Abstract
An important discovery of the last two decades is that receptive fields in early visual cortex provide an efficient basis for generating images that have the statistical structure of natural scenes. This discovery has lent impetus to the theory that receptive fields in early visual cortex can function not only as passive filters of retinal input, but as mechanisms for generating accurate representations of the visual environment that are independent of retinal input. A number of theoretical studies argued that such internal visual representations could play an important functional role in vision by supporting probabilistic inference. In this talk, we will explore the idea of receptive fields as generators of internal representations by examining the role that receptive fields play in generating mental images. Mental images are the canonical form of internal visual representation: they are independent of retinal input and appear to be essential for many forms of inference. We present evidence from fMRI studies that voxel-wise receptive field models of the tuning to retinotopic location, orientation, and spatial frequency can account for much of the BOLD response in early visual cortex to imagining previously memorized works of art. We will discuss the implications of this finding for the structure of functional feedback projections to early visual cortex, and for the development of brain-machine interfaces that are driven by mental imagery.
Meeting abstract presented at VSS 2014