Santos, L. M.du Buf, J. M. H.2015-11-042015-11-0420023-540-00174-30302-9743AUT: DUB00865;http://hdl.handle.net/10400.1/6960Area VI and higher areas in the visual cortex contain many feature extraction engines that serve to build a symbolic image representation. In this paper we present models of cells that complement a multiscale line and edge extraction. After reviewing a frontend that comprises Gabor filters (simple cells), bar and grating cells, we introduce a bar cell grouping for completing occluded curvilinear structures (snakes), as well as a grating cell grouping for coding periodic textures with different complexities.engPerceptual groupingCortical cellsjournal article