In order to explore the effect of repetitive TMS, which has shown to be effective in intractable depression, we will examine resting-state, default-mode network functional connectivity in patients with major depression. We will use a double-blind, sham-controlled design. Our target sample size is 60(30 patients will be treated by active rTMS, the other 30 will be treated by sham rTMS). We will apply 10-day course of 10 Hz rTMS on left dorsolateral prefrontal cortex of the subjects.

Up to now, 24 patients with major depression and 6 normal controls are enrolled. Twenty-three patients and 4 normal participants have taken 10 days rTMS. One patients and one control withdrew their consent without any reason and one control withdrew the consent because of headache.

We scanned fMRIs(to examine functional connectivity)twice for each participant, which were taken 3 days before the first and 3 days after the last rTMS.

All of participants have not reported side effects except mild headahe. There's been no seizure event up to now.

Inclusion Criteria:

• DSM-IV major depressive episode
• Failure of at least 3 different kind of antidepressant

Exclusion Criteria:

• Organic brain disorder
• Other diagnosis of DMS-IV except nicotine dependence
• History of seizure disorder