Money addiction as a potential diagnostic category among behavioral addictions: Imbalanced brain valuation and control networks as a candidate etiology
Creators: name: Haracz, John
Publisher: name: F1000Research
Year: 2016

description: DSM-5 expanded the DSM-IV-TR chapter on substance-related disorders to include gambling disorder in a new chapter titled “Substance-Related and Addictive Disorders”. Gambling disorder thereby became the first behavioral addiction to be formally ratified as a clinical entity (Clark, 2014; Robbins and Clark, 2015). The new DSM-5 (p. 481) chapter states “All drugs that are taken in excess have in common direct activation of the brain reward system… .” Neuroeconomic studies using functional magnetic resonance imaging (fMRI) have shown activations of nucleus accumbens (NA), a brain reward center, when subjects are exposed to monetary rewards (Haber and Knutson, 2010). Therefore, a systematic literature review will be conducted to assess whether future psychiatric nosologies should include money addiction as a diagnostic category involving an excessive behavioral focus on money accumulation, even in the absence of typical gambling activities.<br><br>In addition to a review of the above neuroeconomic studies, a literature review of reward-system function will be conducted in relation to excessive behavioral patterns that have been proposed as potential behavioral addictions (e.g., internet gaming, sex addiction, exercise addiction, and obesity or eating disorders; DSM-5; Clark, 2014; Robbins and Clark, 2015).<br><br>Results from neuroimaging and genetic studies suggest reward-system alterations in potential behavioral addictions (Clark, 2014; Robbins and Clark, 2015). Imbalanced activity in neural circuits may be etiologically involved in substance-related and behavioral addictions. For example, fMRI studies of functional connectivity revealed that, compared to control subjects, individuals with heroin addiction (Xie et al., 2014; Zhai et al., 2015; Zou et al., 2015) or internet gaming disorder (Dong et al., 2015) show greater connectivity between regions in the reward valuation circuit (e.g., NA, ventromedial prefrontal cortex, and amygdala), but less connectivity in the frontoparietal cognitive-control circuit. This imbalanced neurocircuitry may underlie the impulsivity associated with substance abuse and pathological gambling (Bickel et al., 2012). Accordingly, a preference for immediate rewards by healthy subjects was associated with increased connectivity in the valuation circuit (Li et al., 2013; van den Bos et al., 2014), whereas larger delayed rewards were preferred by subjects with enhanced frontoparietal connectivity (Li et al., 2013).<br><br>The above evidence may represent initial steps toward developing Research Domain Criteria (Casey et al., 2013; Cuthbert and Insel, 2013; Insel et al., 2013), which could add dimensional neurobehavioral measures to categorical diagnoses in future psychiatric nosologies. To assist with determining whether these nosologies should include money addiction, these types of neuroimaging studies could be conducted with subjects who compulsively seek money in a maladaptive manner that disrupts their social or occupational functioning.