Current theories of visual consciousness disagree about whether it emerges during early stages of processing in sensory brain regions or later when a widespread frontoparietal network becomes involved. Moreover, disentangling conscious perception from task-related postperceptual processes (e.g., report) and integrating results across different neuroscientific methods remain ongoing challenges. The present study addressed these problems using simultaneous EEG-fMRI and a specific inattentional blindness paradigm with three physically identical phases in female and male human participants. In phase 1, participants performed a distractor task during which line drawings of faces and control stimuli were presented centrally. While some participants spontaneously noticed the faces in phase 1, others remained inattentionally blind. In phase 2, all participants were made aware of the task-irrelevant faces but continued the distractor task. In phase 3, the faces became task-relevant. Bayesian analysis of brain responses demonstrated that conscious face perception was most strongly associated with activation in fusiform gyrus (fMRI) as well as the N170 and visual awareness negativity (EEG). Smaller awareness effects were revealed in the occipital and prefrontal cortex (fMRI). Task-relevant face processing, on the other hand, led to strong, extensive activation of occipitotemporal, frontoparietal, and attentional networks (fMRI). In EEG, it enhanced early negativities and elicited a pronounced P3b component. Overall, we provide evidence that conscious visual perception is linked with early processing in stimulus-specific sensory brain areas but may additionally involve prefrontal cortex. In contrast, the strong activation of widespread brain networks and the P3b are more likely associated with task-related processes.

SIGNIFICANCE STATEMENT How does our brain generate visual consciousness—the subjective experience of what it is like to see, for example, a face? To date, it is hotly debated whether it emerges early in sensory brain regions or later when a widespread frontoparietal network is activated. Here, we use simultaneous fMRI and EEG for high spatial and temporal resolution and demonstrate that conscious face perception is predominantly linked to early and occipitotemporal processes, but also prefrontal activity. Task-related processes (e.g., decision-making), on the other hand, elicit brain-wide activations including late and strong frontoparietal activity. These findings challenge numerous previous studies and highlight the importance of investigating the neural correlates of consciousness in the absence of task relevance.

当前的视觉意识理论不同意它是在感觉大脑区域的早期处理阶段出现，还是在广泛的额顶网络参与之后出现。此外，从与任务相关的后知觉过程（例如，报告）中解开意识知觉和整合不同神经科学方法的结果仍然是持续的挑战。本研究使用同步 EEG-fMRI 和特定的无意失明范式，在女性和男性参与者的三个身体相同的阶段解决了这些问题。在第一阶段，参与者执行了一项分散注意力的任务，在此期间，面部线条图和控制刺激被集中呈现。虽然一些参与者自发地注意到了第一阶段的面孔，但其他人仍然不经意间失明。在第 2 阶段，所有参与者都知道与任务无关的面孔，但继续干扰任务。在第 3 阶段，面孔变得与任务相关。对大脑反应的贝叶斯分析表明，有意识的面部感知与梭状回 (fMRI) 以及 N170 和视觉意识负性 (EEG) 的激活最密切相关。在枕叶和前额叶皮层 (fMRI) 中显示出较小的意识效应。另一方面，与任务相关的面部处理导致枕颞、额顶和注意力网络 (fMRI) 的强烈、广泛激活。在 EEG 中，它增强了早期阴性并引发了明显的 P3b 成分。总体而言，我们提供的证据表明，有意识的视觉感知与刺激特定的感觉大脑区域的早期处理有关，但可能还涉及前额叶皮层。

意义陈述我们的大脑如何产生视觉意识——例如看到一张脸的主观体验？迄今为止，它是在大脑感觉区域的早期出现还是在广泛的额顶网络被激活时出现，这一点一直存在激烈争论。在这里，我们同时使用 fMRI 和 EEG 来获得高空间和时间分辨率，并证明有意识的面部感知主要与早期和枕颞过程有关，但也与前额叶活动有关。另一方面，与任务相关的过程（例如，决策）会引起全脑激活，包括晚期和强烈的额顶活动。这些发现挑战了许多先前的研究，并强调了在缺乏任务相关性的情况下调查意识的神经相关性的重要性。