Visual Population Codes ─ Toward a Common Multivariate Framework for Cell Recording and Functional Imaging

Vision is a massively parallel computational process, in which the retinal image istransformed over a sequence of stages so as to emphasize behaviorally relevant information (such asobject category and identity) and deemphasize other information (such as viewpoint and lighting).The processes behind vision operate by concurrent computation and message passing among neuronswithin a visual area and between different areas. The theoretical concept of "populationcode" encapsulates the idea that visual content is represented at each stage by the pattern ofactivity across the local population of neurons. Understanding visual population codes ultimatelyrequires multichannel measurement and multivariate analysis of activity patterns. Over the pastdecade, the multivariate approach has gained significant momentum in vision research. Functionalimaging and cell recording measure brain activity in fundamentally different ways, but they now usesimilar theoretical concepts and mathematical tools in their modeling and analyses. With a focus onthe ventral processing stream thought to underlie object recognition, this book presents recentadvances in our understanding of visual population codes, novel multivariate pattern-informationanalysis techniques, and the beginnings of a unified perspective for cell recording and functionalimaging. It serves as an introduction, overview, and reference for scientists and students acrossdisciplines who are interested in human and primate vision and, more generally, in understanding howthe brain represents and processes information.

Nikolaus Kriegeskorte is Principal Investigator at the Medical Research Council Cognition and Brain Sciences Unit in Cambridge, UK. Gabriel Kreiman is Assistant Professor in the Department of Ophthalmology at Children's Hospital Boston, Harvard Medical School.