Department of Radiology, University of Colorado School of Medicine, United States; Department of Bioengineering, University of Colorado School of Medicine, United States.
Department of Radiology, University of Colorado School of Medicine, United States; Department of Psychiatry, University of Colorado School of Medicine, United States; Research Service, Rocky Mountain Regional VA Medical Center, United States.
Neurosci Biobehav Rev. 2019 Aug;103:414-424. doi: 10.1016/j.neubiorev.2019.06.002. Epub 2019 Jun 15.
Insula dysfunction contributes to nicotine use disorders. Yet, much remains unknown about how insular functions promote nicotine use. We review current models of brain networks in smoking and propose an extension to those models that emphasizes the role of the insula in craving. During acute withdrawal, the insula provides the sensation of craving to the cerebrum and is thought to negotiate craving sensations with cognitive control to guide behavior - either to smoke or abstain. Recent studies have shown that insula processing is saturable, such that different insular functions compete for limited resources. We propose that this saturability explains how craving during withdrawal can overload insular processing to the exclusion of other functions, such as saliency and network homeostasis. A novel signal flow model illustrates how limited insular capacity leads to breakdown of normal function. Finally, we discuss suitability of insula as a neuromodulation target to promote cessation. Given the limited efficacy of standard-of-care treatments for nicotine use disorder, insular neuromodulation offers an innovative, potentially therapeutic target for improving smoking cessation.
脑岛功能障碍导致尼古丁使用障碍。然而，对于脑岛功能如何促进尼古丁使用，我们仍然知之甚少。我们回顾了吸烟相关的大脑网络的现有模型，并对这些模型进行了扩展，强调了脑岛在渴望感中的作用。在急性戒断期间，脑岛将渴望感传递给大脑，并被认为通过认知控制来协商渴望感，以指导行为——吸烟或戒断。最近的研究表明，脑岛处理是饱和的，因此不同的脑岛功能会争夺有限的资源。我们提出，这种饱和度解释了为什么戒断期间的渴望感会使脑岛处理过载，从而排除其他功能，如突显和网络内稳态。一个新的信号流模型说明了有限的脑岛容量如何导致正常功能的崩溃。最后，我们讨论了将脑岛作为神经调节靶点促进戒烟的适用性。鉴于尼古丁使用障碍的标准治疗方法效果有限，脑岛神经调节为改善戒烟提供了一个创新的、有潜在治疗作用的靶点。
