%0 Journal Article
%T Distinct homotopic functional connectivity patterns of the amygdalar sub-regions as biomarkers in major depressive disorder.
%A Harel M
%A Amiaz R
%A Raizman R
%A Leibovici A
%A Golan Y
%A Mesika D
%A Bodini R
%A Tsarfaty G
%A Weiser M
%A Livny A
%J J Affect Disord
%V 365
%N 0
%D 2024 Nov 15
%M 39134155
%F 6.533
%R 10.1016/j.jad.2024.08.023
%X BACKGROUND: Major depressive disorder (MDD) affects multiple functional neural networks. Neuroimaging studies using resting-state functional connectivity (FC) have focused on the amygdala but did not assess changes in connectivity between the left and right amygdala. The current study aimed to examine the inter-hemispheric functional connectivity (homotopic FC, HoFC) between different amygdalar sub-regions in patients with MDD compared to healthy controls, and to examine whether amygdalar sub-regions' HoFC also predicts response to Serotonin Selective Reuptake Inhibitors (SSRIs).
METHODS: Sixty-seven patients with MDD and 64 matched healthy controls were recruited. An MRI scan focusing on resting state fMRI and clinical and cognitive evaluations were performed. An atlas seed-based approach was used to identify the lateral and medial sub-regions of the amygdala. HoFC of these sub-regions was compared between groups and correlated with severity of depression, and emotional processing performance. Baseline HoFC levels were used to predict response to SSRIs after 2 months of treatment.
RESULTS: Patients with MDD demonstrated decreased inter-hemispheric FC in the medial (F3,120 = 4.11, p = 0.008, η2 = 0.096) but not in the lateral (F3,119 = 0.29, p = 0.82, η2 = 0.008) amygdala compared with healthy controls. The inter-hemispheric FC of the medial sub-region correlated with symptoms severity (r = -0.33, p < 0.001) and emotional processing performance (r = 0.38, p < 0.001). Moreover, it predicted treatment response to SSRIs 65.4 % of the cases.
CONCLUSIONS: The current study did not address FC changes in MDD biotypes. In addition, structural connectivity was not examined.
CONCLUSIONS: Using a unique perspective of the amygdalar distinct areas elucidated differential inter-hemispheric FC patterns in MDD patients, emphasizing the role of interhemispheric communication in depression.