Playing the Simon game: Use of the Simon task for investigating human information processing

A little more than 40 years ago, J. R. Simon and colleagues introduced what is now called the Simon task, which yielded a correspondence effect known as the Simon effect. In this paper, I set Simon's contribution in the context of research on stimulus-response compatibility. The novel contribution of the Simon task is described, along with foundational findings using the task that Simon and colleagues reported. I acknowledge the significance of Simon's (1990) review chapter in generating my own interests in the Simon task and describe four selected lines of research from my lab that have been a result of those interests. The article concludes with a brief tribute to Simon and his contribution to experimental psychology.     

Correspondence effects for objects with opposing left and right protrusions

Choice reactions to a property of an object stimulus are often faster when the location of a graspable part of the object corresponds with the location of a keypress response than when it does not, a phenomenon called the object-based Simon effect. Experiments 1-3 examined this effect for variants of teapot stimuli that were oriented to the left or right. Whether keypress responses were made with fingers within the same hand or between different hands was also manipulated. Experiment 1 showed that, for judgments of stimulus color and upright-inverted orientation, the Simon effect for intact teapots occurred in the direction of the spout location and was larger for within- than between-hand response modes. In Experiments 2 and 3, teapots with the handle or spout removed showed separate contributions of each component to the Simon effect. In Experiment 4, we clarified a discrepancy between our findings of object-based Simon effects and a previously reported absence of effect with color judgments for door-handle stimuli. We obtained an object-based Simon effect with respect to handle position when the bases of the door handles were centered but not when the handles were centered. The findings that object-based Simon effects occur with color judgments and when responses are fingers on the same hand are in closer agreement with a location coding account than with a grasping affordance account.     

Relationships between quality of life and finding benefits in a diagnosis of colorectal cancer

This longitudinal study investigated relations between benefit‐finding domains and outcome measures. Participants were 1,757 individuals diagnosed with colorectal cancer. A written questionnaire and telephone interview were completed at 5‐months (Time 1) and 12‐months post‐diagnosis (Time 2). Exploratory and confirmatory factor analyses revealed three psychometrically sound factors: personal growth, interpersonal growth, and acceptance. Results of regression analyses were conducted and found that Time 1 benefit‐finding domains accounted for significant amounts of variance in Time 1 positive affect and cancer‐related quality of life (both the aggregate score and its social/family, functional, and colorectal cancer‐specific well‐being subscales). Time 1 personal growth also predicted Time 1 psychological distress. After controlling for Time 1 positive affect, personal growth continued to predict Time 2 positive affect. Results delineate the benefit‐finding domains in the context of colorectal cancer and their differential links with outcome measures cross‐sectionally, and longitudinally. These findings have implications for theory building and the measurement of benefit‐finding.     

Improving performance through implementation intentions: Are preexisting response biases replaced?

Commonly, the focus of a planned behavior is to attain some future goal. An alternative to this type of goalfocused, or goal-oriented, strategy is to emphasize the action required to meet the goal rather than to emphasize the goal itself. Previous research has suggested that an action-oriented plan, also known as an implementationintention strategy, increases the chances of successfully reaching an intended future goal with minimal effort by making conscious, deliberate behaviors automatic. We investigated whether, within a Simon task, an implementation-intention strategy eliminates the contribution of preexisting response biases or whether it acts in addition to them. Results of two experiments show that an implementation-intention strategy provides a specific performance benefit that is in addition to, but not in place of, preexisting response biases.     

Age differences in response selection for pure and mixed stimulus-response mappings and tasks

Two experiments examined effects of mixed stimulus-response mappings and tasks for older and younger adults. In Experiment 1, participants performed two-choice spatial reaction tasks with blocks of pure and mixed compatible and incompatible mappings. In Experiment 2, a compatible or incompatible mapping was mixed with a Simon task for which the mapping of stimulus color to location was relevant and stimulus location was irrelevant. In both experiments, older adults showed larger mixing costs than younger adults and larger compatibility effects, with the differences particularly pronounced in Experiment 1 when location mappings were mixed. In mixed conditions, when stimulus location was relevant, older adults benefited more than younger adults from complete repetition of the task and stimulus from the preceding trial. When stimulus location was irrelevant, the benefit of complete repetition did not differ reliably between age groups. The results suggest that the age-related deficit associated with mixing mappings and tasks is primarily due to older adults having more difficulty separating task sets that activate conflicting response codes.     

