大麻使用障害における大麻キュー反応性の神経回路網：機能的神経画像研究
Valentina Lorenzetti1, Hannah Sehl1, Arush Honnedevasthana Arun1
1Neuroscience of Addiction and Mental Health Program, Healthy Brain and Mind Research Centre, School of Behavioural and Health Sciences, Faculty of Health Sciences, Australian Catholic University, Fitzroy, Victoria, Australia.
Background:
A common feature of cannabis use disorder (CUD) is an intense reactivity to cannabis cues, which are becoming increasingly visible due to the growth in its decriminalization, accessibility, and marketing of cannabis products. The brain's automatic reactivity to cannabis cues can trigger craving and subsequent use. In this study, we aimed to test neural activity during cannabis cue reactivity in non-treatment-seeking individuals with moderate-to-severe CUD and past attempts to cut down/quit.
Methods:
The study examined 65 individuals with moderate-to-severe CUD and 43 control participants, with a functional magnetic resonance imaging cannabis cue-reactivity task and assessment of mental health and substance use as well as cognitive testing. Group differences in neural responses to cannabis cue reactivity were examined, adjusting for age and sex; correlations with cannabis use characteristics and mental health variables were assessed, accounting for recent substance use.
Results:
Compared with control participants, individuals with CUD showed greater brain activity during cannabis cue reactivity in the superior/middle occipital, medial/lateral orbitofrontal cortex, anterior/posterior cingulate, cerebellar, hippocampus, and middle temporal and lateral parietal cortices (p < .05; cluster k > 10, familywise error corrected). Greater occipital/cerebellar activity correlated with greater subjective arousal toward cannabis images and cannabis withdrawal scores, while anterior cingulate/inferior parietal activity negatively correlated with urinary level of 11-Nor-9-carboxy-Δ9-tetrahydrocannabinol:creatinine (ps < .05).
Conclusions:
Exposure to cannabis cues can elicit greater activity within salience evaluation/attention, motivation, and disinhibition pathways of addiction neurocircuitry in people with moderate-to-severe CUD, consistent with prominent neuroscientific theories of addiction and findings with other substances. Interventions that can suppress brain activity in salience and attention circuits during cannabis cue reactivity may help reduce craving and subsequent use.
