title: Early and late components of visual categorization: an event-related potential study.
abstract: We examined the characteristics of early and late components of event-related potentials (ERPs) accompanying the visual categorization of natural scenes. In the first experiment, ERPs were recorded in an animal-non-animal categorization task (CT), whereas the second experiment included a spatial frequency discrimination task (DT). In the CT, there were more negative potentials for non-animals in the time windows of 150-250 ms (N1) and 350-500 ms (N2), and a more positive potential for animals in the time window of 250-350 ms (P2). In the DT, spatial frequency gratings evoked only a short-duration difference N1 at the frontal sites. Our results suggest that N1 may be related to higher-level categorization processes.
authors.affiliation: Department of Physiology, Albert Szent-Györgyi Medical University, POB 1192, H-6720, Szeged, Hungary. aantal@phys.szote.u-szeged.hu
authors.forename: A
authors.initials: A
authors.lastname: Antal
authors.forename: S
authors.initials: S
authors.lastname: Kéri
authors.forename: G
authors.initials: G
authors.lastname: Kovács
authors.forename: Z
authors.initials: Z
authors.lastname: Janka
authors.forename: G
authors.initials: G
authors.lastname: Benedek
mesh_terms: D000328:Adult; D004193:Discrimination Learning / Q000502:physiology; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D012660:Semantics