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Avishai Henik - One of the best experts on this subject based on the ideXlab platform.
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Dissociation between reaction time and pupil dilation in the Stroop Task.
Journal of experimental psychology. Learning memory and cognition, 2019Co-Authors: Ronen Hershman, Avishai HenikAbstract:It has been suggested that the Stroop Task gives rise to 2 conflicts: the information conflict (color vs. word meaning) and the Task conflict (name the color vs. read the word). However, behavioral indications for Task conflict (reaction time [RT] congruent condition longer than RT neutral condition) appear under very restricted conditions. We conducted Stroop experiments and measured RT and pupil dilation. The results show a clear dissociation between RT and pupil dilation. We found the regular RT pattern-large interference and small, nonsignificant facilitation. In contrast, pupil dilation showed information conflict-larger pupil dilation to incongruent than to congruent and neutral conditions-and Task conflict-larger pupil dilation to the congruent than to the neutral condition. Moreover, pupil indications for Task conflict appeared earlier than indications for the information conflict. These results suggest that pupil changes could indicate conflict even in the absence of behavioral indications for the conflict. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
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Task conflict and proactive control a computational theory of the Stroop Task
Psychological Review, 2017Co-Authors: Eyal Kalanthroff, Eddy J. Davelaar, Avishai Henik, Liat Goldfarb, Marius UsherAbstract:The Stroop Task is a central experimental paradigm used to probe cognitive control by measuring the ability of participants to selectively attend to Task-relevant information and inhibit automatic Task-irrelevant responses. Research has revealed variability in both experimental manipulations and individual differences. Here, we focus on a particular source of Stroop variability, the reverse-facilitation (RF; faster responses to nonword neutral stimuli than to congruent stimuli), which has recently been suggested as a signature of Task conflict. We first review the literature that shows RF variability in the Stroop Task, both with regard to experimental manipulations and to individual differences. We suggest that Task conflict variability can be understood as resulting from the degree of proactive control that subjects recruit in advance of the Stroop stimulus. When the proactive control is high, Task conflict does not arise (or is resolved very quickly), resulting in regular Stroop facilitation. When proactive control is low, Task conflict emerges, leading to a slow-down in congruent and incongruent (but not in neutral) trials and thus to Stroop RF. To support this suggestion, we present a computational model of the Stroop Task, which includes the resolution of Task conflict and its modulation by proactive control. Results show that our model (a) accounts for the variability in Stroop-RF reported in the experimental literature, and (b) solves a challenge to previous Stroop models-their ability to account for reaction time distributional properties. Finally, we discuss theoretical implications to Stroop measures and control deficits observed in some psychopathologies. (PsycINFO Database Record
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evidence for interaction between the stop signal and the Stroop Task conflict
Journal of Experimental Psychology: Human Perception and Performance, 2013Co-Authors: Eyal Kalanthroff, Liat Goldfarb, Avishai HenikAbstract:Performance of the Stroop Task reflects two conflicts--informational (between the incongruent word and ink color) and Task (between relevant color naming and irrelevant word reading). The Task conflict is usually not visible, and is only seen when Task control is damaged. Using the stop-signal paradigm, a few studies demonstrated longer stop-signal reaction times for incongruent trials than for congruent trials. This indicates interaction between stopping and the informational conflict. Here we suggest that "zooming in" on Task-control failure trials will reveal another interaction--between stopping and Task conflict. To examine this suggestion, we combined stop-signal and Stroop Tasks in the same experiment. When participants' control failed and erroneous responses to a stop signal occurred, a reverse facilitation emerged in the Stroop Task (Experiment 1) and this was eliminated using methods that manipulated the emergence of the reverse facilitation (Experiment 2). Results from both experiments were replicated when all stimuli were used in the same Task (Experiment 3). In erroneous response trials, only the Task conflict increased, not the informational conflict. These results indicate that Task conflict and stop-signal inhibition share a common control mechanism that is dissociable from the control mechanism activated by the informational conflict.
Jonathan D Cohen - One of the best experts on this subject based on the ideXlab platform.
