Brain activation to cocaine cues and motivation/treatment status

Abstract

Motivation to change is believed to be a key factor in therapeutic success in substance use disorders; however, the neurobiological mechanisms through which motivation to change impacts decreased substance use remain unclear. Existing research is conflicting, with some investigations supporting decreased and others reporting increased frontal activation to drug cues in individuals seeking treatment for substance use disorders. The present study investigated the relationship between motivation to change cocaine use and cue-elicited brain activity in cocaine-dependent individuals using two conceptualizations of 'motivation to change': (1) current treatment status (i.e. currently receiving versus not receiving outpatient treatment for cocaine dependence) and (2) self-reported motivation to change substance use, using the Stages of Change Readiness and Treatment Eagerness Scale. Thirty-eight cocaine-dependent individuals (14 currently in treatment) completed a diagnostic assessment and an fMRI cocaine cue-reactivity task. Whole-brain analyses demonstrated that both treatment-seeking and motivated participants had lower activation to cocaine cues in a wide variety of brain regions in the frontal, occipital, temporal and cingulate cortices relative to non-treatment-seeking and less motivated participants. Future research is needed to explain the mechanism by which treatment and/or motivation impacts neural cue reactivity, as such work could potentially aid in the development of more effective therapeutic techniques for substance-dependent patients.

Keywords: Cocaine dependence; SOCRATES; cue reactivity; fMRI; motivation to change; treatment seeking.

© 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

Figures

Figure 1

SPM map of blood oxygen level dependent (BOLD) response to cocaine cues minus neutral objects across all participants using a voxelwise threshold of z = 3.09 and a corrected cluster threshold of p < 0.05. Cocaine cues were associated with significant activation in left occipital cortex, left superior frontal gyrus, right DLPFC, bilateral hippocampus, right amygdala, posterior cingulate cortex, and left OFC.

Figure 2

SPM map of blood oxygen level dependent (BOLD) response to cocaine cues minus neutral objects in untreated versus treated participants using a voxelwise threshold of z = 2.33 and a corrected cluster threshold of p < 0.05. Untreated participants had higher activation to cocaine cues in the left occipital cortex (uppermost panel), left DLPFC and OFC (upper-middle panel), right DLPFC (lower-middle panel), and posterior cingulate cortex (lowermost panel).

Figure 3

Associations between blood oxygen level dependent (BOLD) response to cocaine cues minus neutral objects and scores on the SOCRATES using a voxelwise threshold of z = 2.33 and a corrected cluster threshold of p < 0.05. Low “recognition” scores were associated with higher activation in temporal and occipital regions, right superior frontal gyrus, right and left frontal poles, and anterior and posterior cingulate cortex (pictured in blue). Low “ambivalence” scores were associated with higher activation in left hippocampus, right intracalcarine cortex, and left middle frontal gyrus (pictured in green). Low “taking steps” scores were associated with higher activation in right DLPFC, right frontal pole, and right paracingulate gyrus (pictured in red).