A Surface-based Morphometry(SBM)study Of Male Youths With Internet Game Disorder Based On Structural MRI

[Objective]To study the cortical morphological characteristics of male youths with Internet gaming disorder?IGD?by using a surface-based morphological measurement method,and to further explore the relationship between cortical morphological changes and the symptom severity of IGD.[Methods]In this study,42 male youths with IGD and 32 age-and education-matched normal controls were recruited.The whole brain structural images were obtained with a 3.0T MRI.The MRI data of the subjects were processed and analyzed by a surface-based morphometry?SBM?approach for measurement of cortical thickness?CT?,and the symptoms of the subjects were evaluated by Internet addiction test?IAT?.An analysis of covariance was used to compare the cortical thickness data between the two groups,with the diagnosis being a fixed variable and age being a covariate.The multiple comparison corrections were performed using FWE?family-wise-error?correction of the whole brain peak level?P<0.05,two-tailed?.The relationship between cortical thickness and symptom severity in young males with IGD was analyzed by a multiple regression analysis.For exploratory analysis,we relaxed the peak significance threshold to 0.001?two-tailed,uncorrected?and a significant threshold of cluster size>100.[Results]Compared with normal controls,male youths with IGD showed increased CT in brain regions,mainly in the right insula(cluster size=1474,MNI_xyz=[38,-17,1],t=6.02),the left insula(cluster size=531,MNI_xyz=[-40,-10,2],t=5.57)and the right inferior temporal gyrus(cluster size=33,MNI_xyz=[57,-47,-22],t=4.68),and decreased CT in brain regions including the including the banks of the right inferior parietal cortex(cluster size=136,MNI_xyz=[46,-45,12],t=-4.93),the banks of the left inferior parietal cortex(cluster size=14,MNI_xyz=[-48,-35,4],t=-4.55),the right precuneus(cluster size=159,MNI_xyz=[19,-70,-31],t=-4.85)and the right precentral gyrus(cluster size=7,MNI_xyz=[49,-8,32],t=-4.53).In addition,there was a significant positive correlation between the left insular cortex thickness and symptom severity in male youths with IGD(cluster size=285,MNI_xyz=[-38,-1,-6],t=4.19,P<0.05).[Conclusion]The present study showed that:1.There were significant increased CT of brain areas in male youths with IGD mainly located in the bilateral insula and right inferior temporal gyrus;2.There were significant decreased CT of brain areas in male youths with IGD mainly located in the banks of the bilateral inferior parietal cortices and the right precuneus;3.The severity of symptoms of male youths with IGD was related to the morphological characteristics of the left insular cortex.Our study expands the current understanding of the morphological features of the cerebral cortex of IGD,and provides clues to reveal the role of the insula in the pathophysiological mechanisms of IGD.