Contextual modulation via low-level vision processing

Gabor wavelets are well established as being useful for modeling neuronal response properties of the primary visual cortex. However, current Gabor models do not account for long-range contextual modulation. This paper introduces a new model which extends a state-of-the-art model of contextual modulation by incorporating long-range convolution at the scale of the visual field. The significance of this new mechanism is that it accounts for perceptual filling-in of occluded receptive fields with purely low-level vision processing.

Fig. 1 displays simulation results of long-range contextual modulation. (Left) panel shows input signal, retinal field with an image of an oriented bar with a gap simulating the occlusion of a receptive field. (Right) panel displays model's simulated output of the response of the pinwheel like structures of primary visual cortex, where it can be observed that the iso-orientation line of the pinwheel associated with the occluded receptive field is activated along the angle of orientation of the input signal.Figure optionsDownload high-quality image (98 K)Download as PowerPoint slideHighlights
► The model of the primary visual cortex presented in this paper, Gabor Energy Transform (GET).
► Accounts for long-range contextual modulation.
► Accounts for certain types of perceptual filling-in.
► Is consistent with predictions made by other state-of-the-art models.