Spatial reference frames of visual, vestibular, and multimodal heading signals in the dorsal subdivision of the medial superior temporal area
Spatial reference frames of visual, vestibular, and multimodal heading signals in the dorsal subdivision of the medial superior temporal area
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DOI：
10.1523/jneurosci.3553-06.2007
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发表时间：
2007-01-17
影响因子：
5.3
通讯作者：
Angelaki, Dora E.
中科院分区：
文献类型：
--
作者：
Fetsch, Christopher R.;Wang, Sentao;Angelaki, Dora E.
航向知觉是一项复杂的任务，通常需要视觉和前庭线索的整合。这两种模式在不同的空间参照系(视觉，以眼睛为中心；前庭，以头部为中心)中对运动进行编码的事实使这种感觉整合变得复杂。视觉和前庭方向信号汇聚在内侧上颞区(MSTd)的灵长类背侧分区，该区域被认为对方向知觉有贡献，但这些信号的参照系仍然未知。我们通过呈现光流(视觉状态)、惯性运动(前庭状态)或两种线索的一致组合(组合状态)来测量MSTd神经元的航向调谐。静态眼位因试验不同而不同，以确定调整的参照系(以眼睛为中心、以头部为中心或中间)。我们发现，对光流的调谐主要是以眼睛为中心，而对惯性运动的调谐是中等的，但更接近于以头部为中心。两种单峰条件下的参照系在单个神经元中很少匹配，并且在整个群体中不相关。值得注意的是，在综合条件下，参照系随着视觉和前庭调谐的相对强度和空间一致性而变化。这是第一次在自然主义的、多模式的条件下对空间参照系进行研究，在这种条件下，线索可以被整合以改善知觉表现。我们的结果与最近的一个神经网络模型的预测相比是有利的，该模型使用递归结构来执行最佳线索整合，这表明大脑可以使用类似的计算策略来整合以不同参照系表示的感觉信号。
Heading perception is a complex task that generally requires the integration of visual and vestibular cues. This sensory integration is complicated by the fact that these two modalities encode motion in distinct spatial reference frames (visual, eye-centered; vestibular, head-centered). Visual and vestibular heading signals converge in the primate dorsal subdivision of the medial superior temporal area (MSTd), a region thought to contribute to heading perception, but the reference frames of these signals remain unknown. We measured the heading tuning of MSTd neurons by presenting optic flow (visual condition), inertial motion (vestibular condition), or a congruent combination of both cues (combined condition). Static eye position was varied from trial to trial to determine the reference frame of tuning (eye-centered, head-centered, or intermediate). We found that tuning for optic flow was predominantly eye-centered, whereas tuning for inertial motion was intermediate but closer to head-centered. Reference frames in the two unimodal conditions were rarely matched in single neurons and uncorrelated across the population. Notably, reference frames in the combined condition varied as a function of the relative strength and spatial congruency of visual and vestibular tuning. This represents the first investigation of spatial reference frames in a naturalistic, multimodal condition in which cues may be integrated to improve perceptual performance. Our results compare favorably with the predictions of a recent neural network model that uses a recurrent architecture to perform optimal cue integration, suggesting that the brain could use a similar computational strategy to integrate sensory signals expressed in distinct frames of reference.