Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark.
Aarhus Institute of Advanced Studies (AIAS), Aarhus University, Aarhus, Denmark.
Eur J Neurosci. 2022 Nov;56(10):5810-5822. doi: 10.1111/ejn.15820. Epub 2022 Sep 26.
In the search for the neural correlates of consciousness, it is often assumed that there is a stable set within the relevant sensory modality. Within the visual modality, the debate has centred upon whether frontal or occipital activations are the best predictors of perceptual awareness. Although not accepted by all as definitive evidence, no-report and decoding studies have indicated that occipital activity is the most consistently correlated with perceptual awareness whereas frontal activity might be closely related to aspects of cognition typically related to reports. However, perception is rarely just passive perception of something, but more or less always perception for something. That is, the task at hand for the perceiver may influence what is being perceived. This suggests an alternative view: that consciousness is not one specific 'function' that can be localized consistently to one area or event-related component and that the specific attributes of the neural correlates of consciousness depend on the task at hand. To investigate whether and how tasks may influence the neural correlates of consciousness, we here contrasted two tasks, a perceptual task and a conceptual task, using identical stimuli in both tasks. Using magnetoencephalography, we found that the perceptual task recruited more occipital resources than the conceptual task. Furthermore, we found that between the two conditions, the amount of frontal resources recruited differed between different gradations of perceptual awareness partly in an unexpected manner. These findings support a view of task affecting the neural correlates of consciousness.
在寻找意识的神经相关物时,通常假设在相关感觉模态内存在一个稳定的集合。在视觉模态中,争论的焦点是额叶或枕叶激活哪个是感知意识的最佳预测因子。虽然没有被所有人接受为明确的证据,但无报告和解码研究表明,枕叶活动与感知意识最相关,而额叶活动可能与通常与报告相关的认知方面密切相关。然而,感知很少只是对某物的被动感知,而是或多或少总是对某物的感知。也就是说,感知者手头的任务可能会影响被感知的内容。这表明了一种替代观点:意识不是一种可以始终如一地定位到一个区域或事件相关成分的特定“功能”,意识的神经相关物的特定属性取决于手头的任务。为了研究任务是否以及如何影响意识的神经相关物,我们在这里对比了两个任务,一个是感知任务,一个是概念任务,两个任务都使用相同的刺激。使用脑磁图,我们发现感知任务比概念任务招募了更多的枕叶资源。此外,我们发现,在两种情况下,不同程度的感知意识之间,招募的额叶资源数量存在部分意外的差异。这些发现支持了任务影响意识的神经相关物的观点。