil but stimulations will be delivered using a commercial identical looking figure 8 sham coil (Magstim D70 Air film sham coil) that can produce a similar sound and sensation. In the sham HD-tDCS condition, short continuous currents without neuromodulatory effects will be applied to mimic real-stimulation sensations. Specifically, sham stimulation will deliver 40-sec, 2 mA normal-like stimulation, followed by a tiny current pulse (110 μA over 15 ms) for impedance control taking place every 550 ms for the remaining time. The other procedure is the same as the active HD-tDCS stimulation.