Does irrelevant stimulus location affect response selection?

Reaction time (RT) is shorter when the irrelevant location of the stimulus corresponds to the relevant location of the response: When a subject is to perform a left or right keypress according to the colour of a stimulus delivered either to the left or to the right of a fixation, RT is typically shorter when the location of the stimulus corresponds to the location of the response (e.g., left stimulus/left response) than when it does not (e.g., left stimulus/right response). Umiltà and Nicoletti (1990) have suggested that this effect, known as the ?Simon effect' in the literature, occurred at the response selection stage, a stage whose duration depends on the effectors used to perform the task. In the present study, this effect and that of the finger response repertoire (within- versus between-hand composition) were found to be additive, which does not support the response selection hypothesis of the Simon effect.     

Control over location-based response activation in the Simon task: Behavioral and electrophysiological evidence.

In 4 Simon experiments the authors examined control over 2 routes of sensorimotor processing: response priming in the unconditional route and response selection via the conditional route. The Simon effect diminished as the frequency of noncorresponding trials increased. Location-based response priming was observed only when the stimulus followed a corresponding event but not after a noncorresponding trial. Therefore, the unconditional route appears to be suppressed whenever the task context indicates priming as potentially disadvantageous. Moreover, the task-irrelevant stimulus location was used for response selection as a function of correspondence probability. Although exact repetitions of stimulus-response sequences caused a marked speed-up of responses, this 3rd mechanism is independent of unconditional route suppression and frequency-based adjustments in the conditional route. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention is required for acquisition but not expression of new response biases.

Throughout a lifetime of interaction with the physical environment, people develop a strong bias to respond on the same side as the location of a target object, even when its location is irrelevant to the task at hand. Recent research has shown that this compatibility bias can be overridden with relatively brief but focused training. To better understand how such training affects preexisting response biases, we investigated whether attention is required to acquire and express a new bias to respond on the opposite side, thus creating an incompatibility bias. Participants practiced making responses on the opposite side from left and right tones and then made responses based on the frequencies (high or low) of the same tones. As in previous research, practice with a spatially incompatible mapping eliminated the compatible bias in the Simon task. The addition of an attention load (continuous secondary tracking task) during practice prevented learning the new response bias. However, once the new bias was learned, it overrode the compatibility bias regardless of available attentional resources. We suggest that not only can a quickly learned response bias overwhelm preexisting biases that are acquired over years of experience but that recently learned and older, preexisting biases are similarly affected by attention load. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The absence of a gender congruency effect in romance languages: A matter of stimulus onset asynchrony?

Using the picture-word interference paradigm, H. Schriefers and E. Teruel (2000) found that in German the grammatical gender of the distractor word affects the production of phrases composed of article+picture name: Latencies were longer for picture-word pairs of different genders. However, the effect was found only at positive stimulus onset asynchronies (SOAs; i.e., when pictures were presented 75 or 150 ms earlier than word distractors). This gender congruency effect is not obtained in Romance languages. The present article examines whether in these languages, as in German, the effect appears at positive SOAs. No effect was observed in Italian and Spanish at positive SOAs. An account is proposed to explain why the gender congruency effect is obtained in Germanic (Dutch and German) but not in Romance languages. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Validity and boundary conditions of automatic response activation in the Simon task.

Three experiments were conducted to determine whether spatial stimulus-response compatibility effects are caused by automatic response activation by stimulus properties or by interference between codes during translation of stimulus into response coordinates. The main evidence against activation has been that in a Simon task with hands crossed, responses are faster at the response location ipsilateral to the stimulus though manipulated by the hand contralateral to the stimulus. The experiments were conducted with hands in standard and in crossed positions and electroencephalogram measures showed coactivation of the motor cortex induced by stimulus position primarily during standard hand positions with visual stimuli. Only in this condition did the Simon effect decay with longer response times. The visual Simon effect appeared to be due to specific mechanisms of visuomotor information transmission that are not responsible for the effects obtained with crossed hands or auditory stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The impact of stimulus and response variability on S-R correspondence effects.