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anterior cingulate gyrus dysfunction and selective attention deficits in schizophrenia 15o h2o pet study during single trial Stroop Task performance
American Journal of Psychiatry, 1997Co-Authors: Cameron S Carter, Mark A Mintun, Thomas E Nichols, Jonathan D CohenAbstract:OBJECTIVE: Attentional deficits are a prominent aspect of cognitive dysfunction in schizophrenia. The anterior cingulate gyrus is proposed to be an important component of frontal attentional control systems. Structural and functional abnormalities have been reported in this region in schizophrenia, but their relationship to attentional deficits is unknown. The authors investigated the function of the anterior cingulate gyrus and the related neural systems that are associated with selective attention in patients with schizophrenia. METHOD: While subjects performed multiple blocks of a single-trial Stroop Task, [15O]H2O positron emission tomography scans were obtained. Fourteen patients with schizophrenia were compared with 15 normal subjects matched for age, gender, and parental education. RESULTS: The patients with schizophrenia responded at the same rate but made more errors in color naming during the color-incongruent condition. Consistent with the authors' hypothesis, patients with schizophrenia showed...
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interference and facilitation effects during selective attention an h215o pet study of Stroop Task performance
NeuroImage, 1995Co-Authors: Cameron S Carter, Mark A Mintun, Jonathan D CohenAbstract:To investigate the functional anatomy of interference and facilitation during selective attention, we studied 15 normal subjects using the H215O positron emission tomography technique and a computer presented single-trial Stroop Task for cognitive activation. Increases in regional cerebral blood flow (rCBF) were observed in a network of structures that have been previously associated with selective attention, including the anterior cingulate gyrus, the frontal polar cortex, the inferior parietal lobule, and the thalamus, as well as the lingual gyrus. Furthermore rCBF decreases (compared to control states) were observed in lateral extra-striate cortex. rCBF changes in prefrontal and extra-striate regions varied with differences in the need to modulate the influence of word and color information while subjects responded to either incongruent or congruent Stroop stimuli. These results indicate the utility of Stroop procedures for investigating the functional anatomy of selective attention. Given recent interest regarding the role of the anterior cingulate gyrus in the pathophysiology of neuropsychiatric disorders, our results also suggest that the Stroop Task can serve as a reliable neurobehavioral probe for this region. The significance of these results for understanding processing mechanisms underlying selective attention is discussed within the framework of a parallel distributed processing model of Stroop Task performance.
Benjamin A. Parris - One of the best experts on this subject based on the ideXlab platform.
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assessing stimulus stimulus semantic conflict in the Stroop Task using saccadic two to one color response mapping and preresponse pupillary measures
Attention Perception & Psychophysics, 2015Co-Authors: Nabil Hasshim, Benjamin A. ParrisAbstract:Conflict in the Stroop Task is thought to come from various stages of processing, including semantics. Two-to-one response mappings, in which two response-set colors share a common response location, have been used to isolate stimulus–stimulus (semantic) from stimulus–response conflict in the Stroop Task. However, the use of congruent trials as a baseline means that the measured effects could be exaggerated by facilitation, and recent research using neutral, non-color-word trials as a baseline has supported this notion. In the present study, we sought to provide evidence for stimulus–stimulus conflict using an oculomotor Stroop Task and an early, preresponse pupillometric measure of effort. The results provided strong (Bayesian) evidence for no statistical difference between two-to-one response-mapping trials and neutral trials in both saccadic response latencies and preresponse pupillometric measures, supporting the notion that the difference between same-response and congruent trials indexes facilitation in congruent trials, and not stimulus–stimulus conflict, thus providing evidence against the presence of semantic conflict in the Stroop Task. We also demonstrated the utility of preresponse pupillometry in measuring Stroop interference, supporting the idea that pupillary effects are not simply a residue of making a response.
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application of the ex gaussian function to the effect of the word blindness suggestion on Stroop Task performance suggests no word blindness
Frontiers in Psychology, 2013Co-Authors: Benjamin A. Parris, Zoltan Dienes, Timothy L HodgsonAbstract:The aim of the present paper was to apply the ex-Gaussian function to data reported by Parris et al. (2012) given its utility in studies involving the Stroop Task. Parris et al. showed an effect of the word blindness suggestion when Response-Stimulus Interval (RSI) was 500ms but not when it was 3500ms. Analysis revealed that: 1) The effect of the suggestion on interference is observed in µ, supporting converging evidence indicating the suggestion operates over response competition mechanisms; and, 2) Contrary to Parris et al., an effect of the suggestion was observed in µ when RSI was 3500ms. The reanalysis of the data from Parris et al. (2012) supports the utility of ex-Gaussian analysis in revealing effects that might otherwise be thought of as absent. We suggest that word reading itself is not suppressed by the suggestion but instead that response conflict is dealt with more effectively.
