Chen Feifan, Yasoda-Mohan Anusha, Sé Colum Ó, Vanneste Sven
Lab for Clinical and Integrative Neuroscience, Trinity College Institute for Neuroscience, School of Psychology, Trinity College Dublin, Dublin, Ireland.
Global Brain Health Institute, Trinity College Dublin, Dublin, Ireland.
Imaging Neurosci (Camb). 2025 May 9;3. doi: 10.1162/imag_a_00574. eCollection 2025.
Auditory phantom perception, exemplified by tinnitus, is characterized by a perceptual experience without external stimuli. This study utilized two auditory illusions, the Zwicker Tone (ZT) and Conditioned Hallucinations (CH), as proxies to investigate the neural correlates of bottom-up and top-down mechanisms underlying phantom auditory perception. Using a within-subject design, ZT, driven by temporary sensory deficits, and CH, influenced by multisensory expectations, were examined in a sample of healthy participants. Electrophysiological measures revealed distinct time-frequency patterns, with increased theta activity in central regions during ZT perception but decreased parietal theta power during CH perception. Key regions in the ZT network, including the medial prefrontal cortex, lateral orbitofrontal cortex, and ventral posterior cingulate cortex, suggested the involvement of the default mode network and predictive processing in compensating for sensory deficits. In contrast, CH perception implicated the parahippocampus, entorhinal cortex, and inferior temporal gyrus in modulating multisensory associations and cognitive expectations. Taken together, this study revealed the neural mechanism of two auditory illusions, which enhances understanding of tinnitus mechanism. The results also highlight potential neural targets for neuromodulation interventions addressing both sensory and cognitive components of chronic phantom perception.
以耳鸣为代表的听觉幻听，其特征是在没有外部刺激的情况下产生感知体验。本研究利用两种听觉错觉，即齐克纳音调（ZT）和条件性幻觉（CH），作为探究幻听感知背后自下而上和自上而下机制的神经关联的替代指标。采用被试内设计，在健康参与者样本中对由暂时性感觉缺陷驱动的ZT和受多感官预期影响的CH进行了研究。电生理测量揭示了不同的时频模式，在ZT感知期间中央区域的θ活动增加，而在CH感知期间顶叶θ功率降低。ZT网络中的关键区域，包括内侧前额叶皮质、外侧眶额皮质和腹侧后扣带回皮质，表明默认模式网络和预测性处理参与了对感觉缺陷的补偿。相比之下，CH感知涉及海马旁回、内嗅皮质和颞下回在调节多感官关联和认知预期方面的作用。综上所述，本研究揭示了两种听觉错觉的神经机制，这增进了对耳鸣机制的理解。研究结果还突出了针对慢性幻听感知的感觉和认知成分的神经调节干预的潜在神经靶点。
