Parietal Cortex Volume and Functions in Major Depression and Bipolar Disorder: A Cloud-Based Magnetic Resonans Imaging Study.

Introduction: The present study aimed to compare the Parietal Lobe (PL) volumes and Cancellation Test (CT) performances of euthymic patients with Bipolar Disorder-1 (BD) and Major Depressive Disorder (MDD), and healthy controls.

Methods: The present study included 63 participants in three groups; two patient groups in remission involving patients with BD and MDD diagnosed according to DSM-5 and a control group with healthy individuals. Sociodemographic Data Form, CT, and Hand Preference Questionnaire were applied to all participants. Participant PL volumes were measured with the Cloud-Based Brain Magnetic Resonance Image Segmentation - Parcellation System.

Results: Both patient groups exhibited lower PL volume when compared to the control group, and there was no difference between the patient groups based on PL volume. It was determined that MDD and BB patients scored less in the CT when compared to the control group. There was a weak correlation between right and left PL volumes and CT performances.

Conclusion: The present study findings demonstrated that BD and MDD patients in remission exhibited lower PL volume and CT performance when compared to healthy controls, emphasizing that PL could be structurally and functionally significant in the pathophysiology of mood disorders.