OBJECTIVETo investigate the changes in orbitofrontal cortex (OFC) functional connectivity and its association with decision-making deficits in chronic heroin-dependent individuals (HDIs) and explore the neural mechanisms of heroin addiction and relapse.

METHODSFourteen male chronic HDIs and 14 healthy subjects matched for age, education, and nicotine consumption participated in this study. Resting state functional magnetic resonance imaging (fMRI) was performed using a 1.5 T MR scanner. Functional connectivity of the OFC and the rest of the brain were calculated using REST software. Voxel-based analysis of the functional connectivity maps between the control and HDI groups was performed with two-sample t test. The Iowa gambling task (IGT) was used to assess the participants' decision making during uncertainty.

RESULTSCompared with the control group, the HDIs showed significantly decreased functional connectivity of the OFC and the right inferior parietal lobule (rIPL) (t=3.5, P<0.05). A significant negative correlation was noted between the functional connectivity of the OFC-rIPL and performance level at the IGT.

CONCLUSIONThe OFC-rIPL functional connectivity is significantly disrupted in HDIs, which may be the neural basis for decision-making deficits.