Region‐specific insular volumetric decreases in drug‐naive, first‐episode schizophrenia and their unaffected siblings

Abstract

Decreased insular volume may be one of the anatomical alterations caused by schizophrenia. The possibility of region-specific insular volumetric reduction as an endophenotype and/or a possible treatment predictor is a critical issue with great implications for the diagnosis and prognosis of the disease. The sample of the current study comprised 44 drug-naive and first-episode patients, 42 unaffected siblings, and 44 healthy controls. A computational anatomy toolbox (CAT12) was applied to analyze the structural images with a fine-grained, cross-validated brainnetome atlas. Correlation analysis and support vector regression (SVR) were used to determine the relationship between insular deficits and symptomatic severity among patients. The gray matter volume (GMV) values in the left hypergranular insula (G) exhibited the following pattern: patients < siblings < controls. GMV values in the right ventral agranular insula (vIa) and baseline Positive and Negative Syndrome Scale negative symptoms subscale scores among patients showed a positive correlation (r = 0.384, p = .010). Further SVR analysis exhibited a significantly positive correlation between GMV values in the right vIa and negative symptomatic improvement among patients (r = 0.537, p < .001). Results suggested the presence of region-specific insular volumetric decreases in first-episode schizophrenia. Thus, volumetric decrease in left G might be a potential endophenotype for schizophrenia, and GMV values in right vIa might be used to predict negative symptomatic improvement in schizophrenia. K E Y W O R D S endophenotype, gray matter volume, insula, schizophrenia, treatment response

Meta-analysis of structural and functional brain abnormalities in schizophrenia with persistent negative symptoms using activation likelihood estimation

“…The insula plays a key role in monitoring internal emotional states ( 62 ) and regulating the influences of emotion on cognitive processes ( 63 , 64 ). Many studies have reported abnormalities in the insula which were related to negative symptoms in schizophrenia ( 17 , 65 ). These are in accordance with findings that a volumetric decrease of the insula relative to controls could be detected in schizophrenia with PNS ( 66 , 67 ).…”

Decreased resting-state neural signal in the left angular gyrus as a potential neuroimaging biomarker of schizophrenia: An amplitude of low-frequency fluctuation and support vector machine analysis

“…Researchers have focused on these regional brain abnormalities when seeking to define biomarkers of SCH ( 17 , 18 ). Li et al, for example, utilized volumetric decreases in the left insula as a potential diagnostic endophenotype for SCH ( 19 ), while others have reported early decreases in global-brain functional connectivity in the bilateral anterior cingulate cortex (ACC) as a promising predictor of SCH patient therapeutic outcomes ( 20 ). In a recent article, Li et al established a novel hypothesis-driven neuroimaging biomarker of SCH through a comparison of these patients and healthy control (HC) individuals, achieving > 80% accuracy ( 17 ).…”

Altered Anterior Insular Metabolic Connectivity in Asymptomatic MAPT P301L Carriers

“…The functions of insula subregions were reported in previous studies: 1) G: perception, somesthesis, and pain; 2) dIa: perception, somesthesis, and pain; action and inhibition; 3) vId/vIg: perception, somesthesis, and pain; olfaction; emotion and disgust, fear; 4) dIg: perception, somesthesis, and pain; emotion and disgust; interoception and sexuality; 5) dId: perception, somesthesis, and pain; perception and gustation; 6) vIa: perception and gustation; action and inhibition [17,18,21]. The anterior insula was the key region of the salient network which was vulnerable in FTD [19].…”

“…In our study, subregions of vIa and dIa constitute the anterior insula. It was known that the vIa and dIa regions were associated with functions of action and inhibition [17,18,21]. Behavior disinhibition was a characteristic manifestation of bvFTD, presented as socially inappropriate behavior, loss of manners, and impulsive, rash, or careless actions [1], which was corresponding with impairment of the function in the Fig.…”