Background: Treatment-resistant depression (TRD) is a relatively common occurrence in clinical practice, with up to 50% to 60% of patients not achieving adequate response following antidepressant treatment. Repetitive Transcranial Magnetic Stimulation (rTMS) treatment for Major Depressive Disorder MDD involves stimulation of the dorsolateral prefrontal cortex which plays an important role in cognitive function and mood. Specific cognitive symptoms can occur as part of MDD.
Methods: We administered the Hopkins Verbal Learning Test–Revised (HVLT-R), modified, and Trail Making Test (TMT) Part B to a patient receiving rTMS treatments for TRD. Treatment sessions included high-frequency (HF) rTMS of the left DLPFC with verbal memory tasks in combination with low-frequency (LF) rTMS to the right dlPFC.
Results: The patient scored higher on the HVLT-R (32 vs 24) after adding 10 sessions of HF left dlPFC treatment to ongoing LF right dlPFC treatment. She completed TMT part B in a shorter time (121 seconds with 0 errors vs 45 seconds with 0 errors). In addition, she subjectively reported improvement of her memory and cognitive functions with bilateral dlPFC sessions.
Conclusions: Bilateral rTMS of the dlLPFC, including HF left dlPFC specifically, may improve verbal memory and executive function in patients with TRD along with an effect on mood.