Spatial Stroop Task Research Articles

Asymmetry of congruency effects in spatial Stroop tasks can be eliminated

Three experiments examined whether asymmetry in interference can be eliminated in spatial Stroop tasks. In Experiment 1, responding to arrows or location words written in Chinese and to their locations created spatial Stroop effects of similar sizes. In Experiment 2, responding to a location word embedded in an outline drawing of arrow did not yield a spatial Stroop effect, but responding to the arrow's direction did yield an effect. In Experiment 3, responding to a location word flanked by an arrow and to the arrow rather than the word produced similar sizes of spatial Stroop effects. These results show that asymmetry in spatial Stroop interference can be eliminated in some situations. Although aspects of the results are consistent with predictions of translation and dimensional overlap models, they are in closest agreement overall with an account in terms of the relative strengths of the relevant and irrelevant stimulus–response associations.

The social emotional developmental and cognitive neuroscience of socioeconomic gradients: laboratory, population, cross-cultural and community developmental approaches

The social emotional developmental and cognitive neuroscience of socioeconomic gradients: laboratory, population, cross-cultural and community developmental approaches

The generalization of block-wise conflict adaptation between Simon and Spatial Stroop tasks

The generalization of block-wise conflict adaptation between Simon and Spatial Stroop tasks

High cognitive reserve is associated with a reduced age-related deficit in spatial conflict resolution.

Several studies support the existence of a specific age-related difficulty in suppressing potentially distracting information. The aim of the present study is to investigate whether spatial conflict resolution is selectively affected by aging. The way aging affects individuals could be modulated by many factors determined by the socieconomic status: we investigated whether factors such as cognitive reserve (CR) and years of education may play a compensatory role against age-related deficits in the spatial domain. A spatial Stroop task with no feature repetitions was administered to a sample of 17 non-demented older adults (69–79 years-old) and 18 younger controls (18–34 years-old) matched for gender and years of education. The two age groups were also administered with measures of intelligence and CR. The overall spatial Stroop effect did not differ according to age, neither for speed nor for accuracy. The two age groups equally showed sequential effects for congruent trials: reduced response times (RTs) if another congruent trial preceded them, and accuracy at ceiling. For incongruent trials, older adults, but not younger controls, were influenced by congruency of trialn−1, since RTs increased with preceding congruent trials. Interestingly, such an age-related modulation negatively correlated with CR. These findings suggest that spatial conflict resolution in aging is predominantly affected by general slowing, rather than by a more specific deficit. However, a high level of CR seems to play a compensatory role for both factors.

The error-related negativity associated with different strength of stimulus–response interference

ObjectiveThe present study was aimed at clarifying the effect of stimulus–response compatibility (SRC) interference on the ERN. MethodsWe compared ERNs in two tasks differing in the level of interference, an arrow (AR) task classified as a Simon task and a more complex arrow-orientation (AO) task classified as a spatial-Stroop task. We also compared ERNs between partial errors (with initial incorrect movement corrected by a proper full response) and overt (uncorrected) errors. ResultsBehavioral response time and error rate indicated that both interference and ERN amplitude were larger for the AO task than for the AR task. There was no significant difference in the ERN amplitude between the partial and overt errors. ConclusionsThe ERN becomes larger as a function of the SRC interference. SignificanceOur study presented evidence that the ERN may represent response-monitoring associated with the SRC interference.

The influence of emotions due to verbal admonishment and encouragement on performance monitoring

This study investigated the relationship between emotion and performance monitoring as reflected in the error negativity/error-related negativity (Ne/ERN). Data were collected by using a spatial Stroop task from 15 female students of a university tennis club. After errors, participants received verbal feedback-recorded admonishments or encouragements spoken by their team captain. In a control condition no feedback was given after errors. Verbal admonishment decreased the ERN relative to the control condition, indicating impaired performance monitoring in line with somewhat larger compatibility effects in this condition. Source localization indicated a shift of the ERN toward more rostral zones within the anterior cingulate cortex indicating the involvement of affective processes.

