Centanino Valeria, Fortunato Gianfranco, Bueti Domenica
International School for Advanced Studies (SISSA), Trieste, Italy.
Nat Commun. 2024 Dec 27;15(1):10720. doi: 10.1038/s41467-024-54336-5.
Integrating spatial and temporal information is essential for our sensory experience. While psychophysical evidence suggests spatial dependencies in duration perception, few studies have directly tested the neural link between temporal and spatial processing. Using ultra-high-field functional MRI and neuronal-based modeling, we investigated how and where the processing and the representation of a visual stimulus duration is linked to that of its spatial location. Our results show a transition in duration coding: from monotonic and spatially-dependent in early visual cortex to unimodal and spatially-invariant in frontal cortex. Along the dorsal visual stream, particularly in the intraparietal sulcus (IPS), neuronal populations show common selective responses to both spatial and temporal information. In the IPS, spatial and temporal topographic organizations are also linked, although duration maps are smaller, less clustered, and more variable across participants. These findings help identify the mechanisms underlying human perception of visual duration and characterize the functional link between time and space processing, highlighting the importance of their interactions in shaping brain responses.
整合空间和时间信息对我们的感官体验至关重要。虽然心理物理学证据表明在持续时间感知中存在空间依赖性,但很少有研究直接测试时间和空间处理之间的神经联系。我们使用超高场功能磁共振成像和基于神经元的模型,研究了视觉刺激持续时间的处理和表征如何以及在何处与其空间位置的处理和表征相关联。我们的结果显示了持续时间编码的转变:从早期视觉皮层中的单调且空间依赖型,转变为额叶皮层中的单峰且空间不变型。沿着背侧视觉通路,特别是在顶内沟(IPS),神经元群体对空间和时间信息均表现出共同的选择性反应。在顶内沟中,空间和时间拓扑组织也相互关联,尽管持续时间图谱较小,聚类性较差,且在不同参与者之间变化更大。这些发现有助于确定人类视觉持续时间感知的潜在机制,并表征时间和空间处理之间的功能联系,突出了它们在塑造大脑反应中的相互作用的重要性。