a Centre de Recherche de l'Institut , Universitaire en Santé Mentale de Montréal , Montréal , Canada.
b Department of Psychiatry , University of Montreal , Montreal , Canada.
J Dual Diagn. 2019 Jan-Mar;15(1):8-15. doi: 10.1080/15504263.2018.1526432. Epub 2018 Nov 16.
Compared to the general population, tobacco smoking cessation rates are lower in populations with schizophrenia. Unfortunately, the potential neurophysiologic mechanisms underlying these low cessation rates in schizophrenia have been seldom studied using functional neuroimaging. Recently, it has been shown that tobacco cravings are increased in smokers with schizophrenia compared to smokers with no comorbid psychiatric disorder. Given the critical role of the brain reward system in the neurobiology of addiction, we sought to examine the functional connectivity of core regions of this system in smokers with schizophrenia during the viewing of appetitive smoking cues. Smokers with ( = 18) and without ( = 24) schizophrenia were scanned using functional magnetic resonance imaging while viewing appetitive cigarette images. Functional connectivity analyses were performed using the bilateral nucleus accumbens as the seed regions. Smokers with schizophrenia and smokers with no psychiatric comorbidity did not differ in subjective cravings in response to appetitive smoking cues. However, in smokers with schizophrenia relative to control smokers, we found an increased connectivity between the nucleus accumbens and regions involved in the default mode network (e.g., middle temporal gyrus and precuneus), which are involved in self-referential processes. Moreover, a positive correlation was observed between the left nucleus accumbens and left middle temporal gyrus connectivity and cigarette cravings across both groups of smokers. These results highlight a key role of the nucleus accumbens in cigarette craving in schizophrenia and suggest that the subjective valuation of cigarette cues is increased in this population. Similar neurofunctional studies on cravings for other psychoactive substances in schizophrenia are warranted.
与一般人群相比，精神分裂症患者的戒烟率较低。不幸的是，使用功能神经影像学研究这些精神分裂症患者低戒烟率的潜在神经生理机制的研究很少。最近，研究表明，与没有合并精神障碍的吸烟者相比，精神分裂症吸烟者的烟草渴求增加。鉴于大脑奖励系统在成瘾的神经生物学中的关键作用，我们试图在观看有吸引力的吸烟线索时，检查精神分裂症吸烟者中该系统核心区域的功能连接。 使用功能磁共振成像对 18 名患有精神分裂症的吸烟者（ = ）和 24 名没有精神分裂症的吸烟者（ = ）进行扫描，同时观看有吸引力的香烟图像。使用双侧伏隔核作为种子区域进行功能连接分析。 有精神分裂症和没有精神共病的吸烟者在对有吸引力的吸烟线索的主观渴望方面没有差异。然而，与对照组吸烟者相比，我们发现精神分裂症吸烟者的伏隔核与默认模式网络中涉及自我参照过程的区域（例如，颞中回和楔前叶）之间的连接增加。此外，在两组吸烟者中，左侧伏隔核与左侧颞中回连接与吸烟渴望之间存在正相关。 这些结果强调了伏隔核在精神分裂症吸烟渴望中的关键作用，并表明该人群对香烟线索的主观评估增加。有必要对精神分裂症中其他精神活性物质的渴望进行类似的神经功能研究。
