Institute of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Institute of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China.
Cell Rep. 2023 Oct 31;42(10):113242. doi: 10.1016/j.celrep.2023.113242. Epub 2023 Oct 12.
Visual imagery allows for the construction of rich internal experience in our mental world. However, it has remained poorly understood how imagery experience derives volitionally as opposed to being cue driven. Here, using electroencephalography and functional magnetic resonance imaging, we systematically investigate the spatiotemporal dynamics of self-generated imagery by having participants volitionally imagining one of the orientations from a learned pool. We contrast self-generated imagery with cue-induced imagery, where participants imagined line orientations based on associative cues acquired previously. Our results reveal overlapping neural signatures of cue-induced and self-generated imagery. Yet, these neural signatures display substantially differential sensitivities to the two types of imagery: self-generated imagery is supported by an enhanced involvement of the anterior cortex in representing imagery contents. By contrast, cue-induced imagery is supported by enhanced imagery representations in the posterior visual cortex. These results jointly support a reverse cortical hierarchy in generating and maintaining imagery contents in self-generated versus externally cued imagery.
视觉意象可以在我们的精神世界中构建丰富的内部体验。然而，意象体验如何具有意志性而不是由线索驱动，这仍然理解得很差。在这里，我们使用脑电图和功能磁共振成像，通过让参与者自愿想象从已学习的集合中选择的一个方向，系统地研究自我产生意象的时空动态。我们将自我产生的意象与提示诱导的意象进行对比，参与者根据先前获得的联想提示来想象线条方向。我们的结果揭示了提示诱导和自我产生意象的重叠神经特征。然而，这些神经特征对这两种类型的意象显示出明显不同的敏感性：自我产生的意象表现为前皮质在代表意象内容方面的参与度增强。相比之下，提示诱导的意象则由后视觉皮层中的增强的意象表示来支持。这些结果共同支持在自我产生的意象与外部提示的意象之间，生成和维持意象内容的反向皮质层次结构。