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Oxytocin impedes the effect of the word blindness post-hypnotic suggestion on Stroop Task performance
Social cognitive and affective neuroscience, 2013Co-Authors: Benjamin A. Parris, Zoltan Dienes, Sarah Bate, Stace GothardAbstract:The ability to enhance sensitivity to relevant (post)hypnotic suggestions has implications for creating clinically informed analogues of psychological and neuropsychological conditions and for the use of hypnotic interventions in psychological and medical conditions. The aim of this study was to test the effect of oxytocin inhalation on a post-hypnotic suggestion that previously has been shown to improve the selectivity of attention in the Stroop Task. In a double-blind placebo-controlled between-subjects study, medium hypnotizable individuals performed the Stroop Task under normal conditions and when they had been given a post-hypnotic suggestion that they would perceive words as meaningless symbols. In line with previous research, Stroop interference was substantially reduced by the suggestion in the placebo condition. However, contrary to expectations, oxytocin impeded the effect of the word blindness suggestion on performance. The results are explained in terms of the requirement for the re-implementation of the word blindness suggestion on a trial-by-trial basis and the need to sustain activation of the suggestion between trials. The findings contrast with a recent study showing a beneficial effect of oxytocin on sensitivity to (post)hypnotic suggestions but are consistent with findings showing a detrimental effect of oxytocin on memory processes.
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temporal constraints of the post hypnotic word blindness suggestion on Stroop Task performance
2012Co-Authors: Benjamin A. Parris, Zoltan Dienes, Timothy L HodgsonAbstract:The present work investigated possible temporal constraints on the posthypnotic word blindness suggestion effect. In a completely within-subjects and counterbalanced design 19 highly suggestible individuals performed the Stroop Task both with and without a post-hypnotic suggestion that they would be unable to read the word dimension of the Stroop stimulus, both when response-stimulus interval (RSI) was short (500ms) or equivalent to previous studies (3500ms). The suggestion reduced Stroop interference in the short RSI condition (54ms vs. 6ms) but not in the long RSI condition (52ms vs. 56ms), and did not affect Stroop facilitation. Our results suggest that response to the suggestion involves reactive top-down control processes that persist only if levels of activation can be maintained.
Marty G. Woldorff - One of the best experts on this subject based on the ideXlab platform.
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cross modal stimulus conflict the behavioral effects of stimulus input timing in a visual auditory Stroop Task
PLOS ONE, 2013Co-Authors: Sarah E. Donohue, Lawrence G Appelbaum, Christina J Park, Kenneth C Roberts, Marty G. WoldorffAbstract:Cross-modal processing depends strongly on the compatibility between different sensory inputs, the relative timing of their arrival to brain processing components, and on how attention is allocated. In this behavioral study, we employed a cross-modal audio-visual Stroop Task in which we manipulated the within-trial stimulus-onset-asynchronies (SOAs) of the stimulus-component inputs, the grouping of the SOAs (blocked vs. random), the attended modality (auditory or visual), and the congruency of the Stroop color-word stimuli (congruent, incongruent, neutral) to assess how these factors interact within a multisensory context. One main result was that visual distractors produced larger incongruency effects on auditory targets than vice versa. Moreover, as revealed by both overall shorter response times (RTs) and relative shifts in the psychometric incongruency-effect functions, visual-information processing was faster and produced stronger and longer-lasting incongruency effects than did auditory. When attending to either modality, stimulus incongruency from the other modality interacted with SOA, yielding larger effects when the irrelevant distractor occurred prior to the attended target, but no interaction with SOA grouping. Finally, relative to neutral-stimuli, and across the wide range of the SOAs employed, congruency led to substantially more behavioral facilitation than did incongruency to interference, in contrast to findings that within-modality stimulus-compatibility effects tend to be more evenly split between facilitation and interference. In sum, the present findings reveal several key characteristics of how we process the stimulus compatibility of cross-modal sensory inputs, reflecting stimulus processing patterns that are critical for successfully navigating our complex multisensory world.