Six experiments investigated how variability on irrelevant stimulus dimensions and variability on response dimensions contribute to spatial and nonspatial stimulus-response (S-R) correspondence effects. Experiments 1-3 showed that, when stimuli varied in location and number, S-R correspondence effects for location or numerosity occurred when responses varied on these dimensions but not when responses were invariant on these dimensions. These results are consistent with the response-discrimination account, according to which S-R correspondence effects should only arise for a dimension that is used for discriminating between responses in working memory. Experiments 4-6 showed that, when responses varied in location and number, both invariant and variable stimulus number produced correspondence effects in S-R numerosity. In summary, the present results indicate that the usefulness of a particular dimension for response discrimination can be sufficient for producing S-R correspondence effects, whereas variability of a stimulus dimension is not sufficient for producing such effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dynamic Aspects of Stimulus-Response Correspondence: Evidence for Two Mechanisms Involved in the Simon Effect.

It has been recently proposed that the time course of the Simon effect may vary across tasks, which might reflect different types of stimulus-response (S-R) transmissions (E. Wascher, U. Schatz, T. Kuder, & R. Verleger, 2001). The authors tested this notion in 4 experiments by comparing Simon effects evoked by horizontal and vertical S-R arrangements. The temporal properties of the effect, as well as lateralized readiness potential-difference waves, indicated a fast and transient influence of the horizontal, but a slow and sustained influence of the vertical spatial stimulus feature on performance. Additional evidence for this temporal dissociation was obtained in experiments that induced a shortening or lengthening of the mean response time. Thus, the data strongly indicate that there are 2 temporally dissociable mechanisms involved in generating the Simon effect for horizontal and vertical S-R relations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The influence of temporal selection on spatial selection and distractor interference: An attentional blink study.

Both spatial and temporal selection require focused attention. The authors examine how temporal attention affects spatial selection. In a dual-task rapid serial visual presentation paradigm, temporal selection of a target (T1) impairs processing of a second target (T2) that follows T1 within 500 ms. This process is the attentional blink (AB). To test the effects of withdrawing temporal attention, the authors measured concurrent distractor interference on T2 when the distractors were presented during and outside of the AB. Perceptual interference was manipulated by the similarity in color between T2 and concurrent distractors, and response interference was manipulated by the flanker congruency task. Results showed that perceptual interference was larger during the AB. Response interference also increased during the AB, but only when perceptual interference was high. The authors conclude that temporal selection and spatial selection rely on a common attentional process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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; see record 2001-06699-017) 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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Temporal stimulus–response compatibility.

The study of element-level stimulus–response compatibility (SRC) has predominantly focused on spatial and symbolic relationships and has involved measures of response time and (dichotomous) error rate. This article explores a new form of SRC that is observed when duration is the relevant feature of both the stimulus and the response, using a more extensive analysis of performance accuracy and variability. The results indicate that element-level SRC generalizes to situations involving time as the relevant dimension of stimuli and responses. Evidence of this was found in all of the extracted measures of performance; however, temporal SRC was shown to have independent effects on when and how accurately a response was made. Implications for SRC research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Coding controlled and triggered cursor movements as action effects: Influences on the auditory Simon effect for wheel-rotation responses.

Four experiments investigated influences of irrelevant action effects on response selection in Simon tasks for which tone pitch was relevant and location irrelevant, and responses were clockwise- counterclockwise wheel rotations. When the wheel controlled left-right movement of a cursor in a direction opposite an instructed left-right hand-movement goal, the Simon effect was reduced. When the wheel was held at the bottom, this reduction was due to some participants coding responses relative to the cursor and others relative to the hands. However, when the wheel was held at the top, it was due to participants integrating cursor movements with hand movements as a single action concept. In contrast, a cursor triggered by the wheel movement showed little influence on the Simon effect, even when contiguity and contingency with the wheel movements were high. Experience with the controlled cursor in a prior trial block or between trials established a causal relation that enabled participants to code the triggered cursor as belonging to the action concept and thus reduce the Simon effect. Multiple factors determine the influence of an irrelevant action effect on performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of visual stimulus mode on transfer of acquired spatial associations.

