Neuroscience Program, University of Illinois Urbana-Champaign, Champaign, IL, United States; Department of Speech and Hearing Science, University of Illinois Urbana-Champaign, Champaign, IL, United States; Beckman Institute, University of Illinois Urbana-Champaign, Champaign, IL, United States.
Department of Speech and Hearing Science, University of Illinois Urbana-Champaign, Champaign, IL, United States; Beckman Institute, University of Illinois Urbana-Champaign, Champaign, IL, United States.
Brain Res. 2014 Jun 3;1567:28-41. doi: 10.1016/j.brainres.2014.04.024. Epub 2014 Apr 23.
Although alterations of the limbic system have been linked to tinnitus persistence, the neural networks underlying such alteration are unclear. The present study investigated the effect of tinnitus on emotional processing in middle-aged adults using functional magnetic resonance imaging and stimuli from the International Affective Digital Sounds database. There were three groups of participants: bilateral hearing loss with tinnitus (TIN), age- and gender-matched controls with bilateral hearing loss without tinnitus (HL) and matched normal hearing controls without tinnitus (NH). In the scanner, subjects rated sounds as pleasant, unpleasant, or neutral. The TIN and NH groups, but not the HL group, responded faster to affective sounds compared to neutral sounds. The TIN group had elevated response in bilateral parahippocampus and right insula compared to the NH group, and left parahippocampus compared to HL controls for pleasant relative to neutral sounds. A region-of-interest analysis detected increased activation for NH controls in the right amygdala when responding to affective stimuli, but failed to find a similar heightened response in the TIN and HL groups. All three groups showed increased response in auditory cortices for the affective relative to neutral sounds comparisons. Our results suggest that the emotional processing network is altered in tinnitus to rely on the parahippocampus and insula, rather than the amygdala, and this alteration may maintain a select advantage for the rapid processing of affective stimuli despite the hearing loss. The complex interaction of tinnitus and the limbic system should be accounted for in development of new tinnitus management strategies.
尽管边缘系统的改变与耳鸣持续存在有关，但这种改变的神经网络尚不清楚。本研究使用功能磁共振成像和国际情感数字声音数据库中的刺激，调查了耳鸣对中年成年人情绪处理的影响。参与者分为三组：双侧听力损失伴耳鸣（TIN）、年龄和性别匹配的双侧听力损失无耳鸣（HL）和匹配的无耳鸣正常听力对照组（NH）。在扫描仪中，受试者将声音评为愉快、不愉快或中性。与 HL 组相比，TIN 组和 NH 组对情感声音的反应更快。与 NH 组相比，TIN 组双侧海马旁回和右侧岛叶的反应增强，与 HL 对照组相比，左侧海马旁回对愉快声音的反应增强。感兴趣区分析发现，NH 对照组在对情感刺激做出反应时，右侧杏仁核的激活增加，但 TIN 组和 HL 组没有发现类似的增强反应。三组在听觉皮层对情感声音的反应均高于中性声音。我们的研究结果表明，耳鸣患者的情绪处理网络发生改变，依赖于海马旁回和岛叶，而不是杏仁核，这种改变可能会保持对情感刺激的快速处理的选择性优势，尽管存在听力损失。在开发新的耳鸣管理策略时，应考虑耳鸣和边缘系统的复杂相互作用。
