Diffusion tensor imaging (DTI),a noninvasive MRI technique for measuring the integrity and direction of white matter in the brain,is a promising method to explore the pathogenesis of obsessive compulsive disorder (OCD).At present,the etiological research of OCD suggests that,in addition to the classical cortical-striatum-thalamus-cortical (CSTC) circuit,the parietal lobe,temporal lobe,occipital lobe and other regions of the brain are also involved in the pathogenesis of OCD.White matter fibers are important structure of material information communication in various brain regions and affected by individual neurodevelopment.Therefore,it is very important to explore the characteristics of white matter fiber in the brain of patients with OCD by using diffusion tensor imaging technology clarifying its role in the occurrence of OCD.This paper reviews the studies on uncinate fasciculus,superior longitudinal fasciculus,corpus callosum in adult DTI studies and the progress of DTI studies on children and adolescents.

Objective:To explore the effect of childhood traumatic experience and impulsive traits on symptom dimensions in patients with obsessive-compulsive disorder(OCD).Methods:A cross-sectional study was performed to enroll 134 patients with obsessive-compulsive disorder diagnosed by DSM-Ⅳ and 82 healthy controls to match. The obsessive compulsive inventory-revised(OCI-R) questionnaire, and the Barratt impulsiveness scale (BIS-11) and Childhood trauma questionnaire-short form(CTQ-SF) were used to assess the symptom dimensions, impulsive traits, and childhood trauma levels of two groups.The Yale-Brown Obsessive-compulsive Scale (Y-BOCS) was used to assess severity of disease in OCD patients. The scores of each dimension of obsessive-compulsive symptoms were used as dependent variables. The impulse characteristics of different components and childhood trauma scores were independent variables. Multivariate regression analysis was used to explore the influence of impulsive traits and childhood trauma on obsessive-compulsive symptoms.Results:The scores of OCD patients in nonplanning impulsivity (26.80±4.57), attentional impulsivity(18.96±3.51), emotional abuse(6 (5, 9)), physical abuse (5(5, 6)), emotional neglect (11 (9, 14)) were higher than those in healthy controls ((24.39±4.15), (16.18±2.76), 6 (5, 7), 5 (5, 5), (10.00±3.42) respectively) ( P<0.05, P<0.01). Each subscore of OCI-R in patients with OCD was significantly higher than those in healthy controls (all P<0.01). Multiple regression analysis indicated that the ordering scores of obsessive-compulsive patients was affected by attentional impulsivity and physical neglect ( B=0.191, P=0.011; B=0.273, P=0.005). The emotional abuse was the major impact factor of the hoarding symptom ( B=0.204, P=0.002). The score of obsessions was affected by attentional impulsivity and emotional abuse ( B=0.499, P<0.01; B=0.175, P=0.008). The scores of neutralizing were influenced by attentional impulsivity and physical neglect ( B=0.365, P<0.01; B=0.199, P=0.034). Conclusion:Childhood trauma and attentional impulsivity of OCD patients have different effects on different obsessive-compulsive symptoms.