The Two Sides of Temporal Orienting

Would it be helpful to inform a driver about when a conflicting traffic situation is going to occur? We tested whether temporal orienting of attention could enhance executive control to select among conflicting stimuli and responses. Temporal orienting was induced by presenting explicit cues predicting the most probable interval for target onset, which could be short (400 ms) or long (1,300 ms). Executive control was measured both by flanker and Simon tasks involving conflict between incompatible responses and by the spatial Stroop task involving conflict between perceptual stimulus features. The results showed that temporal orienting facilitated the resolution of perceptual conflict by reducing the spatial Stroop effect, whereas it interfered with the resolution of response conflict by increasing flanker and Simon effects. Such opposite effects suggest that temporal orienting of attention modulates executive control through dissociable mechanisms, depending on whether the competition between conflicting representations is located at perceptual or response levels.

Word and position interference in stroop tasks: a behavioral and fMRI study

One of the main features of the attentional system is the capability to select between relevant and irrelevant information. However, irrelevant information interferes with the processing of the relevant one. Using high-field magnetic resonance imaging, we examined the interference effect of a verbal (color-word) and a spatial (arrow-position) Stroop task on the activation of cortical areas known to be dedicated to the attentional control. Behaviorally, we found costs from the irrelevant information in both tasks; in the brain, we found a common neural network of activation that mainly involved the dorsolateral prefrontal cortex and the anterior cingulate cortex. However, the neural circuits involved in the two tasks overlapped only partially, since processing of words in the color-word Stroop task showed a wider and more right-lateralized activation, while spatial processing in the arrow-position Stroop task resulted in a more restricted and left-lateralized activation.

Thinking about the future moves attention to the right.

Previous studies have shown that past and future temporal concepts are spatially represented (past being located to the left and future to the right in a mental time line). This study aims at further investigating the nature of this space-time conceptual metaphor, by testing whether the temporal reference of words orient spatial attention or rather prime a congruent left/right response. A modified version of the spatial cuing paradigm was used in which a word's temporal reference must be kept in working memory whilst participants carry out a spatial localization (Experiment 1) or a direction discrimination, spatial Stroop task (Experiment 2). The results showed that the mere activation of the past or future concepts both oriented attention and primed motor responses to left or right space, respectively, and these effects were independent. Moreover, in spite of the fact that such time-reference cues were nonpredictive, the use of a short and a long stimulus onset asynchrony in Experiment 3 showed that these cues modulated spatial attention as typical central cues like arrows do, suggesting a common mechanism for these two types of cuing.

Sustained vs. transient cognitive control: Evidence of a behavioral dissociation

This study assessed whether two well known effects associated with cognitive control, conflict adaptation (the Gratton effect) and conflict context (proportion congruent effects), reflect a single common or separate control systems. To test this we examined if these two effects generalized from one kind of conflict to another by using a combined-conflict paradigm (involving the Simon and Spatial Stroop tasks) and manipulating the proportion of congruent to incongruent trials for one conflict (Simon) but not the other (Spatial Stroop). We found that conflict adaptation effects did not generalize, but the effect of conflict context did. This contrasting pattern of results strongly suggests the existence of two separate attentional control systems, one transient and responsible of online regulation of performance (conflict adaptation), the other sustained and responsible for conflict context effects.

Cognitive inhibitory control and self-reported impulsivity among violent offenders with schizophrenia

There is evidence for reduced cognitive inhibitory control in schizophrenia, but associated behavioral consequences are unclear. In an investigation of the link between cognitive inhibition and impulsive behavior, violent offenders with schizophrenia (n = 18) and healthy adults completed spatial Stroop and negative priming tasks and the Barratt Impulsiveness Scale (a self-report impulsivity measure). Negative priming (but not Stroop) was impaired among violent offenders with schizophrenia, but there was no association between reduced inhibition and impulsivity. While these findings should be interpreted with caution, cognitive inhibition in schizophrenia may be unrelated to impulsive behaviors that are commonly linked to violent offending.

