Initial-state-dependent, robust, transient neural dynamics encode conscious visual perception.
Initial-state-dependent, robust, transient neural dynamics encode conscious visual perception.
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DOI：
10.1371/journal.pcbi.1005806
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发表时间：
2017-11
影响因子：
4.3
通讯作者：
He BJ
中科院分区：
文献类型：
--
作者：
Baria AT;Maniscalco B;He BJ
最近的研究已经确定了延迟，持久的神经活动作为一个强大的相关性的意识知觉。然而，这种活动的动力学性质知之甚少，其存在或不存在的机制以及相关的意识感知仍然难以捉摸。我们将动态模式分析应用于由脑磁图（MEG）记录的人类受试者执行阈值水平视觉感知任务的全脑慢（< 5 Hz）皮质动力学。刺激开始前1秒，大脑活动模式在广泛的皮质显着预测阈值水平的视觉刺激是否后来有意识地感知。大脑活动的这种初始状态与刺激输入非线性地相互作用，以形成不断发展的皮层活动轨迹，其中可见和不可见的试验遵循分离良好的轨迹。我们观察到，在有意识的感知过程中，皮层活动轨迹是快速发展的，并且对初始状态的微小变化具有鲁棒性。此外，在看不见的试验中，刺激开始前的自发脑活动模式也会影响无意识知觉的形成。总之，这些结果表明，有意识的视觉感知的大脑动力学属于一类的初始状态依赖，强大的，瞬态的神经动力学。有意识知觉的大脑机制是什么？研究这个问题的一个普遍采用的范式是向人类受试者提供阈值水平的刺激。当重复显示时，相同的刺激有时会被有意识地感知到，有时不会。使用脑磁图，我们揭示了神经机制，是否刺激有意识地感知在一个给定的审判。我们观察到，取决于由缓慢皮层电位（<5 Hz）范围内的广泛活动模式定义的初始大脑状态，物理上相同的短暂（30-60 ms）刺激输入会随着时间的推移触发不同的活动模式演变序列，这些序列对应于有意识地感知刺激或没有感知刺激。这种活动模式的演变形成了一个“轨迹”的状态空间，并提供了显着的单次尝试解码的感知结果从1秒前到3秒后刺激开始。虽然以前关于意识感知的理论强调持续的高水平活动，但我们发现，意识感知背后的大脑动力学表现出快速变化的活动模式。这些结果显着进一步我们的神经机制，有意识的刺激和分布式神经活动的动力学性质的有意识的知觉。
Recent research has identified late-latency, long-lasting neural activity as a robust correlate of conscious perception. Yet, the dynamical nature of this activity is poorly understood, and the mechanisms governing its presence or absence and the associated conscious perception remain elusive. We applied dynamic-pattern analysis to whole-brain slow (< 5 Hz) cortical dynamics recorded by magnetoencephalography (MEG) in human subjects performing a threshold-level visual perception task. Up to 1 second before stimulus onset, brain activity pattern across widespread cortices significantly predicted whether a threshold-level visual stimulus was later consciously perceived. This initial state of brain activity interacts nonlinearly with stimulus input to shape the evolving cortical activity trajectory, with seen and unseen trials following well separated trajectories. We observed that cortical activity trajectories during conscious perception are fast evolving and robust to small variations in the initial state. In addition, spontaneous brain activity pattern prior to stimulus onset also influences unconscious perceptual making in unseen trials. Together, these results suggest that brain dynamics underlying conscious visual perception belongs to the class of initial-state-dependent, robust, transient neural dynamics. What brain mechanisms underlie conscious perception? A commonly adopted paradigm for studying this question is to present human subjects with threshold-level stimuli. When shown repeatedly, the same stimulus is sometimes consciously perceived, sometimes not. Using magnetoencephalography, we shed light on the neural mechanisms governing whether the stimulus is consciously perceived in a given trial. We observed that depending on the initial brain state defined by widespread activity pattern in the slow cortical potential (<5 Hz) range, a physically identical, brief (30–60 ms) stimulus input triggers distinct sequences of activity pattern evolution over time that correspond to either consciously perceiving the stimulus or not. Such activity pattern evolution forms a “trajectory” in the state space and affords significant single-trial decoding of perceptual outcome from 1 sec before to 3 sec after stimulus onset. While previous theories on conscious perception have emphasized sustained, high-level activity, we found that brain dynamics underlying conscious perception exhibit fast-changing activity patterns. These results significantly further our understanding on the neural mechanisms governing conscious access of a stimulus and the dynamical nature of distributed neural activity underlying conscious perception.
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影响因子：
19.9
作者：
Fiser, Jozsef;Berkes, Pietro;Orban, Gergo;Lengyel, Mate
通讯作者：
Lengyel, Mate
影响因子：
5.3
作者：
Busch, Niko A.;Dubois, Julien;VanRullen, Rufin
通讯作者：
VanRullen, Rufin
影响因子：
5.7
作者：
Dehaene S;Charles L;King JR;Marti S
通讯作者：
Marti S
影响因子：
16.2
作者：
Fisch, Lior;Privman, Eran;Ramot, Michal;Harel, Michal;Nir, Yuval;Kipervasser, Svetlana;Andelman, Fani;Neufeld, Miri Y.;Kramer, Uri;Fried, Itzhak;Malach, Rafael
通讯作者：
Malach, Rafael
影响因子：
4.3
作者：
He BJ;Zempel JM
通讯作者：
Zempel JM