Visual imagery and visual representation

Among many controversies in visual neuroscience is whether visual imagery of objects, scenes and living beings is based upon contributions of the early visual areas or depends on hierarchical higher visual areas only, and whether the cortical areas subserving visual imagery are identical to those underlying visual perception. These questions are important for furthering our understanding of vision, since areas active in visual imagery might tell us how the visual cortex represents objects, scenes and living beings. Here, P.E. Roland and B. Gulyás present their hypothesis, based on experimental evidence in man and primates, that the visual areas subserving visual imagery are parieto-occipital and temporo-occipital visual association areas, and that these areas form only a subset of the visual areas engaged in perception. This hypothesis is consistent with the view that objects, scenes and living beings are represented, stored and re-evoked outside the domain of the primary visual cortex and its immediate neighbours.