Associations between corresponding stimulus–response locations are often characterized as overlearned, producing automatic activation. However, 84 practice trials with an incompatible mapping eliminate the benefit for spatial correspondence in a transfer Simon task, where stimulus location is irrelevant. The authors examined whether transfer occurs for combinations of physical-location, arrow-direction, and location-word modes in the practice and transfer sessions. With 84 practice trials, the Simon effect was reduced for locations and arrows, and there was complete transfer across these modes; location words showed little transfer within or between modes. These results suggest that the acquired short-term associations were based on visual-spatial stimulus codes distinct from semantic-spatial codes activated by the words. With 600 practice trials, words showed transfer to word and arrow but not location Simon tasks, suggesting that arrows share semantic-spatial codes with words. Reaction-time distribution functions for the Simon effect showed distinct shapes for each stimulus mode, with little impact of the practiced mapping on the shapes. Thus, the contribution of the short-term location associations seems to be separate from that of the long-term associations responsible for the Simon effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Temporary activation of perceptual–motor associations: A stimulus–response interpretation of automaticity.

Some types of automaticity can be attributed to simple stimulus–response associations (G. D. Logan, 1988). This can be studied with paradigms in which associations to an irrelevant stimulus automatically influence responding to a relevant stimulus. In 1 example, the irrelevant and relevant stimuli were presented successively with the 1st, irrelevant, stimulus masked. Although this stimulus was not phenomenally visible, it influenced responding to the 2nd, visible, stimulus. This influence was substantial only if associations to the 1st stimulus had been activated by recent responding (S. T. Klapp & B. W. Haas, 2005). These associations were not processed deeply; instead, they only relate specific stimuli to specific responses. Whereas these conclusions were demonstrated previously with masking so that participants were not aware of the irrelevant stimulus and thus had no basis to permit control of its influence, the present research demonstrated the same principles when all stimuli were visible. Furthermore, activation of the associations was not subject to substantial intentional control. These findings imply that association-based automaticity occurs independently of, and uninfluenced by, awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Guidance of eye movements during conjunctive visual search: The distractor-ratio effect.

The distractor-ratio effect refers to the finding that search performance in a conjunctive visual search task depends on the relative frequency of two types or subsets of distractors when the total number of items in a display is fixed. Previously, Shen, Reingold, and Pomplun (2000) examined participants' patterns of eye movements in a distractor-ratio paradigm and demonstrated that on any given trial saccadic endpoints were biased towards the smaller subset of distractors and participants flexibly switched between different subsets across trials. The current study explored the boundary conditions of this tendency to flexibly search through a smaller subset of distractors by examining the influence of several manipulations known to modulate search efficiency, including stimulus discriminability (Experiment 1), within-dimension versus cross-dimension conjunction search and distractor heterogeneity (Experiment 2). The results indicated that the flexibility of visual guidance and saccadic bias exemplified by the distractor-ratio effect is a robust phenomenon that mediates search efficiency by adapting to changes in the relative informativeness of stimulus dimensions and features. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Time course of the blindness to response-compatible stimuli.

This article examines the time course of a deficit in identifying a stimulus sharing a compatible feature with a response that is executed in parallel ("blindness to response-compatible stimuli," J. Müsseler & B. Hommel, 1997a). In 5 experiments, participants performed a timed response, and the presentation point of time of a to-be-identified stimulus was varied in respect to response execution. A blindness effect was observed when the stimulus was presented between response cue offset and response execution. In contrast, the identification of a stimulus presented before the response cue or after response execution was not affected by stimulus-response compatibility—a finding that rules out a retention-based explanation. These results support an explanation that states that the perceptual processing of a stimulus feature is impaired as long as the shared perception–action feature code is integrated into the representation of a to-be-executed response. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analyzing the generality of conflict adaptation effects.

