Masked smoking‐related images modulate brain activity in smokers

Abstract

The questions of whether and how indiscriminate drug-related stimuli could influence drug-users are important to our understanding of addictive behavior, but the answers are still inconclusive. In the present preliminary functional magnetic resonance imaging study using a backward masking paradigm, the effect of indiscriminate smoking-related stimuli on 10 smokers and 10 nonsmokers was examined. The BOLD response showed a significant reduction (P = 0.001) in the right amygdala of smokers when they viewed but did not perceive masked smoking-related stimuli, while no significant differences were found in the nonsmoker group. More voxels in anterior cingulate cortex were negatively correlated with the amygdala during the masked smoking-related picture condition in smokers but not in nonsmokers, whereas more positively correlated voxels were observed during the masked neutral condition. The BOLD response in drug-users indicates the amygdala responds to drug-related stimuli that are below the perceptual threshold. The functional connectivity data suggest a functional interaction between the amygdala and the anterior cingulate cortex when drug users view 33 ms back-masked drug-related stimuli. This observation suggests that the amygdala plays an important role in the indiscriminate drug-related cue process.

The relevance and treatment of cue-induced cravings in tobacco dependence

“…A spate of recent studies have also documented specific patterns of brain activation associated with cue exposure and craving, evident in brain imaging studies (Wilson, Sayette, & Fiez, 2004) as well as in electroencephalography analyses (Warren & McDonough, 1999;Zhang et al, 2008). In brain imaging studies, activation in the amygdala, anterior cingulate cortex, and orbitofrontal cortex, and other areas associated with motivation and reward is prominent.…”

Effect of Brain Structure, Brain Function, and Brain Connectivity on Relapse in Alcohol-Dependent Patients

“…A study 30 investigating functional connectivity during a backward masking paradigm with smoking-related stimuli in smokers and nonsmokers observed altered connectivity between the anterior cingulate cortex and the amygdala in smokers but not in nonsmokers. Gu et al 31 reported decreased functional connectivity within the mesocorticolimbic brain reward system in chronic cocaine users (1) between the ventral tegmental area (VTA) and a region encompassing the thalamus/ lentiform nucleus/nucleus accumbens, (2) between the amygdala and the MPFC, and (3) between the hippocampus and the dorsal MPFC.…”

Neuroanatomical Structures Underlying the Extinction of Drug-Seeking Behavior

“…In a previous study, these same investigators showed that local infusions of glucose also facilitated extinction of an amphetamine CPP [192]. Botreau and colleagues enhanced NMDA receptor function, which has been shown to mediate the consolidation of drug-related memories [184,185,193], with local infusions into the BLA of DCS to facilitate the extinction of a cocaine CPP [81]. In this study, control animals maintained a preference for the cocaine-paired chamber until their sixth extinction session whereas DCS treated animals extinguished a cocaine CPP after only three extinction sessions and maintained a neutral preference in extinction tests 3 and 14 days later [81].…”

“…Therefore, activity in the BLA appears to be necessary for drug-related cues and contexts to influence instrumental behavior [180,181] such as cue-induced reinstatement of cocaine-seeking behavior [182,183]. Furthermore, both current and former drug addicts exposed to drug-related cues (e.g., pictures of needles or drugs) show increased activity in the amygdala [184,185].…”