Abstract
In a letter identification task using a four-position array, reaction time (RT) decreased as a negatively accelerated function of the number of targets, both with and without noise letters in nontarget positions. The effect was much greater in the noise condition, in which each redundant target replaced a noise letter. In such situations, the redundant-targets effect should probably be attributed to noise reduction rather than to redundancy. Scaling analysis of the RT distributions indicated that neither noise nor redundancy affects the rate of growth of excitatory strength, but that both affect the time at which growth begins. Excitatory strength grew as a function of the number of redundant targets according to a principle of decreasing gain, with much greater growth in the noise conditions. Further experiments indicated that whether noise is manipulated between or within subjects is important. Unless all stimuli present are reliabl targets, redundancy effects are eliminated or reduced in no-noise conditions.
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References
Biederman, I., &Checkosky, S. F. (1970). Processing redundant information.Journal of Experimental Psychology,83, 486–490.
Eriksen, C. W. (1966). Independence of successive inputs and uncor related error in visual form perception.Journal of Experimental Psychology,72, 26–35.
Eriksen, C. W., &Laphn, J. S. (1965). Internal perceptual system noise and redundancy in simultaneous inputs in form identification.Psychonomic Science,2, 351–352.
Estes, W. K. (1972). Interactions of signal and background variables in visual processing.Perception & Psychophysics,12, 278–286.
Grice, G. R., Canham, L., &Boroughs, J. W. (1984). Combination rule for redundant information in reaction time tasks with divided attention.Perception & Psychophysics,35, 451–463.
Grice, G. R., Canham, L., &Gwynne, J. W. (1984). Absence of a redundant-signals effect in a reaction time task with divided attention.Perception & Psychophysics,36, 565–570.
Holmgren, J. E., Juola, J. F., &Atkinson, R. C. (1974). Response latency in visual search with redundancy in the visual display.Perception & Psychophysics,16, 123–128.
Kinchla, R. A., &Collyer, C. E. (1974). Detecting a target letter in briefly presented arrays: A confidence rating analysis in terms of a weighted additive effects model.Perception & Psychophysics,16, 117–122.
Van Der Heuden, A. H., Schreuder, R., Maris, L., &Neerincx, M. (1984). Some evidence of correlated separate activation in a simple letter detection task.Perception & Psychophysics,36, 577–585.
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Grice, G.R., Gwynne, J.W. Dependence of target redundancy effects on noise conditions and number of targets. Perception & Psychophysics 42, 29–36 (1987). https://doi.org/10.3758/BF03211511
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DOI: https://doi.org/10.3758/BF03211511