| Abstract: | How the brain processes information is partly determined by the characteristics of the input. To examine whether the 2 cerebral hemispheres are equally affected by manipulations of quality of incoming information, 3 experiments using M. I. Posner and R. F. Mitchell's (1967) paradigm (matching pairs of letters of same or different case or name) were conducted under 8 viewing conditions, consisting of manipulations of exposure duration, retinal eccentricity, and stimulus size. The same procedure but different designs were used in the 3 studies: a between-S design in Exp I; a within-S design with viewing conditions blocked in Exp II; and a within-S design with viewing conditions mixed in Exp III. In all experiments, which used 88 18–30 yr old right-handed Ss, exposure duration and retinal eccentricity each interacted with visual fields, whereas the interaction of letter size and visual field was significant only in Exp II. Results are interpreted with respect to the properties of the visual system and its capacity to extract information in terms of the spatial-frequency spectral components of a stimulus. Methodological implications are discussed. (French abstract) (2? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
