title: Shared representations for working memory and mental imagery in early visual cortex.
abstract: Early visual areas contain specific information about visual items maintained in working memory, suggesting a role for early visual cortex in more complex cognitive functions [1-4]. It is an open question, however, whether these areas also underlie the ability to internally generate images de novo (i.e., mental imagery). Research on mental imagery has to this point focused mostly on whether mental images activate early sensory areas, with mixed results [5-7]. Recent studies suggest that multivariate pattern analysis of neural activity patterns in visual regions can reveal content-specific representations during cognitive processes, even though overall activation levels are low [1-4]. Here, we used this approach [8, 9] to study item-specific activity patterns in early visual areas (V1-V3) when these items are internally generated. We could reliably decode stimulus identity from neural activity patterns in early visual cortex during both working memory and mental imagery. Crucially, these activity patterns resembled those evoked by bottom-up visual stimulation, suggesting that mental images are indeed "perception-like" in nature. These findings suggest that the visual cortex serves as a dynamic "blackboard" [10, 11] that is used during both bottom-up stimulus processing and top-down internal generation of mental content.
authors.affiliation: Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Kapittelweg 29, 6525 EN Nijmegen, the Netherlands.
authors.forename: Anke Marit
authors.initials: AM
authors.lastname: Albers
authors.forename: Peter
authors.initials: P
authors.lastname: Kok
authors.forename: Ivan
authors.initials: I
authors.lastname: Toni
authors.forename: H Chris
authors.initials: HC
authors.lastname: Dijkerman
authors.forename: Floris P
authors.initials: FP
authors.lastname: de Lange
mesh_terms: D007839:Functional Laterality; D006801:Humans; D007092:Imagination / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008570:Memory, Short-Term / Q000502:physiology*; D015999:Multivariate Analysis; D033281:Nontherapeutic Human Experimentation; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology