Visualizing the temporal dynamics of spatial information processing responsible for the Simon effect and its amplification by inhibition of return

Research has shown that the Simon effect is larger for targets suffering from inhibition of return (IOR). We used speed–accuracy trade-off (SAT) methodology to explore the temporal dynamics underlying this interaction. In Experiment 1, a new method for sorting the data was used to reveal a monotonic decay in the impact of task-irrelevant location information that is responsible for the Simon effect. In Experiment 2, we show that IOR delays both task-relevant identity and task-irrelevant location codes; a relatively longer delay for location than identity codes accounts for the effect of IOR on the Simon effect. When location information was made task-relevant in Experiment 3, IOR delayed the accumulation of this information by about the same amount as when location was irrelevant. The results suggest that IOR, therefore, has a greater effect on location than identity information.     

Mind-wandering: phenomenology and function as assessed with a novel experience sampling method

Mind-wandering refers to the occurrence of thoughts whose content is both decoupled from stimuli present in the current environment and unrelated to the task being carried out at the moment of their occurrence. The core of this phenomenon is therefore stimulus-independent and task-unrelated thoughts (SITUTs). In the present study, we designed a novel experience sampling method which permitted to isolate SITUTs from other kinds of distractions (i.e., irrelevant interoceptive/exteroceptive sensory perceptions and interfering thoughts related to the appraisal of the current task). In Experiment 1, we examined the impact of SITUTs on the performance of the Sustained Attention to Response Task (SART; a Go/No-Go task). Analyses demonstrated that SITUTs impair SART performance to the same extent as irrelevant sensory perceptions. In Experiment 2, we further examined SITUTs in order to assess the possible functions of mind-wandering. We observed that the content of most of reported SITUTs refers to the anticipation and planning of future events. Furthermore, this “prospective bias” was increased when participants' attention had been oriented toward their personal goals before performing the SART. These data support the view that an important function of mind-wandering relates to the anticipation and planning of the future.     

Cognitive control in number processing: evidence from the unit-decade compatibility effect

In this study we evaluated whether the reverse compatibility effect observed when participants compare two-digit Spanish number words might be modulated as a function of the percentage of filler trials (within-decade comparisons). The participants performed a comparison task with two-digit Spanish number words while the unit–decade compatibility in between decade comparison trials was manipulated. We biased the relevance of units by increasing the intra/inter decade comparison ratio (20%, 50%, and 70%). The compatibility effect shifted from reverse to regular depending on the unit relevance which indicates that the relative emphasis on the unit processing in two-digit number word can be modulated by the stimulus list. These results are discussed in terms of cognitive control in number processing.     

Cue type affects preparatory influences on task inhibition

The present study investigates the influence of preparation on inhibitory effects in cued task switching. In three experiments, we assessed n − 2 repetition costs as marker of inhibition of the just executed and now irrelevant task by comparing performance in task sequences such as ABA (i.e., n − 2 repetitions, with A, B and C standing for different tasks) to task sequences such as CBA (i.e., n − 2 switches). Specifically, we varied the cue–target interval (CTI) to examine cue-based preparation effects. In addition, we manipulated cue type (i.e., abstract, verbal, and direct cues) across the three experiments. We obtained significant reductions of n − 2 repetition costs with prolonged CTI when using abstract cues (i.e., coloured frames) and task names (i.e., digit), but not when using the task-specific stimulus–response mapping as cue for the upcoming task. These data suggest that cue-based preparation is not a uniform process but depends on the information provided by the cue.     

Involvement of shared resources in time judgment and sequence reasoning tasks

Previous research suggests that time perception is supported by the same attentional resources involved in sequence processing. The present experiment was designed to clarify this connection by examining the relation between timing and reasoning tasks that involved either sequencing or non-sequencing judgments. For the timing task, subjects produced a series of 5-s intervals. For the reasoning tasks, subjects judged whether pairs of statements describing common actions either (a) were presented in the correct temporal order (sequencing), or (b) described similar actions or objects (similarity). Subjects performed the timing and reasoning tasks both separately and concurrently in a series of 3-minute trials. Comparisons of single-task and dual-task performance assessed interference patterns between concurrent tasks. Both reasoning tasks interfered with timing by making temporal productions longer and more variable. Timing had differential effects on the two reasoning tasks. Concurrent timing caused sequencing judgments to become slower, less accurate, and less sensitive relative to sequencing-only conditions. In contrast, similarity judgments were either unaffected or affected to a lesser degree by the concurrent timing task. These results support the notion that timing and sequencing are closely related processes that rely on the same set of cognitive resources or mechanisms.     

