van Elk Michiel, Lenggenhager Bigna, Heydrich Lukas, Blanke Olaf
Laboratory of Cognitive Neuroscience, Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Switzerland; Department of Psychology, University of Amsterdam, The Netherlands.
Neuropsychology Unit, Neurology Department, University Hospital of Zurich, Switzerland.
Biol Psychol. 2014 May;99:172-82. doi: 10.1016/j.biopsycho.2014.03.004. Epub 2014 Mar 26.
Although many studies have elucidated the neurocognitive mechanisms supporting the processing of externally generated sensory signals, less is known about the processing of interoceptive signals related to the viscera. Drawing a parallel with research on agency and the perception of self-generated action effects, in the present EEG study we report a reduced auditory N1 component when participants listened to heartbeat-related sounds compared to externally generated sounds. The auditory suppression for heartbeat sounds was robust and persisted after controlling for ECG-related artifacts, the number of trials involved and the phase of the cardiac cycle. In addition, the auditory N1 suppression for heartbeat-related sounds had a comparable scalp distribution as the N1 suppression observed for actively generated sounds. This finding indicates that the brain automatically differentiates between heartbeat-related and externally generated sounds through a process of sensory suppression, suggesting that a comparable predictive mechanism may underlie the processing of heartbeat and action-related information. Extending recent behavioral data about cardio-visual integration, the present cardio-auditory EEG data reveal that the processing of sounds in auditory cortex is systematically modulated by an interoceptive cardiac signal. The findings are discussed with respect to theories of interoceptive awareness, emotion, predictive coding, and their relevance to bodily self-consciousness.
尽管许多研究已经阐明了支持外部产生的感觉信号处理的神经认知机制，但对于与内脏相关的内感受信号的处理了解较少。与关于能动性和自我产生的动作效果感知的研究相类比，在本脑电图研究中，我们报告称，与外部产生的声音相比，参与者在听到与心跳相关的声音时，听觉N1成分有所减少。对心跳声音的听觉抑制很强，在控制了与心电图相关的伪迹、所涉及的试验次数和心动周期阶段后仍然存在。此外，对与心跳相关声音的听觉N1抑制在头皮分布上与对主动产生声音所观察到的N1抑制相当。这一发现表明，大脑通过感觉抑制过程自动区分与心跳相关的声音和外部产生的声音，这表明一种类似的预测机制可能是心跳和动作相关信息处理的基础。扩展最近关于心脏-视觉整合的行为数据，目前的心脏-听觉脑电图数据表明，听觉皮层中声音的处理受到内感受心脏信号的系统调节。我们从内感受觉知、情绪、预测编码的理论及其与身体自我意识的相关性方面对这些发现进行了讨论。
