title: Connectivity Reveals Sources of Predictive Coding Signals in Early Visual Cortex During Processing of Visual Optic Flow.
abstract: Superimposed on the visual feed-forward pathway, feedback connections convey higher level information to cortical areas lower in the hierarchy. A prominent framework for these connections is the theory of predictive coding where high-level areas send stimulus interpretations to lower level areas that compare them with sensory input. Along these lines, a growing body of neuroimaging studies shows that predictable stimuli lead to reduced blood oxygen level-dependent (BOLD) responses compared with matched nonpredictable counterparts, especially in early visual cortex (EVC) including areas V1-V3. The sources of these modulatory feedback signals are largely unknown. Here, we re-examined the robust finding of relative BOLD suppression in EVC evident during processing of coherent compared with random motion. Using functional connectivity analysis, we show an optic flow-dependent increase of functional connectivity between BOLD suppressed EVC and a network of visual motion areas including MST, V3A, V6, the cingulate sulcus visual area (CSv), and precuneus (Pc). Connectivity decreased between EVC and 2 areas known to encode heading direction: entorhinal cortex (EC) and retrosplenial cortex (RSC). Our results provide first evidence that BOLD suppression in EVC for predictable stimuli is indeed mediated by specific high-level areas, in accord with the theory of predictive coding.
authors.affiliation: Vision and Cognition Lab, Centre for Integrative Neuroscience and.|Department of Psychology, University of Tübingen, Tübingen 72076, Germany.|Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schindler
authors.affiliation: Vision and Cognition Lab, Centre for Integrative Neuroscience and.|Department of Psychology, University of Tübingen, Tübingen 72076, Germany.|Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Bartels
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D001931:Brain Mapping; D002560:Cerebrovascular Circulation / Q000502:physiology*; D017352:Echo-Planar Imaging; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D057849:Optic Flow / Q000502:physiology*; D010775:Photic Stimulation; D011601:Psychophysics; D014793:Visual Cortex / Q000000981:diagnostic imaging / Q000502:physiology; D014795:Visual Pathways / Q000000981:diagnostic imaging / Q000502:physiology*; D055815:Young Adult
keywords: MST; V1; connectivity; fMRI; feedback; predictive coding