A complementary study by Fitzgerald et al (2007) combined rTMS with fMRI to evaluate the effects of 1Hz rTMS for the treatment of auditory hallucinations on verbal task-induced brain activation. They scanned 3 patients while performing a word generation task, before and after receiving rTMS. Four control subjects were also scanned during task performance (but did not receive rTMS). The authors found that hallucination severity was substantially reduced in all three patients, with increases in task-evoked brain activity noted in various brain areas including the left temporoparietal junction, the left frontal-precentral cortex, and the left inferior frontal gyrus. There was also a significant decrease in task-evoked activity in the right middle occipital gyrus. Intriguingly, before treatment patients showed decreased task-evoked activation compared with controls in a number of cortical regions, including bilateral anterior cingulate, left fronto-temporal regions, left frontal-precentral gyrus, among others. Following rTMS, the areas of reduced activation (in comparison with controls) were significantly smaller, suggesting a normalization of pathologic distributed networks.