Differential dynamics of spatial and non-spatial stimulus-response compatibility effects: a dual task LRP study

Choice reaction times are shorter when stimulus and response features are compatible rather than incompatible. Recent studies revealed that spatial compatibility effects in Simon tasks are strongly attenuated when there is temporal overlap with a different high-priority task. In contrast, non-spatial variants of the Simon task appear to be unaffected by task overlap. The present study used the lateralized readiness potential (LRP) within a dual task design to elucidate the dynamics underlying these differential effects for a color and a spatial variant of the Simon task. In the color version there was no sign of early response priming by irrelevant stimulus features in the LRP. The color compatibility effect was independent of task overlap and reflected in the LRP onset latency. In contrast, in the spatial version, priming by irrelevant stimulus location showed up and was mirrored by early LRP activation. Response priming and the corresponding Simon effect, however, were present only in case of little temporal overlap with the primary task. The absence of spatial compatibility effects at strong temporal overlap suggests that response conflicts due to stimulus-related priming depend on the availability of processing resources.     

The premotor theory of attention and the Simon effect

In the paper by Hommel (2011-this issue), the roles of the theory of event coding (TEC) and the premotor theory of attention (PMTA) for the Simon effect were considered. PMTA was treated by Hommel in terms of the proposal that attentional orienting can be viewed as the preparation of a saccade towards a certain location, and was dismissed as providing no useful contribution for an attentional explanation of the Simon effect. Here we considered a more recent and broader conception of the PMTA, compared this approach with TEC, and confronted both approaches with a few studies focusing on the role of spatial attention for the Simon effect. It was argued that PMTA may account more easily for various studies examining the influence of spatial attention on the Simon effect. We concluded our paper by listing some elements that an overall encompassing theory on the Simon effect should contain.     

The components of visual attention and the ubiquitous Simon effect

Spatial responding is influenced by the degree of correspondence between the stimulus–response (S–R) code activated by the target's task-irrelevant location and the S–R code activated by the target's non-spatial, task-relevant feature. A generally accepted explanation of this “Simon effect,” named after its discoverer, is that there is a natural tendency to respond towards the source of stimulation. First we will review the ubiquity of the Simon effect. Then we will review the literature, including our own studies when appropriate, that has explored the relationship between the Simon effect and the components of attention: alertness, orienting and executive control, with an emphasis on visual orienting. The Simon effect is reduced when participants are not alert and when executive control is effective in filtering out the irrelevant location information. When attention is oriented endogenously, or is captured exogenously by uninformative peripheral stimulation, the Simon effect is additive with attentional facilitation (i.e., the Simon effect is the same magnitude for targets presented at attended and unattended locations). Yet, some forms of orienting, such as orienting directed by gaze and biased by inhibition of return, modulate the Simon effect. We will explore the implications of these patterns of additivity and interaction for our understanding of both the Simon effect and spatial attention.     

The Simon effect as tool and heuristic

On its 43rd anniversary the Simon effect can look back at a long and varied history. First treated as a curious observation with implications for human factors research, it slowly evolved not only into a valuable target of psychological theorizing itself but also into a handy means to investigate attentional operations, the representation of space and of one's body, the cognitive representation of intentional action, and executive control. This article discusses the major characteristics of the Simon effect and the Simon task that laid the ground for this success and reviews the major lines of research, theoretical developments, and ongoing controversies on and around the Simon Effect and the cognitive processes it reflects.     

The Simon effect in cognitive electrophysiology: A short review

In the Simon task, stimuli are presented laterally and typically a non-spatial stimulus dimension demands a lateralized choice response. Responses are faster when the task-irrelevant stimulus location and the response location correspond than when they do not correspond. The present paper explores the impact of the Simon task on cognitive electrophysiological research as well as the insights gained from event-related brain potentials (ERPs) in the attempt to uncover the hidden mechanisms underlying the Simon effect.     

