Channel surfing in the visual brain

• Published in: Trends in cognitive sciences Vol. 10; no. 12; pp. 538 - 545
• Main Authors: Sowden, Paul T., Schyns, Philippe G.
• Format: Journal Article
• Language: English
• Published: London Elsevier Ltd 01-12-2006; Elsevier
• Subjects: Biological and medical sciences; Brain - physiology; Discrimination Learning - physiology; Fundamental and applied biological sciences. Psychology; Humans; Models, Psychological; Nerve Net - physiology; Pattern Recognition, Visual - physiology; Perception; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Psychophysiology - methods; Space Perception - physiology; Vision; Human; Spatial frequency; Acquisition process; Vision; Central nervous system; Perception; Cognition; Review; Perceptive learning; Categorization; Encephalon
• ISSN: 1364-6613; 1879-307X
• DOI: 10.1016/j.tics.2006.10.007

Vision provides us with an ever-changing neural representation of the world from which we must extract stable object categorizations. We argue that visual analysis involves a fundamental interaction between the observer's top-down categorization goals and the incoming stimulation. Specifically, we discuss the information available for categorization from an analysis of different spatial scales by a bank of flexible, interacting spatial-frequency (SF) channels. We contend that the activity of these channels is not determined simply bottom-up by the stimulus. Instead, we argue that, following perceptual learning a specification of the diagnostic, object-based, SF information dynamically influences the top-down processing of retina-based SF information by these channels. Our analysis of SF processing provides a case study that emphasizes the continuity between higher-level cognition and lower-level perception.