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Is conflict monitoring supramodal? Spatiotemporal dynamics of cognitive control processes in an auditory Stroop Task
Cognitive Affective & Behavioral Neuroscience, 2012Co-Authors: Sarah E. Donohue, Mario Liotti, Ricardo Perez, Marty G. WoldorffAbstract:The electrophysiological correlates of conflict processing and cognitive control have been well characterized for the visual modality in paradigms such as the Stroop Task. Much less is known about corresponding processes in the auditory modality. Here, electroencephalographic recordings of brain activity were measured during an auditory Stroop Task, using three different forms of behavioral response (overt verbal, covert verbal, and manual), that closely paralleled our previous visual Stroop study. As was expected, behavioral responses were slower and less accurate for incongruent than for congruent trials. Neurally, incongruent trials showed an enhanced fronto-central negative polarity wave (N_inc), similar to the N450 in visual Stroop Tasks, with similar variations as a function of behavioral response mode, but peaking ~150 ms earlier, followed by an enhanced positive posterior wave. In addition, sequential behavioral and neural effects were observed that supported the conflict-monitoring and cognitive adjustment hypothesis. Thus, while some aspects of the conflict detection processes, such as timing, may be modality dependent, the general mechanisms would appear to be supramodal.
Eyal Kalanthroff - One of the best experts on this subject based on the ideXlab platform.
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Task conflict and proactive control a computational theory of the Stroop Task
Psychological Review, 2017Co-Authors: Eyal Kalanthroff, Eddy J. Davelaar, Avishai Henik, Liat Goldfarb, Marius UsherAbstract:The Stroop Task is a central experimental paradigm used to probe cognitive control by measuring the ability of participants to selectively attend to Task-relevant information and inhibit automatic Task-irrelevant responses. Research has revealed variability in both experimental manipulations and individual differences. Here, we focus on a particular source of Stroop variability, the reverse-facilitation (RF; faster responses to nonword neutral stimuli than to congruent stimuli), which has recently been suggested as a signature of Task conflict. We first review the literature that shows RF variability in the Stroop Task, both with regard to experimental manipulations and to individual differences. We suggest that Task conflict variability can be understood as resulting from the degree of proactive control that subjects recruit in advance of the Stroop stimulus. When the proactive control is high, Task conflict does not arise (or is resolved very quickly), resulting in regular Stroop facilitation. When proactive control is low, Task conflict emerges, leading to a slow-down in congruent and incongruent (but not in neutral) trials and thus to Stroop RF. To support this suggestion, we present a computational model of the Stroop Task, which includes the resolution of Task conflict and its modulation by proactive control. Results show that our model (a) accounts for the variability in Stroop-RF reported in the experimental literature, and (b) solves a challenge to previous Stroop models-their ability to account for reaction time distributional properties. Finally, we discuss theoretical implications to Stroop measures and control deficits observed in some psychopathologies. (PsycINFO Database Record
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evidence for interaction between the stop signal and the Stroop Task conflict
Journal of Experimental Psychology: Human Perception and Performance, 2013Co-Authors: Eyal Kalanthroff, Liat Goldfarb, Avishai HenikAbstract:Performance of the Stroop Task reflects two conflicts--informational (between the incongruent word and ink color) and Task (between relevant color naming and irrelevant word reading). The Task conflict is usually not visible, and is only seen when Task control is damaged. Using the stop-signal paradigm, a few studies demonstrated longer stop-signal reaction times for incongruent trials than for congruent trials. This indicates interaction between stopping and the informational conflict. Here we suggest that "zooming in" on Task-control failure trials will reveal another interaction--between stopping and Task conflict. To examine this suggestion, we combined stop-signal and Stroop Tasks in the same experiment. When participants' control failed and erroneous responses to a stop signal occurred, a reverse facilitation emerged in the Stroop Task (Experiment 1) and this was eliminated using methods that manipulated the emergence of the reverse facilitation (Experiment 2). Results from both experiments were replicated when all stimuli were used in the same Task (Experiment 3). In erroneous response trials, only the Task conflict increased, not the informational conflict. These results indicate that Task conflict and stop-signal inhibition share a common control mechanism that is dissociable from the control mechanism activated by the informational conflict.
