title: Spatial frequency processing in scene-selective cortical regions.
abstract: Visual analysis begins with the parallel extraction of different attributes at different spatial frequencies. Low spatial frequencies (LSF) convey coarse information and are characterized by high luminance contrast, while high spatial frequencies (HSF) convey fine details and are characterized by low luminance contrast. In the present fMRI study, we examined how scene-selective regions-the parahippocampal place area (PPA), the retrosplenial cortex (RSC) and the occipital place area (OPA)-responded to spatial frequencies when contrast was either equalized or not equalized across spatial frequencies. Participants performed a categorization task on LSF, HSF and non-filtered scenes belonging to two different categories (indoors and outdoors). We either left contrast across scenes untouched, or equalized it using a root-mean-square contrast normalization. We found that when contrast remained unmodified, LSF and NF scenes elicited greater activation than HSF scenes in the PPA. However, when contrast was equalized across spatial frequencies, the PPA was selective to HFS. This suggests that PPA activity relies on an interaction between spatial frequency and contrast in scenes. In the RSC, LSF and NF elicited greater response than HSF scenes when contrast was not modified, while no effect of spatial frequencies appeared when contrast was equalized across filtered scenes, suggesting that the RSC is sensitive to high-contrast information. Finally, we observed selective activation of the OPA in response to HSF, irrespective of contrast manipulation. These results provide new insights into how scene-selective areas operate during scene processing.
authors.affiliation: Univ. Grenoble Alpes, LPNC, F-38040 Grenoble, France; CNRS, LPNC UMR 5105, F-38040 Grenoble, France. Electronic address: louise.kauffmann@upmf-grenoble.fr.
authors.forename: Louise
authors.initials: L
authors.lastname: Kauffmann
authors.affiliation: Univ. Grenoble Alpes, LPNC, F-38040 Grenoble, France; CNRS, LPNC UMR 5105, F-38040 Grenoble, France; INSERM U836, GIN, F-38706 Grenoble, France.
authors.forename: Stephen
authors.initials: S
authors.lastname: Ramanoël
authors.affiliation: Univ. Grenoble Alpes, GIPSA-lab, F-38402 Grenoble, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Guyader
authors.affiliation: Univ. Grenoble Alpes, LPNC, F-38040 Grenoble, France; CNRS, LPNC UMR 5105, F-38040 Grenoble, France.
authors.forename: Alan
authors.initials: A
authors.lastname: Chauvin
authors.affiliation: Univ. Grenoble Alpes, LPNC, F-38040 Grenoble, France; CNRS, LPNC UMR 5105, F-38040 Grenoble, France.
authors.forename: Carole
authors.initials: C
authors.lastname: Peyrin
mesh_terms: D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology*; D004777:Environment; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009778:Occipital Lobe / Q000502:physiology; D020534:Parahippocampal Gyrus / Q000502:physiology*; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D013028:Space Perception / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology; D055815:Young Adult
keywords: Occipital place area; Parahippocampal place area; Retrosplenial cortex; Root mean square contrast; Spatial frequencies