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| Macaluso, E., Frith, C., Driver, J. Modulation of human visual cortex by crossmodal spatial attention Science 2000 (289):1206-1208 [html] |
| A sudden touch on one hand can improve vision near that hand, revealing crossmodal links in spatial attention. It is often assumed that such links involve only multimodal neural structures, but unimodal brain areas may also be affected. We tested the effect of simultaneous visuo-tactile stimulation on the activity of the human visual cortex. Tactile stimulation enhanced activity in the visual cortex, but only when it was on the same side as a visual target. Analysis of effective connectivity between brain areas suggests that touch influences unimodal visual cortex via back-projections from multimodal parietal areas. This provides a neural explanation for crossmodal links in spatial attention. |
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| Tenenbaum, J.B., de Silva, V., Langford, J.C. Nonlinear Dimensionality Reduction by Locally Linear Embedding Science 2000 (290):2323-2326 [pdf] |
| Many areas of science depend on exploratory data analysis and visualization. The need to analyze large amounts of multivariate data raises the fundamental problem of dimensionality reduction: how to discover compact representations of high-dimensional data. Here, we introduce locally linear embedding (LLE), an unsupervised learning algorithm that computes low-dimensional, neighborhood- preserving embeddings of high-dimensional inputs. Unlike clustering methods for local dimensionality reduction, LLE maps its inputs into a single global coordinate system of lower dimensionality, and its optimizations do not involve local minima. By exploiting the local symmetries of linear reconstructions, LLE is able to learn the global structure of nonlinear manifolds, such as those generated by images of faces or documents of text. |
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| Schlaer, R. Shift in binocular disparity causes compensatory change in the cortical structure of kittens Science 1971 (173):638-641 |
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| Hirsch, H., Spinelli, D. Visual experience modifies distribution of horizontally and vertically oriented receptive fields in cats Science 1970 (168):869-871 |
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