Northoff Georg, Klar Philipp, Bein Magnus, Safron Adam
Mind, Brain Imaging and Neuroethics Research Unit, TheRoyal's Institute of Mental Health Research, University of Ottawa, Ottawa, ON, Canada K1Z 7K4.
Mental Health Centre, Zhejiang University School of Medicine, Hangzhou 310053, People's Republic of China.
Interface Focus. 2023 Apr 14;13(3):20220076. doi: 10.1098/rsfs.2022.0076. eCollection 2023 Jun 6.
Consciousness is constituted by a structure that includes contents as foreground and the environment as background. This structural relation between the experiential foreground and background presupposes a relationship between the brain and the environment, often neglected in theories of consciousness. The temporo-spatial theory of consciousness addresses the brain-environment relation by a concept labelled 'temporo-spatial alignment'. Briefly, temporo-spatial alignment refers to the brain's neuronal activity's interaction with and adaption to interoceptive bodily and exteroceptive environmental stimuli, including their symmetry as key for consciousness. Combining theory and empirical data, this article attempts to demonstrate the yet unclear neuro-phenomenal mechanisms of temporo-spatial alignment. First, we suggest three neuronal layers of the brain's temporo-spatial alignment to the environment. These neuronal layers span across a continuum from longer to shorter timescales. (i) The background layer comprises longer and more powerful timescales mediating topographic-dynamic similarities between different subjects' brains. (ii) The intermediate layer includes a mixture of medium-scaled timescales allowing for stochastic matching between environmental inputs and neuronal activity through the brain's intrinsic neuronal timescales and temporal receptive windows. (iii) The foreground layer comprises shorter and less powerful timescales for neuronal entrainment of stimuli temporal onset through neuronal phase shifting and resetting. Second, we elaborate on how the three neuronal layers of temporo-spatial alignment correspond to their respective phenomenal layers of consciousness. (i) The inter-subjectively shared contextual background of consciousness. (ii) An intermediate layer that mediates the relationship between different contents of consciousness. (iii) A foreground layer that includes specific fast-changing contents of consciousness. Overall, temporo-spatial alignment may provide a mechanism whose different neuronal layers modulate corresponding phenomenal layers of consciousness. Temporo-spatial alignment can provide a bridging principle for linking physical-energetic (free energy), dynamic (symmetry), neuronal (three layers of distinct time-space scales) and phenomenal (form featured by background-intermediate-foreground) mechanisms of consciousness.
意识由一种结构构成，该结构将内容作为前景，环境作为背景。体验性前景与背景之间的这种结构关系预设了大脑与环境之间的一种关系，而这种关系在意识理论中常常被忽视。意识的时空理论通过一个名为“时空对齐”的概念来探讨大脑与环境的关系。简而言之，时空对齐指的是大脑神经元活动与内感受性身体和外感受性环境刺激的相互作用及适应，包括它们的对称性是意识的关键。结合理论和实证数据，本文试图阐明时空对齐尚不明确的神经现象机制。首先，我们提出大脑与环境的时空对齐存在三个神经元层。这些神经元层跨越从较长到较短时间尺度的连续统一体。（i）背景层包含更长且更强有力的时间尺度，介导不同主体大脑之间的地形动力学相似性。（ii）中间层包括中等尺度时间尺度的混合，通过大脑内在的神经元时间尺度和时间感受窗口，允许环境输入与神经元活动之间进行随机匹配。（iii）前景层包含较短且较无力的时间尺度，用于通过神经元相位移动和重置对刺激时间起始进行神经元同步化。其次，我们详细阐述时空对齐的三个神经元层如何对应于它们各自的意识现象层。（i）意识的主体间共享情境背景。（ii）介导意识不同内容之间关系的中间层。（iii）包括特定快速变化的意识内容的前景层。总体而言，时空对齐可能提供一种机制，其不同的神经元层调节相应的意识现象层。时空对齐可为连接意识的物理能量（自由能量）、动态（对称性）、神经元（三层不同的时空尺度）和现象（以背景 - 中间 - 前景为特征的形式）机制提供一个桥梁原则。
