Mixing compatible and incompatible mappings: Elimination, reduction, and enhancement of spatial compatibility effects

Abstract

In two-choice tasks, the compatible mapping of left stimulus to left response and right stimulus to right response typically yields better performance than does the incompatible mapping. Nonetheless, when compatible and incompatible mappings are mixed within a block of trials, the spatial compatibility effect is eliminated. Two experiments evaluated whether the elimination of compatibility effects by mixing compatible and incompatible mappings is a general or specific phenomenon. Left-right physical locations, arrow directions, and location words were mapped to keypress responses in Experiment 1 and vocal responses in Experiment 2. With keypresses, mixing compatible and incompatible mappings eliminated the compatibility effect for physical locations and arrow directions, but enhanced it for words. With vocal responses, mixing significantly reduced the compatibility effect only for words. Overall, the mixing effects suggest that elimination or reduction of compatibility effects occurs primarily when the stimulus-response sets have both conceptual and perceptual similarity. This elimination may be due to suppression of a direct response-selection route, but to account for the full pattern of mixing effects it is also necessary to consider changes in an indirect response-selection route and the temporal activation properties of different stimulus-response sets.

Stimulus and response representations underlying orthogonal stimulus-response compatibility effects

“…However, the pattern of diverging functions obtained from the experiments with vertical stimuli and horizontal responses does not provide strong evidence indicating a switch from symmetric to asymmetric codes. This diverging pattern is also evident in experiments for which the stimulus and response sets are parallel (Roswarski & Proctor, 1996, Experiment 4;Vu & Proctor, 2002a), and the slope of the RT quantile plot is sensitive to factors other than the time course for two different processes (see, e.g., Vu & Proctor, 2002a;Zhang & Kornblum, 1997). Umiltà (1991) pointed out that the up-right/down-left advantage was larger with vocal responses than with manual responses in Weeks and Proctor's (1990) study.…”

Strategies of flanker coprocessing in single and dual tasks.

“…Mixing of trial types has often been used to investigate strategic versus nonstrategic components of behavior, as, for instance, in studies of the Simon effect (e.g., Marble & Proctor, 2000;Proctor & Vu, 2002;Proctor et al, 2003;Vu & Proctor, 2004). With mixed trial types, however, participants have to be informed about what to do on the current trial.…”

How task errors affect subsequent behavior: Evidence from distributional analyses of task-switching effects

“…The dual-process idea can be found in different but related domains (see, e.g., Hommel, 1998;Kornblum et al, 1990;Logan, 1988;Schneider & Shiffrin, 1977;Steinhauser & Hübner, 2005) and was used as a conceptual framework by Ridderinkhof (2002). Most importantly, dual-process models have been used to account for differential effects in the fast and slow tails of the RT distribution (e.g., De Jong, Liang, & Lauber, 1994;Gratton, Coles, Sirevaag, Eriksen, & Donchin, 1988;Vu & Proctor, 2004); slow responses are assumed to reflect the controlled process, whereas fast responses are thought to reflect the automatic process.…”