Altered interhemispheric resting-state functional connectivity in young male smokers

With the help of advanced neuroimaging approaches, previous studies revealed structural and functional brain changes in smokers compared with healthy non-smokers. Homotopic resting- state functionalconnectivity between the corresponding regions in cerebral hemispheresmay help us to deduce the changes of functional coordination in the whole brain of young male smokers. Functional homotopy reflects an essential aspect of brain function and communication between the left and right cerebral hemispheres, which is important for the integrity of brain function. However, few studies used voxel mirrored homotopic connectivity (VMHC) method to investigate the changes of homotopic connectivity in young male smokers. Twenty-seven young male smokers and 27 matched healthy male non-smokers were recruited in our study. Compared with healthy male non-smokers, young male smokers showed decreased VMHC values in the insulaand putamen, and increased VMHC values in the prefrontal cortex. Correlation analysis demonstrated that there were significant positive correlations between the average VMHC values of the prefrontal cortexand pack-yearsin young male smokers. In addition, significant negative correlation was found between the average VMHC values in the insulaand pack-years. Our results revealed the disrupted homotopic resting- state functionalconnectivity in young male smokers. The novel findings may extend our understanding of smoking.