Preparatory neural activity predicts performance on a conflict task

Advance preparation has been shown to improve the efficiency of conflict resolution. Yet, with little empirical work directly linking preparatory neural activity to the performance benefits of advance cueing, it is not clear whether this relationship results from preparatory activation of task-specific networks, or from activity associated with general alerting processes. Here, fMRI data were acquired during a spatial Stroop task in which advance cues either informed subjects of the upcoming relevant feature of conflict stimuli (spatial or semantic) or were neutral. Informative cues decreased reaction time (RT) relative to neutral cues, and cues indicating that spatial information would be task-relevant elicited greater activity than neutral cues in multiple areas, including right anterior prefrontal and bilateral parietal cortex. Additionally, preparatory activation in bilateral parietal cortex and right dorsolateral prefrontal cortex predicted faster RT when subjects responded to spatial location. No regions were found to be specific to semantic cues at conventional thresholds, and lowering the threshold further revealed little overlap between activity associated with spatial and semantic cueing effects, thereby demonstrating a single dissociation between activations related to preparing a spatial versus semantic task-set. This relationship between preparatory activation of spatial processing networks and efficient conflict resolution suggests that advance information can benefit performance by leading to domain-specific biasing of task-relevant information.

Reaction Time Inconsistency in a Spatial Stroop Task: Age-Related Differences Through Childhood and Adulthood

ABSTRACT Age-related differences in inconsistency of reaction time (RT) across the life span were examined on a task with differing levels of demand on executive control. A total of 546 participants, aged 5 to 76 years, completed a spatial Stroop task that permitted observations under three conditions (congruent, incongruent, and neutral) according to the correspondence between the required response (based on stimulus direction) and stimulus location. An interference effect was observed across all ages. Analyses of neutral condition data replicated previous research demonstrating RT inconsistency follows a U-shaped developmental curve across the life span. The relationship between age and inconsistency, however, depended on condition: inconsistency in the congruent condition was higher than inconsistency in both the neutral and incongruent conditions across middle-aged groups. Reaction time inconsistency may reflect processing efficiency that is maximal in young adulthood and may also be sensitive to fluctuations in performance that reflect momentarily highly efficient responding.

An Electrophysiological Investigation of Preparatory Attentional Control in a Spatial Stroop Task

Top-down attentional control is required when subjects must attend to one of multiple conflicting stimulus features, such as in the Stroop task. Performance may be improved when such control is implemented in advance of stimulus presentation, yet few studies have examined this issue. Our investigation employed a spatial Stroop task with a manual response, allowing us to focus on the effects of preparatory attention on verbal processing when it is the less automatic attribute. A letter cue (P or W) presented for 2200 msec instructed subjects to respond on the basis of the position or meaning of a word (up, down, left, right) placed in an incongruent position relative to center. Event-related potentials recorded during pre- and poststimulus periods were analyzed as a function of reaction time to the target stimulus (fast vs. slow) in order to differentiate neural activity associated with more or less successful implementation of control. During the prestimulus period, fast responses to subsequent targets were associated with enhanced slow-wave activity over right frontal and bilateral central-parietal regions. During the poststimulus period, fast word trials were uniquely associated with an enhanced inferior temporal negativity (ITN) from 200 to 600 msec. More importantly, a correlation between frontal prestimulus activity and the poststimulus ITN suggested that frontal preparatory activity played a role in facilitating conceptual processing of the verbal stimulus when it arrived, providing an important link between preparatory attention and mechanisms that improve performance in the face of conflict.

