Functional connectivity of reward and cognitive control network in chronic heroin addicts: a resting-state functional MRI study

Abstract

Objective To explore the changes and effect of functional connectivity(FC) of reward network in chronic heroin addicts(HA) using resting-state fMRl(rs-fMRI). Methods rs-fMRI was performed on 26 chronic heroin addicts(HA group) and 25 matched normal volunteers(control group).The rs-fMRI data were proceeded by usingrs-fMRI(DPARSF) software on Matlab 2009a. Bilateral nucleus accumbens(Nacc) were set as ROIs. Then the mean time series of ROI were compared with other voxels within the brain by the rs-fMRI data analysis toolkit(REST) . Intra-and inter-group analysis was performed with single sample and two sample t test respectively. The association of intensity of FC in brain regions and the duration/doses of heroin consumption was investigated. Results In HA group, positiveresting-state FC compared with the ROIs was found in frontal gyms, dorsal striatum, thalamus and pons, while temporal lobe, negative found in part of parietal cortex and occipital cortex, part of dorsal lateral prefrontal cortex and cerebellum. Within control group, positive FC compared with the ROIs was found in frontal gyms, dorsal striatum, thalamus, hippocampal gyrus and pons, occipital cortex, negative FC with ROIs found in part of dorsal lateral prefrontal cortex and cerebellum(P 26). Compared with the control group,the FC between the right Nacc and the bilateral calcarinegyrus, left middle occipital gyrus (voxel numbe r=31, 28, 47; t=3.99, 3.74, 3.74; and P 0.05) . Conclusion The abnormal interaction between Nacc and the regions involved in cognitive control and visual spatial attention may contribute to the heroin addiction. Key words: Heroin dependence; Magnetic resonance imaging