Conflict adaptation effects refer to the reduction of interference when the incongruent stimulus occurs immediately after an incongruent trial, compared with when it occurs after a congruent trial. The present study analyzes the key conditions that lead to adaptation effects that are specific to the type of conflict involved versus those that are conflict general. In the first 2 experiments, we combined 2 types of conflict for which compatibility arises from clearly different sources in terms of dimensional overlap while keeping the task context constant across conflict types. We found a clear pattern of specificity on conflict adaptation across conflict types. In subsequent experiments, we tested whether this pattern could be accounted in terms of feature integration processes contributing differently to repetition versus alternation of conflict types. The results clearly indicated that feature integration was not key to generating conflict type specificity on conflict adaptation. The data are consistent with there being separate modes of control for different types of cognitive conflict. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Precueing spatial S-R correspondence: Is there regulation of expected response conflict?

Four experiments investigated the ability to prepare for the level of forthcoming stimulus-response correspondence in choice-response tasks. In a Simon task, participants responded to the color of spatially variable stimuli with spatially variable responses. Participants were given advance information about whether a forthcoming stimulus-response event would be spatially corresponding, neutral, or spatially noncorresponding. Reliable cues decreased reaction times (RTs) in the corresponding conditions of 2- and 3-choice tasks, decreased RTs in noncorresponding conditions of a 2-choice task but not in a 3-choice task, and left RTs in neutral conditions unaffected. The pattern of results suggests that participants used reliable cues for responding to the nominally irrelevant stimulus location if the correct response could be inferred from location (attention switching). By contrast, the lack of cueing effects on performance in noncorresponding conditions of 3-choice tasks suggests that participants cannot use cues for changing the attentional weights of processing channels for different stimulus dimensions (gating). In summary, gating may be involved in the regulation of experienced response conflict, but the present results suggest that it is not involved in the regulation of expected (i.e., predicted) response conflict. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selective attention and distractor frequency in naming performance: Comment on Dhooge and Hartsuiker (2010).

E. Dhooge and R. J. Hartsuiker (2010) reported experiments showing that picture naming takes longer with low- than high-frequency distractor words, replicating M. Miozzo and A. Caramazza (2003). In addition, they showed that this distractor-frequency effect disappears when distractors are masked or preexposed. These findings were taken to refute models like WEAVER++ (A. Roelofs, 2003) in which words are selected by competition. However, Dhooge and Hartsuiker do not take into account that according to this model, picture-word interference taps not only into word production but also into attentional processes. Here, the authors indicate that WEAVER++ contains an attentional mechanism that accounts for the distractor-frequency effect (A. Roelofs, 2005). Moreover, the authors demonstrate that the model accounts for the influence of masking and preexposure, and does so in a simpler way than the response exclusion through self-monitoring account advanced by Dhooge and Hartsuiker. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Response coding and visuomotor transformation in the Simon task: The role of action goals.

Manual responses can be defined by differing response parameters. Any of them may generate a Simon effect. For all those response parameters, the same implementation of the Simon effect (in terms of subserving mechanism) is assumed. In 3 experiments, subjects had to respond with either fingers or sticks. Temporal properties of the Simon effect changed with response parameters relevant in a task. The Simon effect for manual responses decayed. For stick responses, in which the action goal differed from the anatomical mapping of the acting hand, a sustained Simon effect was observed. However, if the action goal for stick responses was not instrumental for selecting the correct response, the Simon effect decayed. The findings are consistent with the notion of different mechanisms involved in generating a Simon effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Need for stimulation as a source of stress response to perceptual isolation.

The study was undertaken to see if Ss who had shown a greater stress reaction to perceptual isolation could be shown to have a greater "need" for stimulation than those who were not so stressed by isolation. Ss selected on the basis of their high or low reactions to the prior isolation experiment were tested in a second 3-hr perceptual isolation situation, only this time they were given the opportunity to make an operant response which would produce random visual or auditory stimulation depending on their choice. Those previously stressed by isolation made significantly more responses for visual and auditory reinforcement than the low-stress group. All Ss responded more for visual than for auditory reinforcement. (29 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)