From coarse to fine? Spatial and temporal dynamics of cortical face processing.
Primary vision segregates information along 2 main dimensions: orientation and spatial frequency (SF). An important question is how this primary visual information is integrated to support high-level representations. It is generally assumed that the information carried by different SF is combined following a coarse-to-fine sequence. We directly addressed this assumption by investigating how the network of face-preferring cortical regions processes distinct SF over time. Face stimuli were flashed during 75, 150, or 300 ms and masked. They were filtered to preserve low SF (LSF), middle SF (MSF), or high SF (HSF). Most face-preferring regions robustly responded to coarse LSF, face information in early stages of visual processing (i.e., until 75 ms of exposure duration). LSF processing decayed as a function of exposure duration (mostly until 150 ms). In contrast, the processing of fine HSF, face information became more robust over time in the bilateral fusiform face regions and in the right occipital face area. The present evidence suggests the coarse-to-fine strategy as a plausible modus operandi in high-level visual cortex.
Goffaux
Valerie
V
Educational Measurement and Applied Cognitive Science Unit and Faculté des Lettres, des Sciences Humaines, des Arts et des Sciences de l'Education, University of Luxembourg, L-7210 Walferdange, Luxembourg. valerie.goffaux@maastrichtuniversity.nl
Peters
Judith
J
Haubrechts
Julie
J
Schiltz
Christine
C
Jansma
Bernadette
B
Goebel
Rainer
R
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply / Q000502:physiology*; D005145:Face; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010100:Oxygen / Q000097:blood; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011601:Psychophysics; D013028:Space Perception / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult
D010100:Oxygen