PDF(Pubmed)
Abstract：
Tinnitus is a common phantom auditory percept believed to be related to plastic changes in the brain due to hearing loss. However, tinnitus can also occur in the absence of any clinical hearing loss. In this case, since there is no hearing loss, the mechanisms that drive plastic changes remain largely enigmatic. Previous studies showed subtle differences in sound-evoked brain activity associated with tinnitus in subjects with tinnitus and otherwise normal hearing, but the results are not consistent across studies. Here, we aimed to investigate these differences using monaural rather than binaural stimuli. Sound-evoked responses were measured using functional magnetic resonance imaging (MRI) in participants with and without tinnitus. All participants had clinically normal audiograms. The stimuli were pure tones with frequencies between 353 and 8000 Hz, presented monaurally. A Principal Component Analysis (PCA) of the response in the auditory cortex revealed no difference in tonotopic organization, which confirmed earlier studies. A GLM analysis showed hyperactivity in the lateral areas of the bilateral auditory cortex. Consistent with the tonotopic map, this hyperactivity mainly occurred in response to low stimulus frequencies. This may be related to hyperacusis. Furthermore, there was an interaction between stimulation side and tinnitus in the parahippocampus. This may reflect an interference between tinnitus and spatial orientation.
摘要：
耳鸣是一种常见的幻影听觉感知，被认为与听力损失引起的大脑可塑性变化有关。然而,在没有任何临床听力损失的情况下也可能发生耳鸣。在这种情况下,因为没有听力损失,推动塑料变化的机制在很大程度上仍然是神秘的。先前的研究表明，在耳鸣和其他正常听力的受试者中，与耳鸣相关的声音诱发的大脑活动存在细微差异，但研究结果并不一致.这里,我们的目的是使用单耳而不是双耳刺激来研究这些差异。使用功能磁共振成像（MRI）测量有和没有耳鸣的参与者的声音诱发反应。所有参与者都有临床正常的听力图。刺激是纯音，频率在353到8000赫兹之间，单耳呈现。对听觉皮层反应的主成分分析（PCA）显示，音调组织没有差异，这证实了早期的研究。GLM分析显示，双侧听觉皮层外侧区域活动过度。与地形图一致，这种过度活动主要发生在低刺激频率下。这可能与运动过度有关。此外，刺激侧和海马旁的耳鸣之间存在相互作用。这可能反映了耳鸣和空间取向之间的干扰。