Keeping Simon simple: Examining the relationship between sequential modulations and feature repetitions with two stimuli, two locations and two responses

The present study examined performance across three two-choice tasks that used the same two stimuli, the same two stimulus locations, and the same two responses to determine how task demands can alter the Simon Effect, its distribution across reaction time, and its sequential modulation. In two of the tasks, repetitions of stimulus features were not confounded with sequences of congruent and incongruent trials. This attribute allowed us to investigate the sequential modulation of the Simon Effect in a two-choice task while equalizing the occurrence of feature repetitions. All tasks showed a similar sequential modulation, suggesting that it is not driven by feature repetitions. Moreover, distributional analyses revealed that the advantage for congruent trials decreased as reaction time increased similarly following congruent and incongruent trials. Finally, a large increase in RT was observed when repeated responses were made to novel stimuli and when novel responses were made to repeated stimuli. This effect also showed a sequential modulation regardless of whether the stimulus repeated. The findings suggest that, even in two-choice tasks, response selection is mediated by complex, dynamic representations that encode abstract properties of the task rather than just simple features.     

Attention orienting by eye gaze and arrows reveals flexibility to environmental changes

This study aimed to evaluate the difference in non-predictive cues between gaze and arrows in attention orienting. Attention orienting was investigated with gaze or arrows as separate cues in a simple condition (i.e., block design) in Experiment 1 and in an unpredictable condition (i.e., randomized design) in Experiment 2. Two kinds of sound (voice and tone) stimuli were used as targets. Results showed that gaze and arrow cues induced enhanced attention orienting to a voice versus tone target in the block condition. However, in the randomized condition, enhanced attention orienting to a voice versus tone target was found in gaze but not arrow cues. The congruency of the meaning between a social cue (i.e., gaze) and a social target (i.e., voice) was clear in the randomized but not blocked design, because social gaze and non-social arrow cues were implemented in the same block. Thus, attention orienting might be mediated by the associated relationship of cue–target in a randomized condition, as an enhanced orienting effect was found when the associated relationship of cue–target was strong (i.e., social cue and target). The present study suggests that the difference in attention orienting between gaze and arrows is apparent in a randomized design (the unpredictable condition), and people employ a flexibly strategy of orienting to better respond to environmental changes.     

Intentional Binding is independent of the validity of the action effect's identity

When an action produces an effect, both events are perceived to be shifted in time toward each other. This shift is called Intentional Binding (IB) effect. First evidence shows that this shift does not depend on the statistical predictability of the produced effect's identity (Desantis, Hughes, & Waszak, 2012). We confirm this result by comparing the perceived duration of action–effect intervals before valid and invalid action effects using the method of constant stimuli. The perceived duration of action–effect intervals did not differ for valid and invalid effects. This result was true for different durations of the action–effect interval (Experiments 1–4: 250 ms, Experiments 1 & 2: 400 ms), different effect modalities (Experiments 1 & 3: visual, Experiments 2–4: auditive), and two types of validity variations (Experiments 1 & 2: 80% valid, Experiments 3 & 4: 100% valid vs. random). We validated our results by using a clock paradigm and a numerical duration estimation task (Experiment 4). We conclude that the IB effect is not the result of internal prediction due to action–effect bindings, but might rely on higher-order processes.     

Perceptual complexity,rather than valence or arousal accounts for distracter-induced overproductions of temporal durations

For humans and other species, the ability to estimate the physical passage of time is of fundamental importance for perceptual, cognitive or motor functions. Despite this importance, any subjective estimation of temporal durations not only depends on the temporal dynamics of the to-be-timed stimulus or event, but also can be distorted by non-temporal perceptual, cognitive, and emotional effects. This study aimed to further explore critical stimulus characteristics modulating distracter-induced distortions in human time-reproduction. To this end, we investigated whether subjectively rated distracter dimensions of arousal and valence (related to levels of emotionality), or rather stimulus complexity, as a confounder, produce distortions in participants' reproduction of a previously trained target interval. Accuracy and precision of time-reproduction have been measured in distracter-trials, and compared to timing performance in baseline-trials without any distraction. Results showed temporal overproductions in a magnitude of less than distracter duration only for complex distracters. Most importantly, arousal level and valence of distracters were not accountable for temporal distortions. Within an internal clock framework, our pattern of results can best be interpreted in the context of attention-, rather than arousal-based mechanisms of timing.     

