Crossmodal Association of Visual and Haptic Material Properties of Objects in the Monkey Ventral Visual Cortex
Crossmodal Association of Visual and Haptic Material Properties of Objects in the Monkey Ventral Visual Cortex
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DOI：
10.1016/j.cub.2016.02.003
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发表时间：
2016-04-04
期刊：
影响因子：
9.2
通讯作者：
Komatsu, Hidehiko
中科院分区：
文献类型：
--
作者：
Goda, Naokazu;Yokoi, Isao;Komatsu, Hidehiko
仅仅通过观察一个物体，我们就可以识别它的非视觉属性，比如硬度。非视觉对象属性的视觉识别通常是准确的[1]，并影响对对象的行为[2]。最近的研究表明，在灵长类动物的大脑中，这可能涉及腹侧视觉皮层，它以一种不仅反映视觉而且反映非视觉对象属性的方式来表示对象，例如触觉粗糙度，硬度和重量[3-7]。这一新发现提出了一个根本性的问题：视觉皮层是如何表现非视觉属性的？这些非视觉属性是不能通过视觉直接获得的。在这里，我们解决了这个悬而未决的问题，使用功能磁共振成像在猕猴。具体来说，我们探索了简单的视觉触觉体验--仅仅看到和触摸由各种材料制成的物体--是否以及如何在视觉皮层中塑造表征内容。我们测量了猴子获得视觉-触觉体验之前和之后通过观看物体图像诱发的大脑活动，并从活动模式中解码表征空间[8]。我们发现，简单的长期视觉-触觉体验极大地影响了后下颞叶皮层和更高的腹侧视觉皮层的表征。在体验之后，而不是之前，在这个区域的活动模式很好地反映了触觉材料的属性的经验对象。我们的研究结果表明，在视觉皮层的非视觉对象属性的神经表征出现通过长期的跨模态暴露的对象。这突出了通过日常经验[9-12]进行跨模态关联的无监督学习对于塑造视觉皮层中的表征的重要性。
Just by looking at an object, wecan recognize its non-visual properties, such as hardness. The visual recognition of non-visual object properties is generally accurate [1], and influences actions toward the object [2]. Recent studies suggest that, in the primate brain, this may involve the ventral visual cortex, which represents objects in a way that reflects not only visual but also non-visual object properties, such as haptic roughness, hardness, and weight [3-7]. This new insight raises a fundamental question: how does the visual cortex come to represent non-visual properties-knowledge that cannot be acquired directly through vision? Here we addressed this unresolved question using fMRI in macaque monkeys. Specifically, we explored whether and how simple visuohaptic experience-just seeing and touching objects made of various materials-can shape representational content in the visual cortex. We measured brain activity evoked by viewing images of objects before and after the monkeys acquired the visuo-haptic experience and decoded the representational space from the activity patterns [8]. We show that simple long-term visuo-haptic experience greatly impacts representation in the posterior inferior temporal cortex, the higher ventral visual cortex. After the experience, but not before, the activity pattern in this region well reflected the haptic material properties of the experienced objects. Our results suggest that neural representation of non-visual object properties in the visual cortex emerges through long-term crossmodal exposure to objects. This highlights the importance of unsupervised learning of crossmodal associations through everyday experience [9-12] for shaping representation in the visual cortex.