Mirz F, Pedersen B, Ishizu K, Johannsen P, Ovesen T, Stødkilde-Jørgensen H, Gjedde A
Department of Otorhinolaryngology, Aarhus University Hospital, Denmark.
Hear Res. 1999 Aug;134(1-2):133-44. doi: 10.1016/s0378-5955(99)00075-1.
Tinnitus is associated with a wide variety of disorders in the auditory system. Whether generated peripherally or centrally, tinnitus is believed to be associated with activity in specific cortical regions. The present study tested the hypothesis that these cortical centers subserve the generation, perception and processing of the tinnitus stimulus and that these processes are suppressed by lidocaine and masking. Positron emission tomography was used to map the tinnitus-specific central activity. By subtracting positron emission tomography images of regional cerebral blood flow distribution obtained during suppression of the tinnitus from positron emission tomography images obtained during the habitual tinnitus sensation, we were able to identify brain areas concerned with the cerebral representation of tinnitus. Increased neuronal activity caused by tinnitus occurred predominantly in the right hemisphere with significant foci in the middle frontal and middle temporal gyri, in addition to lateral and mesial posterior sites. The results are consistent with the hypothesis that the sensation of tinnitus is associated with activity in cortical regions functionally linked to subserve attention, emotion and memory. For the first time, the functional anatomy of conditions with and without the habitual tinnitus sensation was obtained and compared in the same subjects.
耳鸣与听觉系统的多种疾病相关。无论耳鸣是外周产生还是中枢产生，人们认为它都与特定皮质区域的活动有关。本研究检验了以下假设：这些皮质中枢参与耳鸣刺激的产生、感知和处理，并且这些过程会被利多卡因和掩蔽所抑制。采用正电子发射断层扫描来描绘耳鸣特异性的中枢活动。通过将习惯性耳鸣感觉期间获得的正电子发射断层扫描图像中区域脑血流分布图像，与耳鸣抑制期间获得的正电子发射断层扫描图像相减，我们能够识别与耳鸣脑表征相关的脑区。耳鸣引起的神经元活动增加主要发生在右半球，在额中回和颞中回有明显的病灶，此外还有外侧和内侧后部区域。这些结果与以下假设一致，即耳鸣的感觉与皮质区域的活动有关，这些皮质区域在功能上与注意力、情绪和记忆相关。首次在同一受试者中获得并比较了有和没有习惯性耳鸣感觉的情况下的功能解剖结构。