Effects of stimulus–stimulus compatibility and stimulus–response compatibility on response inhibition

Previous studies demonstrated that interference control in stimulus–stimulus compatibility tasks slowed down stopping in the stop signal task (e.g., Kramer, A. F., Humphrey, D. G., Larish, J. F., Logan, G. D., & Strayer, D. L. (1994). Aging and inhibition: beyond a unitary view of inhibitory processing in attention. psychology and aging, 9, 491–512). In the present study, the impact of stimulus–stimulus compatibility and stimulus–response compatibility on response inhibition is further investigated. In Experiment 1, the stop signal task was combined with a traditional horizontal Simon task and with a vertical variant. For both dimensions, stopping responses was prolonged in incompatible trials, but only when the previous trial was compatible. In Experiment 2, the Simon task was combined with a spatial Stroop task in order to compare the effects of stimulus–stimulus and stimulus–response compatibility. The results demonstrated that both types of compatibility influenced stopping in a similar way. These findings are in favor of the hypothesis that response inhibition in the stop signal task and interference control in conflict tasks rely on similar mechanisms.

Dissociations among tasks involving inhibition: A single-case study

Recent theories of working memory have emphasized the role of inhibition in suppressing irrelevant information. Moreover, psychometric studies have reported that several inhibition tasks with very diverse requirements load on a single inhibition factor. A patient with left inferior frontal damage, Patient M.L., previously reported to have a semantic short-term memory deficit (R. C. Martin & He, 2004), showed evidence of difficulty with inhibition on short-term memory tasks. We investigated whether he would show evidence of inhibition difficulty on two verbal tasks (a Stroop task and a recent-negatives task) and two nonverbal tasks (a nonverbal spatial Stroop task and an antisaccade task). M.L. was impaired on both verbal tasks but performed normally on the nonverbal tasks. M.L.'s data also represent a dissociation between Stroop and antisaccade performance, two tasks that load on a single factor in factor-analytic studies. The implications of these data for theories of inhibition and executive function are discussed.

Common and distinct neural substrates of attentional control in an integrated Simon and spatial Stroop task as assessed by event-related fMRI

The purpose of this experiment was to directly examine the neural mechanisms of attentional control involved in the Simon task as compared to a spatial Stroop task using event-related fMRI. The Simon effect typically refers to the interference people experience when there is a stimulus–response conflict. The Stroop effect refers to the interference people experience when two attributes of the same stimulus conflict with each other. Although previous imaging studies have compared the brain activation for each of these tasks performed separately, none had done so in an integrated task that incorporates both types of interference, as was done in the current experiment. Both tasks activated brain regions that serve as a source of attentional control (dorsolateral prefrontal cortex) and posterior regions that are sites of attentional control (the visual processing stream–middle occipital and inferior temporal cortices). In addition, there were also specific brain regions activated to a significantly greater degree by one task and/or only by a single task. The brain regions significantly more activated by the Simon task were those sensitive to detection of response conflict, response selection, and planning (anterior cingulate cortex, supplementary motor areas, and precuneus), and visuospatial–motor association areas. In contrast, the regions significantly more activated by the Stroop task were those involved in biasing the processing toward the task-relevant attribute (inferior parietal cortex). These findings suggest that the interference effects of these two tasks are caused by different types of conflict (stimulus–response conflict for the Simon effect and stimulus–stimulus conflict for the Stroop effect) but both invoke similar sources of top-down modulation.

When in Doubt, Do it Both Ways: Brain Evidence of the Simultaneous Activation of Conflicting Motor Responses in a Spatial Stroop Task

Response competition is often considered an important contributor to the delayed reaction to stimuli for which physical and semantic information are in conflict ("Stroop" effect). Response competition implies that brain areas associated with correct and incorrect responses (e.g., left and right motor cortices) should be simultaneously activated in conflict conditions. However, there is at present little direct evidence of this phenomenon, in part because of the paucity of brain imaging techniques that can independently monitor the time course of activation of adjacent brain areas, such as the motor areas. In the present study, we show that the event-related optical signal (EROS) can provide these types of data. The results confirm the prediction that conflict trials elicit simultaneous activation of both motor cortices, whereas nonconflict trials elicit brain activity only in the contralateral motor cortex. These data support a parallel view of the human information processing system.