Now you see it, now you don't: controlling for contingencies and stimulus repetitions eliminates the Gratton effect

The Gratton (or sequential congruency) effect is the finding that conflict effects (e.g., Stroop and Eriksen flanker effects) are larger following congruent trials relative to incongruent trials. The standard account given for this is that a cognitive control mechanism detects conflict when it occurs and adapts to this conflict on the following trial. Others, however, have questioned the conflict adaptation account and suggested that sequential biases might account for the Gratton effect. In two experiments, contingency biases were removed from the task and stimulus repetitions were deleted to control for stimulus bindings. This eliminated the Gratton effect in the response times in both experiments, supporting a non-conflict explanation of the Gratton effect. A Gratton effect did persist in the errors of Experiment 1; however, this effect was not produced by the type of errors (word reading errors) that a conflict adaptation account should predict. Instead, tentative support was found for a congruency switch cost hypothesis. In all, the conflict adaptation account failed to account for any of the reported data. Implications for future work on cognitive control are discussed.     

Language access and language selection in professional translators

Two experiments were conducted measuring self-paced reading to study language access and language selection in professional translators and bilinguals when they understood sentences randomly presented in their first language (L1, Spanish) and second language (L2, English). These sentences contained a critical cognate word or a control matched word. The effect of cognate words was considered an index of between-language activation while the inhibition of the non-target language was examined with the asymmetrical switching cost. In Experiment 1, participants read and repeated sentences while in Experiment 2 participants read sentences without repeating them after reading. The results indicated that lexical processing depended on the experience of participants in professional translation and the demands imposed by the understanding task (reading and repeating or only reading).     

Conflict and error adaptation in the Simon task

We present recent empirical and theoretical advances in conflict and error monitoring in the Simon task. On the basis of the adaptation by binding account for conflict adaptation and the orienting account for post-error slowing, we predict a dissociation between conflict and error monitoring. This prediction is tested and confirmed as conflict adaptation is task-specific while post-error slowing is not.     

Using the visual world paradigm to study language processing: a review and critical evaluation

We describe the key features of the visual world paradigm and review the main research areas where it has been used. In our discussion we highlight that the paradigm provides information about the way language users integrate linguistic information with information derived from the visual environment. Therefore the paradigm is well suited to study one of the key issues of current cognitive psychology, namely the interplay between linguistic and visual information processing. However, conclusions about linguistic processing (e.g., about activation, competition, and timing of access of linguistic representations) in the absence of relevant visual information must be drawn with caution.     

Unintentional and intentional learning of noncorresponding stimulus-response associations in the Simon task

The Simon effect is a robust phenomenon that persists after extensive practice. However, several studies using a transfer paradigm have shown that the Simon effect is eliminated after practicing a location-relevant task with an incompatible spatial mapping. The present study examined whether this transfer effect is a result of implicit, procedural knowledge developed through repeated execution of noncorresponding responses in the practice session or a consequence of explicitly learning and reinstating a noncorresponding mapping rule. Results from two experiments show that, although a small part of the transfer effect may be due to residual activation of noncorresponding S-R associations from the prior task, the larger and more stable part is likely due to response-selection strategies performed intentionally in the practice task.     

Efficiency and interactions of alerting,orienting and executive networks: The impact of imperative stimulus type

The Attention Network Test (ANT) generates measures of three attention networks: alerting, orienting and executive control. Arrows have been generally used as imperative stimuli in the different versions of this paradigm. However, it is unknown whether the directional nature of these stimuli can modulate the efficiency of the executive control and its interaction with alerting and orienting. We developed three ANT variants to examine attentional effects in response to directional and non-directional stimuli. Arrows (ANTI-A), colored fruits (ANTI-F) and black geometrical-shape (ANTI-G) were used as imperative stimuli (i.e., flanker stimuli). Data collected from fifty-two university students, in two experiments, showed that arrows stimuli produced a greater interference effect and a greater orienting effect as compared to the other stimuli. Moreover, only arrows modulated the interaction between executive control and orienting: a reduced flanker effect in spatially cued trials was only observed in ANTI-A. These results suggest that the directional value of the stimuli increases the conflict and modulates the efficiency of executive control and its interaction with orienting network.