The visual system is able to complete portions of visual scene that lack structure by incorporating contextual information about color, texture, and contours from the surrounding area. We previously demonstrated (SFN, 2003) that many neurons in primary visual cortex (V1) can rapidly interpolate the structure in an image occluded by a mask centered on their receptive fields. We used a subspace reverse correlation technique to estimate the linear kernels of simple cortical cells in two conditions: 1) a full-view condition consisting of a rapid sequence of high-contrast sine wave gratings drawn from a Hartley (sinusoidal gratings) basis set, and 2) a masked condition, which consisted of the same grating stimuli and a uniform grey mask centered on the receptive field and scaled to occlude nearly half of its area. Here we extend these observations by studying how image completion depends on the spatial extent and location of the mask. We used multi-electrode arrays to simultaneously record from a population of ...