Roya Mohammadi Kashkooli - Department of Psychology, Faculty of Education and Psychology, University of Isfahan, Isfahan, Iran
Mahgol Tavakoli - Department of Psychology, Faculty of Education and Psychology University of Isfahan, Isfahan, Iran
Sahar Borazjani - Department of Psychology, Faculty of Education and Psychology, University of Isfahan, Isfahan, Iran

Background and Aim: Major depressive disorder (MDD) and generalized anxiety disorder (GAD) are both common disorders, nevertheless, when they co-occur, they can make treatment challenging. Compared to patients who do not suffer from comorbidity, patients with comorbid depression and anxiety have more severe disorder, chronicity, and significant impairment in work and social functioning. Treatment options for these disorders generally include drug therapy or psychotherapy. However, a significant percentage of patients do not respond adequately to these treatments, and some patients report disturbing side effects. On the other hand, previous studies acknowledge that changes in brain oscillations (such as theta (θ) oscillations) in specific brain areas can be related to mental disorders such as GAD and MDD. Therefore, in this study, we hypothesized that by modulating theta oscillations using a novel protocol of the TACS method, symptoms related to depression and anxiety can be reduced in MDD with Comorbid GAD. Method: The case of this study was a ۲۶-year-old female who was resistant to treatment and diagnosed with comorbid MDD and GAD. The subject was evaluated with Hamilton Anxiety Rating Scale (HAM-A) and Hamilton Depression Rating Scale (HAM-D) once before the intervention and once after the intervention sessions (after the eighth session of θ-TACS) to evaluate anxiety and depression symptoms. Results: The comparison of the evaluation scores obtained from HAM-A and HAM-D before and after the therapeutic intervention and also at the one-month follow-up showed a significant improvement in the reduction of anxiety and depression symptoms. Conclusion: According to the results of this report, we can hope for the effect of interventions that help to modulate the theta oscillation in those suffering from MDD with Comorbid GAD (such as the method used in this study). Therefore, it is recommended to conduct double-blind randomized controlled trials to determine the effectiveness and further generalization of this intervention.

Transcranial Alternating Current Stimulation, Generalized Anxiety Disorder, Major Depressive Disorder, Comorbidity, Theta Oscillations