To comparatively study the effects of left or right dorsolateral prefrontal cortex repetitive transcranial magnetic stimulation (rTMS) on time perception in depression.

Patients with mild and moderate depression were randomly divided into left group and right group.Patients in left group received 10 Hz left(n=30) and patients in right group received 1 Hz right(n=32) dorsolateral prefrontal cortex rTMS for 4 weeks. Hamilton depression scale(HAMD) and errors of 600 ms and 3 s time reproduction task used as a index of time perception were assessed before and after rTMS treatment.

The scores of HAMD(before treatment: (20.5±1.7), (20.7±1.6); after treatment: (11.8±2.7), (12.2±2.8) were decreased in both two groups(both P<0.01). In left group, the errors of 3 s time reproduction task(before treatment: (1 059±271)ms; after treatment: (1 023±245)ms) decreased(P<0.01) and errors of 600 ms time reproduction was not significantly changed(P>0.05) after rTMS treatment. In right group, both the errors of 600 ms (before treatment: (550±112)ms; after treatment: (528±110)ms) and 3 s time reproduction task (before treatment: (1 003±247)ms; after treatment: (935±259)ms) were decreased(both P<0.01). Compared with left group patients(-5.1±25.0)ms, (-35.9±69.4)ms, the right group patients had significant lowing of the errors of 600 ms and 3 s time reproduction task((-21.1±31.2)ms, (-68.0±48.0)ms) after treatment(both P<0.01)and had a similar lowing of HAMD(P>0.05). The lowing of the errors of 3 s time reproduction task after treatment was correlated with the lowing of HAMD in left(r=0.365, P=0.043) or right group(r=0.401, P=0.039). The lowing of the errors of 600 ms time reproduction task after treatment was not correlated with the lowing of HAMD in left or right group(both P>0.05).

Either left or right dorsolateral prefrontal cortex rTMS improves the time perception in major depressed patients, especially the latter.

Depression; Transcranial magnetic stimulation; Time perception