No overall right-left prevalence for horizontal

The present study confirmed that there is no overall right—left prevalence effect for Simon tasks, in which stimulus location is irrelevant, when (1) the stimulus and response sets vary along both horizontal and vertical dimensions simultaneously, (2) the stimulus set varies along both dimensions, but the response set varies along only one dimension, and (3) the stimuli and responses vary in one of four possible locations and responses are made by a unimanual joystick movement. In all experiments, Simon effects of similar magnitude were evident for both the horizontal and the vertical dimensions. The findings suggest that the right—left prevalence effect observed with two-dimensional location-relevant tasks is not due to stronger overall automatic activation of horizontal codes but to different translation efficiencies in intentional response selection processes.     

Impaired color word processing at an unattended location: Evidence from a Stroop task combined with inhibition of return

A Stroop task with separate color bar and color word stimuli was combined with an inhibition-of-return procedure to examine whether visual attention modulates color word processing. In Experiment 1, the color bar was presented at the cued location and the color word at the uncued location, or vice versa, with a 100- or 1,050-msec stimulus onset asynchrony (SOA) between cue and Stroop stimuli. In Experiment 2, on Stroop trials, the color bar was presented at a central fixated location and the color word at a cued or uncued location above or below the color bar. In both experiments, with a 100-msec SOA, the Stroop effect was numerically larger when the color word was displayed at the cued location than when it was displayed at the uncued location, but with the 1,050-msec SOA, this relation between Stroop effect magnitude and location was reversed. These results provide evidence that processing of the color word in the Stroop task is modulated by the location to which visual attention is directed.     

Dilution of compatibility effects in Simon-type tasks depends on categorical similarity between distractors and diluters

The presence of a distracting stimulus during performance of the Stroop color-naming task leads to dilution of the Stroop effect. Because the automatic activation of word meaning may interfere with the task-relevant stimulus feature (text color; stimulus-stimulus [S-S] interference) and the response (saying the text color; stimulus-response [S-R] interference), it is unclear which of these types of interference is diluted. We introduce a new dilution paradigm using word- and arrow-based Simon tasks, in which only S-R interference is present. Participants made a left or right response to a central color target. A task-irrelevant location-word (Experiment 1) or arrow (Experiment 2) distractor adjacent to the target produced S-R compatibility effects. An additional neutral word or symbol series (diluter) was sometimes presented on the opposite side of the target from the distractor. The compatibility effect was smaller when the distractor and diluter category domains matched than when they mismatched. This result provides evidence that S-R compatibility effects are susceptible to the presence of diluters that are categorically similar to the distractors.     

Allocation of effort as a function of payoffs for individual tasks in a multitasking environment

SYNWORK1 software allows the examination of how payoffs affect the allocation of effort by people when they perform four different tasks (memory search, arithmetic, visual monitoring, and auditory monitoring). In a previous study (Wang, Proctor, & Pick, 2007), we showed that participants adopted multitasking strategies allocating relative effort appropriate to payoff differences between the arithmetic and memory tasks, but that they exhibited residual effects of prior payoffs when the payoffs were switched. In the present study, we varied the payoff in two different experiments for only one of these tasks, the memory task in Experiment 1 and the arithmetic task in Experiment 2. Doing this allowed consideration of performance for both the task for which payoff changed explicitly and the other cognitive task, for which the payoff difference was implicit (i.e., relative to the explicit payoff that was manipulated). Although participants adjusted performance on the task for which the payoff explicitly varied, the payoff manipulation had less effect than did the explicit payoff manipulations for both tasks used previously. Also, the change in effort on a task resulting from explicitly increasing its payoff was less than that from decreasing the payoff. SYNWORK1 is a good environment for studying multitasking, but has several limitations that need to be addressed to provide a synthetic work environment that allows investigation of a wider range of theoretically relevant issues.     

Influence of color word availability on the Stroop color-naming effect

Three experiments tested whether the Stroop color-naming effect is a consequence of word recognition's being automatic or of the color word's capturing visual attention. In Experiment 1, a color bar was presented at fixation as the color carrier, with color and neutral words presented in locations above or below the color bar; Experiment 2 was similar, except that the color carrier could occur in one of the peripheral locations and the color word at fixation. The Stroop effect increased as display duration increased, and the Stroop dilution effect (a reduced Stroop effect when a neutral word is also present) was an approximately constant proportion of the Stroop effect at all display durations, regardless of whether the color bar or color word was at fixation. In Experiment 3, the interval between the onsets of the to-be-named color and the color word was manipulated. The Stroop effect decreased with increasing delay of the color word onset, but the absolute amount of Stroop dilution produced by the neutral word increased. This study's results imply that an attention shift from the color carrier to the color word is an important factor modulating the size of the Stroop effect.     

