Volumetric Deficit Within the Fronto-Limbic-Striatal Circuit in First-Episode Drug Naïve Patients With Major Depression Disorder

Abstract

Background: Depression is a major psychiatric disorder and the leading cause of disability worldwide. Previous evidence suggested certain pattern of structural alterations were induced by major depression disorder (MDD) with heterogeneity due to patients' clinical characteristics and proposed that early impairment of fronto-limbic-striatal circuit was involved. Yet the hypothesis couldn't be replicated fully. Accordingly, this study aimed to validate this hypothesis in a new set of first-episode, drug naïve MDD patients and further explore the neuroimaging biomarker of illness severity using whole-brain voxel-based morphometry (VBM).Materials and Methods: A total of 93 participants, 30 patients with first-episode medication-naïve MDD, and 63 healthy controls were enrolled in the study. VBM was applied to analyze differences in the gray matter volume (GMV) between these two groups. The correlation between the GMV of the identified brain regions and the severity of clinical symptoms quantified by the Hamilton Depression Scale (HAMD) was further conducted in the post-hoc analysis to confirm the role of GMV structural alteration in clinical symptoms.Results: Our results revealed that the brain gray matter volume of the prefrontal lobe, limbic system, striatum, cerebellum, temporal lobe, and bilateral lingual gyri were significantly decreased in MDD patients compared with healthy controls. Besides, the HAMD scores were negatively correlated with GMV of the right insula and positively correlated with that of the right lingual gyrus.Conclusions: Our findings provide robust evidence that gray matter structural abnormalities within the prefronto-limbic-striatal circuit are implicated in the pathophysiology of MDD at an early stage without confounding influence of medication status. Besides, our data suggest that the cerebellum, lingual gyrus, and fusiform gyrus should also be integrated into the brain alterations in MDD. Future synthesis of individual neuroimaging studies and more advanced statistical analysis comparing subfields of the aforementioned regions are warranted to further shed light on the neurobiology of the disease and assist in the diagnosis of this burdensome disorder.

Reduced Brain Gray Matter Volume in Patients With First-Episode Major Depressive Disorder: A Quantitative Meta-Analysis

“…The identification and attrition of the studies are shown in Figure 1 . Finally, the search identified 2,044 studies, and only 19 studies met the inclusion criteria ( 7 , 12 – 24 , 36 – 40 ), of which three reported two separate experiments ( 7 , 20 , 39 ). Our final sample consisted of 619 first-episode MDD patients (371 females and 248 males; mean age 33.43 ± 4.71 years) and 707 HCs (403 females and 304 males; mean age 32.90 ± 4.79 years).…”

“…The identification and attrition of the studies are shown in Figure 1. Finally, the search identified 2,044 studies, and only 19 studies met the inclusion criteria (7,(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(36)(37)(38)(39)(40), of which three reported two separate experiments (7,20,39…”

Abnormal functional connectivity of the nucleus accumbens subregions mediates the association between anhedonia and major depressive disorder

“…The lingual gyrus is associated with high-level visual processing and visual memory [ 61 ]. There is significantly reduced grey matter volume in the prefrontal lobe, limbic system, striatum, lingual gyrus, and fusiform gyrus in MDD patients [ 62 ]. During emotional facial processing, grey matter structural [ 62 – 64 ] and functional abnormalities [ 65 ] are found in the lingual gyrus and fusiform cortices within MDD patients.…”

Neural activity changes in first-episode, drug-naïve patients with major depressive disorder after transcutaneous auricular vagus nerve stimulation treatment: A resting-state fMRI study

“…In addition, researchers discovered that baseline functional stability in the CAL could predict clinical symptoms improvement in depressed patients ( Li et al, 2021 ). Some neuroimaging investigations have demonstrated abnormal GM volume ( Jung et al, 2014 ; Zhang Y. et al, 2020 ), cortical thickness ( Suh et al, 2019 ; Lee et al, 2021 ) of LG and CAL in MDD patients. An earlier study found a link between visual salience and depression symptoms ( Miller et al, 2015 ).…”