Cognition. The manifold ways of perception.

One of the great puzzles of visual perception is how an image that is in perpetual flux can still be seen by the observer as the same object. In an informative Perspective, Seung and Lee explain the mathematical intricacies of two new algorithms for modeling the variability of perceptual stimuli and other types of high-dimensional data (Tenenbaum et al., and Roweis and Saul).