Institute of Medical Psychology and Systems Neuroscience, University of Münster, Von-Esmarch-Str. 52, 48149, Münster, Germany.
Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Münster, Fliednerstr. 21, 48149, Münster, Germany.
Sci Rep. 2024 May 8;14(1):10593. doi: 10.1038/s41598-024-61281-2.
Previous research on the neural correlates of consciousness (NCC) in visual perception revealed an early event-related potential (ERP), the visual awareness negativity (VAN), to be associated with stimulus awareness. However, due to the use of brief stimulus presentations in previous studies, it remains unclear whether awareness-related negativities represent a transient onset-related response or correspond to the duration of a conscious percept. Studies are required that allow prolonged stimulus presentation under aware and unaware conditions. The present ERP study aimed to tackle this challenge by using a novel stimulation design. Male and female human participants (n = 62) performed a visual task while task-irrelevant line stimuli were presented in the background for either 500 or 1000 ms. The line stimuli sometimes contained a face, which needed so-called visual one-shot learning to be seen. Half of the participants were informed about the presence of the face, resulting in faces being perceived by the informed but not by the uninformed participants. Comparing ERPs between the informed and uninformed group revealed an enhanced negativity over occipitotemporal electrodes that persisted for the entire duration of stimulus presentation. Our results suggest that sustained visual awareness negativities (SVAN) are associated with the duration of stimulus presentation.
先前关于视觉感知意识神经相关物（NCC）的研究揭示了一个早期的事件相关电位（ERP），即视觉意识负波（VAN），与刺激意识有关。然而，由于先前的研究中使用了短暂的刺激呈现，因此尚不清楚与意识相关的负波是否代表一种短暂的起始相关反应，或者是否与意识知觉的持续时间相对应。需要进行研究以允许在有意识和无意识条件下进行长时间的刺激呈现。本项 ERP 研究旨在通过使用新的刺激设计来解决这一挑战。男性和女性人类参与者（n=62）在执行视觉任务的同时，在背景中呈现了任务无关的线刺激，呈现时间为 500 或 1000 毫秒。这些线刺激有时包含一张脸，需要所谓的视觉单次学习才能看到。一半的参与者被告知脸的存在，结果是知情参与者能够看到脸，而不知情参与者则看不到。将知情组和不知情组的 ERP 进行比较，发现枕颞电极上的负性增强持续存在于整个刺激呈现期间。我们的结果表明，持续的视觉意识负波（SVAN）与刺激呈现的持续时间有关。
