Scene imagery features prominently when we recall autobiographical memories, imagine the future and navigate around in the world. Consequently, in this study we sought to better understand how scene representations are supported by the brain. Processing scenes involves a variety of cognitive processes that in the real world are highly interactive. Here, however, our goal was to separate semantic and spatial constructive scene processes in order to identify the brain areas that were distinct to each process, those they had in common, and the connectivity between regions. To this end, participants searched for either semantic or spatial constructive impossibilities in scenes during functional MRI. We focussed our analyses on only those scenes that were possible, thus removing any error detection that would evoke reactions such as surprise or novelty. Importantly, we also counterbalanced possible scenes across participants, enabling us to examine brain activity and connectivity for the same possible scene images under two different conditions. We found that participants adopted different cognitive strategies, which were reflected in distinct oculomotor behaviour, for each condition. These were in turn associated with increased engagement of lateral temporal and parietal cortices for semantic scene processing, the hippocampus for spatial constructive scene processing, and increased activation of the ventromedial prefrontal cortex (vmPFC) that was common to both. Connectivity analyses showed that the vmPFC switched between semantic and spatial constructive brain networks depending on the task at hand. These findings further highlight the well-known semantic functions of lateral temporal areas, while providing additional support for the previously-asserted contribution of the hippocampus to scene construction, and recent suggestions that the vmPFC may play a key role in orchestrating scene processing.

当我们回忆自传式记忆、想象未来和环游世界时，场景意象显得尤为突出。因此，在这项研究中，我们试图更好地理解大脑如何支持场景表征。处理场景涉及到现实世界中高度交互的各种认知过程。然而，在这里，我们的目标是将语义和空间建设性场景过程分开，以便识别每个过程独特的大脑区域、它们的共同点以及区域之间的连接性。为此，参与者在功能性 MRI 过程中寻找场景中语义或空间建设性的不可能性。我们仅将分析重点放在那些可能的场景上，从而消除了任何会引起惊讶或新奇反应的错误检测。重要的是，我们还平衡了参与者之间可能的场景，使我们能够检查两种不同条件下相同可能场景图像的大脑活动和连接性。我们发现参与者针对每种情况采取了不同的认知策略，这反映在不同的动眼行为中。这些反过来又与外侧颞叶和顶叶皮层用于语义场景处理的参与增加、海马体用于空间建设性场景处理的参与增加以及两者共有的腹内侧前额叶皮层（vmPFC）的激活增加有关。连接性分析表明，vmPFC 根据手头的任务在语义和空间建设性大脑网络之间切换。 这些发现进一步强调了外侧颞区众所周知的语义功能，同时为先前断言的海马体对场景构建的贡献以及最近提出的 vmPFC 可能在协调场景处理中发挥关键作用的建议提供了额外的支持。