Psychiatric University Hospital Zurich, Zurich, Switzerland.
Faculty of Psychology, University of Vienna, Vienna, Austria.
Addict Biol. 2022 Jan;27(1):e13083. doi: 10.1111/adb.13083. Epub 2021 Aug 7.
Tobacco smoking is one of the leading causes of preventable death and disease worldwide. Most smokers want to quit, but relapse rates are high. To improve current smoking cessation treatments, a better understanding of the underlying mechanisms of nicotine dependence and related craving behaviour is needed. Studies on cue-driven cigarette craving have been a particularly useful tool for investigating the neural mechanisms of drug craving. Here, functional neuroimaging studies in humans have identified a core network of craving-related brain responses to smoking cues that comprises of amygdala, anterior cingulate cortex, orbitofrontal cortex, posterior cingulate cortex and ventral striatum. However, most functional Magnetic Resonance Imaging (fMRI) cue-reactivity studies do not adjust their stimuli for emotional valence, a factor assumed to confound craving-related brain responses to smoking cues. Here, we investigated the influence of emotional valence on key addiction brain areas by disentangling craving- and valence-related brain responses with parametric modulators in 32 smokers. For one of the suggested key regions for addiction, the amygdala, we observed significantly stronger brain responses to the valence aspect of the presented images than to the craving aspect. Our results emphasize the need for carefully selecting stimulus material for cue-reactivity paradigms, in particular with respect to emotional valence. Further, they can help designing future research on teasing apart the diverse psychological dimensions that comprise nicotine dependence and, therefore, can lead to a more precise mapping of craving-associated brain areas, an important step towards more tailored smoking cessation treatments.
吸烟是全球可预防死亡和疾病的主要原因之一。大多数吸烟者都想戒烟，但戒烟的复发率很高。为了改进当前的戒烟治疗方法，需要更好地了解尼古丁依赖和相关渴求行为的潜在机制。线索驱动的香烟渴求研究一直是研究药物渴求的神经机制的特别有用的工具。在这里，人类的功能神经影像学研究已经确定了一个与吸烟线索相关的渴求核心脑反应网络，该网络包括杏仁核、前扣带皮层、眶额皮层、后扣带皮层和腹侧纹状体。然而，大多数功能磁共振成像（fMRI）线索反应性研究并没有调整其刺激的情绪效价，而情绪效价被认为是混淆与吸烟线索相关的渴求脑反应的因素。在这里，我们通过在 32 名吸烟者中使用参数调制器来分离渴求相关和效价相关的脑反应，来研究情绪效价对关键成瘾脑区的影响。对于被认为是成瘾关键区域之一的杏仁核，我们观察到与呈现的图像的效价方面相比，对渴求方面的大脑反应明显更强。我们的结果强调了在设计线索反应性范式时需要仔细选择刺激材料，特别是在情绪效价方面。此外，它们可以帮助设计未来关于分离构成尼古丁依赖的各种心理维度的研究，从而可以更精确地映射与渴求相关的脑区，这是朝着更有针对性的戒烟治疗迈出的重要一步。
