Author:

Keywords:

Adult, Analysis of Variance, Brain Mapping, Cerebral Cortex, Face, Female, Functional Laterality, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Male, Oxygen, Pattern Recognition, Visual, Photic Stimulation, Psychophysics, Space Perception, Time Factors, Young Adult, Science & Technology, Life Sciences & Biomedicine, Neurosciences, Neurosciences & Neurology, coarse-to-fine, exposure duration, face perception, fMRI, spatial frequency, HUMAN OCCIPITOTEMPORAL CORTEX, TOP-DOWN FACILITATION, NATURAL IMAGES, VISUAL-CORTEX, INFEROTEMPORAL CORTEX, RESPONSE PROPERTIES, OBJECT RECOGNITION, RECEPTIVE-FIELDS, INVERTED FACES, FREQUENCY, 1109 Neurosciences, 1701 Psychology, 1702 Cognitive Sciences, Experimental Psychology, 3209 Neurosciences, 5202 Biological psychology, 5204 Cognitive and computational psychology

Abstract:

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.