Common and Distinct Drug Cue Reactivity Patterns Associated with Cocaine and Heroin: An fMRI Meta-Analysis.

Substance use and substance use disorders (SUDs) represent ongoing major public health crises. Specifically, the use of illicit substances such as cocaine and heroin are responsible for over 50,000 drug related deaths annually. Our study used a comparative meta-analysis procedure to contrast activation patterns that may help explain the behavioral differences observed. PubMed and Google Scholar were searched for studies with within-subject whole brain analyses comparing drug to neutral cues for users of cocaine and heroin. A total of 18 studies were included, 9 in each subgroup. Voxel-based meta-analyses were performed using seed-based d mapping with permuted subject images (SDM-PSI) for subgroup mean analyses and a contrast meta-regression comparing the two substances. Mean analysis results indicated that users of heroin showed more widespread activation in the nucleus accumbens, right inferior and left middle temporal gyrus, the right thalamus, and the right cerebellum while cocaine use was associated with recruitment of lateral prefrontal cortex. Direct comparison of cue reactivity studies in heroin relative to cocaine users revealed greater activation in dopaminergic targets for users of heroin compared to users of cocaine. Differential activation patterns between substances may underlie behavioral differences observed across users of illicit substances, including seeking mood numbing effects in users of heroin. More consistent research methodology is needed to provide adequate studies for stringent meta-analyses examining common and distinct neural activation patterns across substances.