Neural Correlates of Social Influence Among Cannabis Users

Abstract

Purpose of review Although peer influence is an important factor in the initiation and maintenance of cannabis use, few studies have investigated the neural correlates of peer influence among cannabis users. The current review summarizes research on the neuroscience of social influence in cannabis users, with the goal of highlighting gaps in the literature and the need for future research. Recent findings Brain regions underlying peer influence may function differently in cannabis users. Compared to non-using controls, regions of the brain underlying reward, such as the striatum, show greater connectivity with frontal regions, and also show hyperactivity when participants are presented with peer information. Other subcortical regions, such as the insula, show hypoactivation during social exclusion in cannabis users, indicating that neural responses to peer interactions may be altered in cannabis users. Summary Although neuroscience is increasingly being used to study social behavior, few studies have specifically focused on cannabis use, and therefore it is difficult to draw conclusions about social mechanisms that may differentiate cannabis users and controls. This area of research may be a promising avenue in which to explore a critical factor underlying cannabis use and addiction.

Shifted balance of dorsal versus ventral striatal communication with frontal reward and regulatory regions in cannabis‐dependent males

“…Moreover, employing a fully data-driven network approach that combines the ICC with a pattern classification demonstrated that the general connectivity patterns of the VS and DS can reliably discriminate between cannabis-dependent individuals and controls. As such, the present data are in line with previous studies reporting altered VS and DS activity in chronic cannabis users during drug cue reactivity, reward processing (Weinstein et al, 2016;Wrege et al, 2014;Yanes et al, 2018) and social decision making (Gilman, 2017).…”

“…Red color indicated stronger functional connectivity with VS than DS and blue color indicated stronger functional connectivity with DS than VS. All images were thresholded at p < .05, TFCE corrected (Weinstein et al, 2016;Wrege et al, 2014;Yanes et al, 2018) and social decision making (Gilman, 2017). In line with animal and human data that emphasize the specific contributions of the VS and DS, subregion-specific differences between cannabis users and controls mapped to the nucleus accumbens and the caudate nucleus.…”

“…Despite the important contributions of these studies to characterize mechanisms of cannabis dependence, the task-based approach does not allow direct evaluation of the ventral to dorsal striatal shift due to: (a) limitation of task-based fMRI to regions engaged by the experimental paradigm (Weinstein et al, 2016) and (b) stimulus and context dependences of striatal alterations in cannabis dependence (Gilman, 2017;. Resting state fMRI functional connectivity (rsfMRI-FC) approaches allow a more holistic assessment of functional alterations in the absence of task or contextual modulation.…”

Shifted balance of dorsal versus ventral striatal communication with frontal reward and regulatory regions in cannabis dependence

“…Moreover, employing a fully-data driven network approach that combines the intrinsic connectivity contrast with a pattern classification demonstrated that the general connectivity patterns of the VS and DS can reliably discriminate between cannabis-dependent individuals and controls. As such, the present data are in line with previous studies reporting altered ventral and dorsal striatal activity in chronic cannabis users during drug cue reactivity, reward processing (Weinstein et al, 2016;Wrege et al, 2014;Yanes et al, 2018) and social decision making (Gilman, 2017). Further, our data emphasize the important contribution of striatal maladaptations in addiction which might reflect a common pathological pathway across addictive disorders.…”

“…Despite the important contributions of these studies to characterize mechanisms of cannabis dependence, the task-based approach does not allow direct evaluation of the ventral to dorsal striatal shift due to (1) limitation of task-based fMRI to regions engaged by the experimental paradigm (Weinstein et al, 2016), and (2) stimulus-and context-dependence of striatal alterations in cannabis dependence (Gilman, 2017;Zimmermann et al, 2017b). Resting state fMRI functional connectivity (rsfMRI-FC) approaches allow a more holistic assessment of functional alterations in the absence of task or contextual modulation.…”