Couple resilience and life wellbeing in firefighters

The validity of the Couple Resilience Inventory was tested using 102 married or cohabiting firefighters. This instrument measures types of relationship behavior that often occur during stressful life events and that are expected to be associated with an ability to cope with employment in a stressful occupation. It includes scales measuring two nearly orthogonal dimensions, with one dimension pertaining to positive behavior and the other to negative. Firefighters completed an online questionnaire that included the Couple Resilience Inventory and measures of relationship satisfaction, exposure to traumatic events, and life wellbeing. In line with hypotheses, scales measuring positive and negative couple resilience were nearly orthogonal to each other, and distinct from a measure of relationship satisfaction, but both scales correlated positively with exposure to traumatic events, and both correlated in opposite directions with relationship satisfaction and life wellbeing. Results were consistent with the theoretical model and they supported instrument validity.     

Polarity correspondence: A general principle for performance of speeded binary classification tasks

Differences in performance with various stimulus-response mappings are among the most prevalent findings for binary choice reaction tasks. The authors show that perceptual or conceptual similarity is not necessary to obtain mapping effects; a type of structural similarity is sufficient. Specifically, stimulus and response alternatives are coded as positive and negative polarity along several dimensions, and polarity correspondence is sufficient to produce mapping effects. The authors make the case for this polarity correspondence principle using the literature on word-picture verification and then provide evidence that polarity correspondence is a determinant of mapping effects in orthogonal stimulus-response compatibility, numerical judgment, and implicit association tasks. The authors conclude by discussing implications of this principle for interpretation of results from binary choice tasks and future model development.     

Effects of precuing horizontal and vertical dimensions on right—left prevalence

When stimuli and responses can be coded along horizontal and vertical dimensions simultaneously, a right-left prevalence effect is often obtained for which the advantage for a compatible mapping is larger on the horizontal dimension than on the vertical dimension. The present study investigated the role of preparatory processes in this right-left prevalence effect using a method in which the relevant dimension was cued at short and long intervals prior to presentation of the target stimulus. In three experiments, the right-left prevalence effect did not vary significantly in magnitude as a function of cue-target interval, suggesting that the effect is due primarily to relative salience of the horizontal and vertical codes, as determined by the task structure, and not to a greater ease of attending to the horizontal dimension.     

Display-control arrangement correspondence and logical recoding in the Hedge and Marsh reversal of the Simon effect

When left and right keypresses are made to stimuli in left and right locations, and stimulus location is irrelevant to the task, responses are typically faster when stimulus location corresponds with response location than when it does not (the Simon effect). This effect reverses when the relevant stimulus-response mapping is incompatible, with responses being slower when stimulus and response locations correspond (the Hedge and Marsh reversal). Simon et al. (Acta Psychol. 47 (1981) 63) reported an exception to the Hedge and Marsh reversal for a situation in which the relevant stimulus dimension was the color of a centered visual stimulus and the irrelevant location information was left or right tone location. In contrast, similar experiments have found a reversal of the Simon effect for tone location when relevant visual locations were mapped incompatibly to responses. We conducted four experiments to investigate this discrepancy. Both results were replicated. With an incompatible mapping, irrelevant tone location showed a small reverse Simon effect when the relevant visual dimension was physical location but not when the color of a centered stimulus or the direction in which an arrow pointed conveyed the visual location information. The reversal occurred in a more standard Hedge and Marsh task in which the irrelevant dimension was location of the colored stimulus, but only when the response keys were visibly labeled. Several of the results suggest that display-control arrangement correspondence is the primary cause of the Hedge and Marsh reversal, with logical recoding playing only a secondary role.     

Intrahemispherical activation,visuomotor transmission,and the Simon effect: comment on Wascher et al. (2001)

On the basis of 3 experiments E. Wascher, U. Schatz, T. Kuder, and R. Verleger (2001) concluded, "The variety of tasks subsumed under the term Simon effect turned out to be heterogeneous" (p. 749). This comment critically evaluates the validity of their conclusion by considering their hypotheses methodology, specific conclusions, and proposed broader implications. Although the Simon effect is a behavioral phenomenon, E. Wascher et al. relied heavily on physiology in hypothesis generation, methodology, and interpretation of results. Moreover, methodological differences from most previous studies, combined with limited statistical support, nonreplication of previously reported behavioral phenomena inconsistencies in results across experiments, and evidence against a contribution of intrahemispherical activation by visuomotor pathways, strongly suggest that their conclusion should be viewed with caution.