Task-defined associations are mode specific for selection of relevant dimension but mode independent for selection of location mapping

When compatible and incompatible mappings of a location-relevant task are mixed, or a location-relevant task is mixed with a task for which stimulus location is irrelevant, the benefit of the compatible mapping is eliminated for physical locations and enhanced for location words. Two experiments examined the influence of presenting the location information for the mixed conditions in different stimulus modes (physical location or word). Experiment 1 showed that the effects of mixing location-relevant and location-irrelevant tasks on the spatial compatibility and Simon effects are reduced when the location information is presented in different modes for the two tasks. Experiment 2 showed, in contrast, that the mode distinction had little influence on the effects of mixed compatible and incompatible mappings for location-relevant tasks: The compatibility effect was eliminated for physical locations and enhanced for words, as when there is no mode distinction. Thus, when location is relevant for one task and colour for the other, the task-defined associations of locations to responses are mode specific, but when location is relevant for both tasks, the associations are mode independent.     

Referential coding and attention-shifting accounts of the Simon effect

Summary Stoffer (1991) and Umiltá and Nicoletti (1992) have proposed an attention-shifting account of the Simon effect. However, Hommel (1993) has presented evidence suggesting that the effect can be explained in terms of referential coding, without invoking attentional shifts. Five experiments are reported here, whose primary purpose is to test implications of the referential-coding account. All of the experiments compared conditions in which a noise stimulus was presented in the position opposite the target stimulus with conditions in which it was not. Contrary to the referential-coding account, (a) the basic Simon effect was larger without a fixation point to serve as a referent than with one; (b) the noise stimulus increased the magnitude of the Simon effect when a fixation point was used, but not when there was no fixation point; and (c) the magnitude of the Simon effect obtained in the presence of a noise stimulus was reduced substantially when the noise and the target (and, if present, the fixation point) were in different colors. The results, although counter to predictions of the referential-coding account, can be accommodated by the attention-shifting account if it is assumed that a fixation point provides an anchor that minimizes attention shifts.     

Contextualism: Is the act in context the adequate metaphor for scientific psychology?

According to some, psychology as it has been practiced is based on a world view known as mechanism. Individuals from a number of different areas of psychology, most recently within the behavior-analytic community, have strongly argued that psychology should be based on a different world view, contextualism. They emphasize a variety of characteristics that, in their view, differentiate a contextualistically based psychology from one based on mechanism. We examine these characteristics and find them to be of dubious value for differentiating a contextualistic approach to psychology from others. One proposal of some advocates of contextualism is that contextualistic approaches should develop independently from most of the remainder of psychology, which they regard as mechanistic. This proposal is said to be derived from the metaphilosophy of Pepper (1942). We evaluate this proposal and reject it. We go on to suggest that the mechanis-tic/contextualistic dichotomy is too constraining to realistically describe various approaches to psychology.     

On the advance preparation of discrete finger responses

Most studies that examined the precuing of motor responses have been interpreted as indicating that response specification is a variable-order process. An apparent exception to this conclusion was obtained by Miller (1982) for the preparation of discrete finger responses. Precuing was beneficial only when the precued responses were on the same hand, suggesting that response specification occurs in a fixed order, with hand specified before other aspects of the response. Three experiments examined this discrepant finding for discrete finger responses. Experiment 1 demonstrated that with sufficient time (3 s), all combinations of responses can be equally well prepared. Experiments 2 and 3 showed that the precuing advantage for same-hand responses at shorter precuing intervals is due to strategic and decision factors, not to an ability to prepare these responses more efficiently. Preparation of finger responses, thus, also appears to be variable. This conclusion poses problems for Miller's extension of the precuing procedure to the evaluation of discrete versus continuous models of information processing.