Conceptual and perceptual components of interletter inhibition

In 3 experiments with 36 undergraduates the effects of target-noise similarity on the ability to discriminate between 2 target letters was investigated. In one paradigm, Ss had to report which of 2 target letters, (e.g., A or E) had appeared in a location specified by a poststimulus cue. In the other, Ss simply had to indicate whether either target was presented, without regard to location. Results from both paradigms indicate that performance was poorer when the noise letter was the same as the target letter (e.g., AA) than when it is the other target (e.g., AE) or a nontarget (e.g., AK). Performance was also low when the noise letter shared only the same name as the target (e.g., Aa). This indicates that interletter interference effects cannot be entirely explained in terms of inhibition between visual features. Results are discussed in terms of a hypothesis of "cognitive masking" and the relations between findings on inhibition due to stimulus repetition and findings of facilitation due to stimulus repetition. (34 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved).