Georgiewa Petra, Szczepek Agnieszka J, Rose Matthias, Klapp Burghard F, Mazurek Birgit
Tinnitus Center, Charitx00E9; - Universitx00E4;tsmedizin Berlin, Berlin, Germany.
Audiol Neurootol. 2016;21(2):80-7. doi: 10.1159/000443364. Epub 2016 Feb 27.
This exploratory study determined the activation pattern in nonauditory brain areas in response to acoustic, emotionally positive, negative or neutral stimuli presented to tinnitus patients and control subjects. Ten patients with chronic tinnitus and without measurable hearing loss and 13 matched control subjects were included in the study and subjected to fMRI with a 1.5-tesla scanner. During the scanning procedure, acoustic stimuli of different emotional value were presented to the subjects. Statistical analyses were performed using statistical parametric mapping (SPM 99). The activation pattern induced by emotionally loaded acoustic stimuli differed significantly within and between both groups tested, depending on the kind of stimuli used. Within-group differences included the limbic system, prefrontal regions, temporal association cortices and striatal regions. Tinnitus patients had a pronounced involvement of limbic regions involved in the processing of chimes (positive stimulus) and neutral words (neutral stimulus), strongly suggesting improperly functioning inhibitory mechanisms that were functioning well in the control subjects. This study supports the hypothesis about the existence of a tinnitus-specific brain network. Such a network could respond to any acoustic stimuli by activating limbic areas involved in stress reactivity and emotional processing and by reducing activation of areas responsible for attention and acoustic filtering (thalamus, frontal regions), possibly reinforcing negative effects of tinnitus.
这项探索性研究确定了耳鸣患者和对照受试者在面对呈现的听觉、情绪积极、消极或中性刺激时非听觉脑区的激活模式。研究纳入了10名患有慢性耳鸣且无听力损失的患者以及13名匹配的对照受试者，并使用1.5特斯拉扫描仪对他们进行功能磁共振成像（fMRI）检查。在扫描过程中，向受试者呈现不同情绪价值的听觉刺激。使用统计参数映射（SPM 99）进行统计分析。根据所使用的刺激类型，两组受试者内部和之间由带有情绪负荷的听觉刺激诱发的激活模式存在显著差异。组内差异包括边缘系统、前额叶区域、颞叶联合皮质和纹状体区域。耳鸣患者在处理钟声（积极刺激）和中性词（中性刺激）时边缘区域有明显参与，这强烈表明抑制机制功能异常，而在对照受试者中这些机制功能正常。这项研究支持了关于存在耳鸣特异性脑网络的假说。这样一个网络可能通过激活参与应激反应和情绪处理的边缘区域以及减少负责注意力和听觉过滤的区域（丘脑、额叶区域）的激活来对任何听觉刺激做出反应，这可能会增强耳鸣的负面影响。
