Transformations of sensory information in the brain reflect a changing definition of optimality.
Transformations of sensory information in the brain reflect a changing definition of optimality.
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大脑中感觉信息的转变反映了最优性定义的变化。
DOI：
10.1101/2023.03.24.534044
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发表时间：
2023
期刊：
影响因子：
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通讯作者：
Cooper,EmilyA
中科院分区：
文献类型：
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作者：
Manning,TylerS;Alexander,Emma;Cumming,BruceG;DeAngelis,GregoryC;Huang,Xin;Cooper,EmilyA
整个大脑的神经元都会合法地调整它们的放电率，以应对感觉输入的变化。神经计算理论认为，这些调制反映了受限优化的结果：神经元的目标是在资源有限的情况下高效而稳健地表示感觉信息。然而，我们对这种优化在整个大脑中如何变化的理解仍处于初级阶段。在这里，我们展示了神经反应沿着视觉系统的背部流以一种与从优化信息保存到优化感知辨别的转变一致的方式转换。聚焦于双眼视差-物体如何投射到双眼上的微小差异-我们重新分析了猕猴大脑区域V1、V2和MT中表征调谐曲线的神经元的测量结果，并将这些测量结果与双眼视差的自然视觉统计数据的测量结果进行了比较。调谐曲线特性的变化在计算上与优化目标从最大化关于自然发生的双目视差的编码信息到最大化支持精细视差辨别的能力的转变是一致的。我们发现，倾向于调整曲线而不是更大的差异是这种转变的关键驱动因素。这些结果为之前发现的皮质视差选择性区域之间的差异提供了新的见解，并表明这些差异在支持视觉引导行为方面发挥了重要作用。我们的发现支持对大脑中包含感觉信息的区域进行最佳编码的关键重新构建，强调不仅需要考虑信息保存和神经资源，而且需要考虑与行为的相关性。
Neurons throughout the brain modulate their firing rate lawfully in response to changes in sensory input. Theories of neural computation posit that these modulations reflect the outcome of a constrained optimization: neurons aim to efficiently and robustly represent sensory information under resource limitations. Our understanding of how this optimization varies across the brain, however, is still in its infancy. Here, we show that neural responses transform along the dorsal stream of the visual system in a manner consistent with a transition from optimizing for information preservation to optimizing for perceptual discrimination. Focusing on binocular disparity – the slight differences in how objects project to the two eyes – we re-analyze measurements from neurons characterizing tuning curves in macaque monkey brain regions V1, V2, and MT, and compare these to measurements of the natural visual statistics of binocular disparity. The changes in tuning curve characteristics are computationally consistent with a shift in optimization goals from maximizing the information encoded about naturally occurring binocular disparities to maximizing the ability to support fine disparity discrimination. We find that a change towards tuning curves preferring larger disparities is a key driver of this shift. These results provide new insight into previously-identified differences between disparity-selective regions of cortex and suggest these differences play an important role in supporting visually-guided behavior. Our findings support a key re-framing of optimal coding in regions of the brain that contain sensory information, emphasizing the need to consider not just information preservation and neural resources, but also relevance to behavior.