Visual and mental exploration of visuo-spatial configurations: Behavioral and neuroimaging approaches

Do mental imagery and perception involve common processing mechanisms? Imag ery researchers haw devoted a great deal of effort to establishing the func tional and structural similarities between images and perceptual events. Re cent studies have focused on the comparison of images that are reconstructi ons of previous perceptual experience and images constructed from verbal de scriptions. This article reports the findings of a research program based o n the mental scanning paradigm, they reveal the similarities and difference s between the two kinds of mental images. Neuroimaging studies have also pr ovided evidence that the parietooccipital cortex is involved in the process ing of visual images, whether they are based on perceptual experience or co nstructed from linguistic inputs. However, the PET studies conducted by our research groups provide no evidence that the primary visual cortex is enga ged in the generation of visual images. As there is contradictory evidence about this, further research is needed to clarify the role of the early vis ual areas in mental visual imagery.