Department of Computational Sciences, Wigner Research Center for Physics, Budapest, 1121, Hungary.
Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
Nat Commun. 2023 Oct 21;14(1):6687. doi: 10.1038/s41467-023-42441-w.
Effective task execution requires the representation of multiple task-related variables that determine how stimuli lead to correct responses. Even the primary visual cortex (V1) represents other task-related variables such as expectations, choice, and context. However, it is unclear how V1 can flexibly accommodate these variables without interfering with visual representations. We trained mice on a context-switching cross-modal decision task, where performance depends on inferring task context. We found that the context signal that emerged in V1 was behaviorally relevant as it strongly covaried with performance, independent from movement. Importantly, this signal was integrated into V1 representation by multiplexing visual and context signals into orthogonal subspaces. In addition, auditory and choice signals were also multiplexed as these signals were orthogonal to the context representation. Thus, multiplexing allows V1 to integrate visual inputs with other sensory modalities and cognitive variables to avoid interference with the visual representation while ensuring the maintenance of task-relevant variables.
有效的任务执行需要表示多个与任务相关的变量，这些变量决定了刺激如何导致正确的反应。即使是初级视觉皮层 (V1) 也代表了其他与任务相关的变量，如期望、选择和上下文。然而，目前尚不清楚 V1 如何在不干扰视觉表示的情况下灵活适应这些变量。我们在一个上下文切换跨模态决策任务中对老鼠进行了训练，在这个任务中，表现取决于对任务上下文的推断。我们发现，V1 中出现的上下文信号与行为相关，因为它与性能高度相关，而与运动无关。重要的是，这种信号通过将视觉信号和上下文信号多路复用到正交子空间中，被整合到 V1 的表示中。此外，听觉和选择信号也被多路复用，因为这些信号与上下文表示正交。因此，多路复用允许 V1 将视觉输入与其他感觉模态和认知变量集成在一起，同时避免与视觉表示产生干扰，从而确保任务相关变量的维持。
