Objective: We examined whether baseline-affective responses to lateral visual-field stimulation could predict clinical responses to left, prefrontal, transcranial, magnetic stimulation (TMS) in patients who are depressed.
Background: Schiffer et al have reported that left and right lateral visual-field stimulation can often evoke different (positive versus negative) psychologic responses in a given patient. Some had improvements while looking to the left and others while looking to the right.
Methods: We asked 37 patients who were severely depressed and resistant to treatment (26 women, 11 men) to report changes in affective state in response to two pairs of goggles, each allowing vision out of either the left or right visual field. We then evaluated whether these responses predicted clinical responses to TMS as measured by the percent decrease in the Hamilton Depression Rating Scale (HDRS.4%) scores between baseline and 4 weeks (2 weeks after a 2-week course of daily TMS).
Results: The 20 patients who felt more improvement with right than left lateral visual-field stimulation with 45-second baseline goggle trials had a 42% (+/- SD 22.2) reduction in HSDR.4%. The 15 patients who felt more improvement looking to the left than to the right had an 11% (+/- SD 28.4) decrease in HSDR.4%. Seventy-five percent of the 20 patients in the first group had a decrease in HSDR.4% more than 20%, and 80% of the 15 in the second group had a decrease in this score of less than 20%. A two-tailed Fisher exact test showed a significant difference between the two groups (p = 0.002).
Conclusion: Baseline affective responses to lateral visual-field stimulation predicted clinical responses to left, frontal TMS in depressed patients.