Different error types and error processing in spatial stimulus-response-compatibility tasks: behavioural and electrophysiological data

We tested the hypothesis that in spatial stimulus-response-compatibility (SRC) tasks two different error types occur: A noise-induced ‘general error’ independent of SRC and reaction time and a ‘position driven error’ in incompatible trials with short RT being driven by the irrelevant stimulus position. A second issue was whether error detection is different for these two types of errors, which should be reflected by differences in the error negativity (Ne), since the Ne is seen as a neural correlate of error detection. To study these issues, we used a Simon- and a spatial Stroop-task. In incompatible (vs. compatible) trials we found more errors and a below chance accuracy in fast responses. Neither the amplitude nor the latency of the Ne were significantly affected by the experimental factors. This pattern of behavioural results supports the above hypothesis of two error types in such tasks. The Ne results indicate that error detection is similar for both types of errors.

Increased attention to the irrelevant dimension increases interference in a spatial Stroop task.

Abstract In a spatial version of the Stroop task where subjects must attend to the position of a word and ignore the word itself, we argue that interference results because selective attention is only partially successful. If so, then increasing attention to the word should increase interference. Experiment 1 showed increased interference with position naming when subjects must be prepared to attend to either the word or its position. Experiment 2 required subjects to first name the position of the word and then later to recall which word had been presented. This resulted in increased interference with position naming when the word was followed at a short SOA by a pattern mask. Experiment 3 employed both word reading and position naming and showed that a large reverse Stroop effect occurred with both vocal and manual responses when subjects had to be prepared to attend to either dimension of the stimulus.In a typical Stroop task, a word is presented to a subject and the subject is required either to read the word or to report some other attribute of the word, such as its colour or position. In the latter case, response times are strongly influenced by whether the word and the attribute to be reported are congruent or incongruent. For example, when subjects are asked to report whether the stimulus words left, right, above or below are located to the left, to the right, above or below a fixation point, responding is faster if the stimulus word and its position are congruent, and is slower if the stimulus word and its position differ (Seymour, 1973). On the other hand, if the word is to be named, the congruity or incongruity of the spatial attribute of the word has little effect on response time. The word naming situation has often been referred to as the reverse Stroop condition.Interference effects in the Stroop task have frequently been attributed to a failure of selective attention in that subjects seem to be unable to avoid processing the stimulus word. Treisman (1969) has attributed this failure of attention to an inability to selectively attend to different dimensions of an object. On the other hand, there are data which indicate that Stroop interference may not simply reflect a breakdown of selective attention, because the amount of interference can be influenced by the way attention is deployed. Francolini and Egeth (1980) presented their subjects with a circular array containing a variable number of red and black items and asked them to report the number of red items. When the red items were digits which were inconsistent with the number of red items, reaction times were longer, but when the to-be-ignored black items were inconsistent digits, no interference was obtained. Kahneman and Henik (1981) presented their subjects with two words, one on either side of the fixation point. One of the words was printed in coloured ink and the other was printed in black. Subjects were instructed to ignore the black word and report the colour of the other word. When the non-black word was an incompatible colour word, the usual Stroop interference effects were obtained, but no interference was obtained when the to-be-ignored black word was an incompatible colour word. These studies indicate that when attention is directed elsewhere in the visual field, words or numbers are not automatically processed to the extent necessary to produce Stroop interference.There is also evidence that subjects may be able to focus attention on one dimension of a stimulus object and ignore other dimensions. Harvey (1984, Experiment 4) presented a cue (X or x) followed by the words HI or LO in congruent or incongruent positions. The case of the cue indicated whether the subject was to report the position of the word or name it. The interstimulus interval (ISI) between the cue and the word varied from 50 to 950 ms. For both the position and word naming tasks, responses were slower on incongruent trials, but this effect declined with ISI. …