摘要目的:探讨基于全脑静息态功能磁共振成像（rs‐fMRI）的男性吸烟成瘾者内在神经时间尺度（INT）的异常改变。方法:病例对照研究。回顾性分析2019年1月至2021年12月通过网络平台招募的139名男性受试者相关临床资料及全脑rs‐fMRI数据。受试者年龄（34.1±8.8）岁。根据是否存在吸烟成瘾分为吸烟成瘾组（ n=83）和健康对照者（ n=56）。通过计算INT来反映受试者大脑神经活动动力学改变。首先采用单样本 t检验分别获得吸烟成瘾组及健康对照组全脑INT的空间分布图谱。然后采用双样本 t检验将年龄、受教育年限作为协变量，分析吸烟成瘾组与健康对照组INT的差异。最后采用Spearman相关分析探究显著差异脑区INT值与尼古丁依赖量表评分及吸烟指数的关系。 结果:吸烟成瘾组与健康对照组表现出相似的分层神经时间尺度模式，即在感觉运动区INT较短，在顶叶、后扣带回皮层的INT较长。此外，吸烟成瘾组在视觉皮层左侧枕中回（ t峰值=-3.18）、左侧枕上回（ t峰值=-3.66）、双侧距状裂周围皮层（左： t峰值=-3.02，右： t峰值=-3.22）、双侧舌回（左： t峰值=-3.10，右： t峰值=-3.04）、左侧楔叶（ t峰值=-2.97）、默认网络相关脑区［（左侧楔前叶： t峰值=-3.23）、左侧角回（ t峰值=-3.07）、左侧后扣带回皮层（ t峰值=-3.54）］的INT较健康对照组显著减低（高斯随机场校正，体素水平均 P<0.005，团块水平均 P<0.05）。但未发现显著差异脑区INT值与尼古丁依赖量表评分及吸烟指数存在相关性（Bonferroni校正后均 P>0.05）。 结论:与健康对照者相比，吸烟成瘾者在视觉皮层及默认网络神经活动动力学方面存在异常改变。

abstractsObjective:To investigate the abnormal changes of intrinsic neural time scale (INT) in male smoking addicts based on whole brain resting state functional magnetic resonance imaging (rs-fMRI).Methods:A case-control study. The clinical data and whole brain rs-fMRI data of 139 male subjects, aged (34.1±8.8) years, recruited through the online platform from January 2019 to December 2021 were retrospectively analyzed. According to the existence of smoking addiction, they were divided into smoking addiction group ( n=83) and healthy control group ( n=56).INT was calculated to reflect the brain neural activity dynamics. Single sample t test was used to obtain the whole brain spatial distribution maps of INT in smoking addiction group and the control group. Then two-sample t test was conducted to explore the difference of INT between the smoking addition group and the healthy control group, with age and years of education as covariates. Finally, Spearman correlation analysis was used to explore the relationship between INT and nicotine dependence scale score and smoking index. Results:Subjects with smoking addiction and healthy control group showed a similar pattern of hierarchical neural timescales, namely shorter INT in sensorimotor areas and longer INT in parietal lobe, posterior cingulate cortex. In addition, in the smoking addiction group, the left medial occipital gyrus (peak t=-3.18), left suproccipital gyrus (peak t=-3.66), bilateral pericalar cleft cortex (left: peak t=-3.02, right: peak t=-3.22), bilateral lingual gyrus (left: peak t=-3.10, right: t peak=-3.04), left cuneus (peak t=-2.97), default network associated brain region [left anterior cuneus(peak t=-3.23), left angular gyrus (peak t=-3.07), and left posterior cingulate cortex (peak t=-3.54) were significantly lower than those of healthy controls (gaussian random field correction, voxel level all P<0.005, mass level all P<0.05). However, there was no significant correlation between INT and nicotine dependence scale score and smoking index (both P>0.05 after Bonferroni correction). Conclusion:Compared with healthy controls, smoking addicts showed abnormal changes in the dynamics of neural activity in the visual cortex and the default network.