Article

Is Decreased Prefrontal Cortical Sensitivity to Monetary Reward Associated With Impaired Motivation and Self-Control in Cocaine Addiction?

State University of New York at Stony Brook, Brookhaven National Laboratory, P.O. Box 5000, Upton, NY 11973-5000, USA.
American Journal of Psychiatry (Impact Factor: 12.3). 02/2007; 164(1):43-51. DOI: 10.1176/appi.ajp.164.1.43
Source: PubMed

ABSTRACT

This study attempted to examine the brain's sensitivity to monetary rewards of different magnitudes in cocaine abusers and to study its association with motivation and self-control.
Sixteen cocaine abusers and 13 matched healthy comparison subjects performed a forced-choice task under three monetary value conditions while brain activation was measured with functional magnetic resonance imaging. Objective measures of state motivation were assessed by reaction time and accuracy, and subjective measures were assessed by self-reports of task engagement. Measures of trait motivation and self-control were assessed with the Multidimensional Personality Questionnaire.
The cocaine abusers demonstrated an overall reduced regional brain responsivity to differences between the monetary value conditions. Also, in comparison subjects but not in cocaine abusers, reward-induced improvements in performance were associated with self-reports of task engagement, and money-induced activations in the lateral prefrontal cortex were associated with parallel activations in the orbitofrontal cortex. For cocaine abusers, prefrontal cortex sensitivity to money was instead associated with motivation and self-control.
These findings suggest that in cocaine addiction 1) activation of the corticolimbic reward circuit to gradations of money is altered; 2) the lack of a correlation between objective and subjective measures of state motivation may be indicative of disrupted perception of motivational drive, which could contribute to impairments in self-control; and 3) the lateral prefrontal cortex modulates trait motivation and deficits in self-control, and a possible underlying mechanism may encompass a breakdown in prefrontal-orbitofrontal cortical communication.

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    • "Later studies have replicated the lower activation in frontoparietal regions in response to non-drug-related rewards, which suggests impairments in the attentional ORIGINAL ARTICLE doi:10.1111/adb.12329 © 2015 Society for the Study of Addiction Addiction Biology bs_bs_banner processing of emotional stimuli by cocaine users (Goldstein et al. 2007; Asensio et al. 2010). Therefore, it is interesting to continue studying the neural bases of motivated approach behavior in cocaine addiction by analyzing brain reactivity to natural non-drug-related rewards using different conditions and methodological approaches. "
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    ABSTRACT: Cocaine addiction is characterized by alterations in motivational and cognitive processes. Recent studies have shown that some alterations present in cocaine users may be related to the activity of large functional networks. The aim of this study was to investigate how these functional networks are modulated by non-drug rewarding stimuli in cocaine-dependent individuals. Twenty abstinent cocaine-dependent and 21 healthy matched male controls viewed erotic and neutral pictures while undergoing a functional magnetic resonance imaging scan. Group independent component analysis was then performed in order to investigate how functional networks were modulated by reward in cocaine addicts. The results showed that cocaine addicts, compared with healthy controls, displayed diminished modulation of the left frontoparietal network in response to erotic pictures, specifically when they were unpredicted. Additionally, a positive correlation between the length of cocaine abstinence and the modulation of the left frontoparietal network by unpredicted erotic images was found. In agreement with current addiction models, our results suggest that cocaine addiction contributes to reduce sensitivity to rewarding stimuli and that abstinence may mitigate this effect.
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    • "Dysfunctional reward processing, which commonly manifests as the overvaluation of drug-related rewards and undervaluation of other non-drug reinforcers (e.g., food, sex, money), plays a key role in substance abuse (Blum et al., 2000; Garavan et al., 2000; Goldstein et al., 2007; Kalivas and Goldstein, 2005; Versace et al., 2012). This is true for nicotine-dependent individuals, who demonstrate reduced reward reactivity to non-drug reinforcers during nicotine withdrawal (Al-Adawi and Powell, 1997; Powell et al., 2002a,b, 2004). "
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    • "In a recent imaging study, we found that a sub-set of high fat dietary obese rats, those that maintained weight loss at higher level following RYGB, showed an increased activation of brain reward areas in response to cues associated with highly stimulating treats (Thanos et al., 2015). These, and other data, collectively suggest a greater risk for some patients to engage in alternative excessive behavior (Goldstein et al., 2007; Kalivas and Volkow, 2005; Volkow and Baler, 2013; Wang et al., 2004a), and they fit well the clinical observations of increased risk among RYGB patients for substituting food with alcohol (Ertelt et al., 2008; Hsu et al., 1998; King et al., 2012; Suzuki et al., 2012) or use of other substances (Conason et al., 2013; Dutta et al., 2006). The 'symptom "
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