Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.
Wellcome Centre for Integrative Neuroimaging, University of Oxford, FMRIB, John Radcliffe Hospital, Oxford, United Kingdom.
PLoS Biol. 2020 Dec 7;18(12):e3001023. doi: 10.1371/journal.pbio.3001023. eCollection 2020 Dec.
The way we perceive the world is strongly influenced by our expectations. In line with this, much recent research has revealed that prior expectations strongly modulate sensory processing. However, the neural circuitry through which the brain integrates external sensory inputs with internal expectation signals remains unknown. In order to understand the computational architecture of the cortex, we need to investigate the way these signals flow through the cortical layers. This is crucial because the different cortical layers have distinct intra- and interregional connectivity patterns, and therefore determining which layers are involved in a cortical computation can inform us on the sources and targets of these signals. Here, we used ultra-high field (7T) functional magnetic resonance imaging (fMRI) to reveal that prior expectations evoke stimulus-specific activity selectively in the deep layers of the primary visual cortex (V1). These findings are in line with predictive processing theories proposing that neurons in the deep cortical layers represent perceptual hypotheses and thereby shed light on the computational architecture of cortex.
我们感知世界的方式受到我们预期的强烈影响。根据这一点，最近的许多研究表明，先前的预期强烈调节了感觉处理。然而，大脑将外部感觉输入与内部预期信号整合的神经回路仍然未知。为了了解皮质的计算结构，我们需要研究这些信号在皮质层中流动的方式。这是至关重要的，因为不同的皮质层具有不同的内部和区域间连接模式，因此确定哪些层参与了皮质计算，可以告诉我们这些信号的来源和目标。在这里，我们使用超高场（7T）功能磁共振成像（fMRI）来揭示先前的预期会选择性地在初级视觉皮层（V1）的深层引起与刺激特异性的活动。这些发现与预测处理理论一致，该理论提出，深层皮质层中的神经元代表感知假设，从而揭示了皮质的计算结构。
