Clinical Neuroscience Research Unit and Brain Imaging Program, Department of Psychiatry, University of Vermont College of Medicine, Burlington, VT 05401, USA.
Biochem Pharmacol. 2011 Oct 15;82(8):943-51. doi: 10.1016/j.bcp.2011.06.008. Epub 2011 Jun 13.
Significant advances in human functional brain imaging offer new opportunities for direct observation of the effects of nicotine, novel nicotinic agonists and nicotinic antagonists on human cognitive and behavioral performance. Careful research over the last decade has enabled investigators to explore the role of nicotinic systems on the functional neuroanatomy and neural circuitry of cognitive tasks in domains such as selective attention, working memory, episodic memory, cognitive control, and emotional processing. In addition, recent progress in understanding functional connectivity between brain regions utilized during cognitive and emotional processes offers new opportunities for examining drug effects on network-related activity. This review will critically summarize available nicotinic functional brain imaging studies focusing on the specific cognitive domains of attention, memory, behavioral control, and emotional processing. Generally speaking, nicotine appears to increase task-related activity in non-smokers and deprived smokers, but not active smokers. By contrast, nicotine or nicotinic stimulation decreases the activity of structures associated with the default mode network. These particular patterns of activation and/or deactivation may be useful for early drug development and may be an efficient and cost-effective method of screening potential nicotinic agents. Further studies will have to be done to clarify whether such activity changes correlate with cognitive or affective outcomes that are clinically relevant. The use of functional brain imaging will be a key tool for probing pathologic changes related to brain illness and for nicotinic drug development.
人类功能脑成像的重大进展为直接观察尼古丁、新型烟碱激动剂和烟碱拮抗剂对人类认知和行为表现的影响提供了新的机会。过去十年的精心研究使研究人员能够探索烟碱系统在选择性注意、工作记忆、情景记忆、认知控制和情绪处理等认知任务的功能神经解剖学和神经回路中的作用。此外，对认知和情绪过程中大脑区域之间功能连接的理解的最新进展为研究药物对网络相关活动的影响提供了新的机会。这篇综述将批判性地总结现有的烟碱功能脑成像研究，重点关注注意力、记忆、行为控制和情绪处理等特定认知领域。一般来说，尼古丁似乎会增加非吸烟者和被剥夺吸烟的吸烟者的任务相关活动，但不会增加吸烟者的活动。相比之下，尼古丁或烟碱刺激会降低与默认模式网络相关的结构的活动。这些特定的激活和/或失活模式可能有助于早期药物开发，并且可能是筛选潜在烟碱剂的有效且具有成本效益的方法。需要进一步的研究来澄清这种活性变化是否与具有临床相关性的认知或情感结果相关。功能脑成像的使用将是探究与大脑疾病相关的病理变化和烟碱药物开发的关键工具。
