Reverse Stroop Task Research Articles

Upper-left gaze bias reveals competing search strategies in a reverse Stroop task

Three experiments with a total of 87 human observers revealed an upper-left spatial bias in the initial movement of gaze during visual search. The bias was present whether or not the explicit control of gaze was required for the task. This bias may be part of a search strategy that competed with the fixed-gaze parallel search strategy hypothesized by Durgin [Durgin, F. H. (2003). Translation and competition among internal representations in a reverse Stroop effect. Perception &Psychophysics, 65, 367–378.] for this task. When the spatial probabilities of the search target were manipulated either in accord with or in opposition to the existing upper-left bias, two orthogonal factors of interference in the latency data were differentially affected. The two factors corresponded to two different forms of representation and search. Target probabilities consistent with the gaze bias encouraged opportunistic serial search (including gaze shifts), while symmetrically opposing target probabilities produced latency patterns more consistent with parallel search based on a sensory code.

Transitions between color categories mapped with a reverse Stroop task

In the reverse Stroop task, observers are instructed to ignore the ink color in which a color word is printed (the distractor color) and to respond to the meaning of the color word (the target). Reaction times (RTs) are faster with congruent combinations when the ink color matches the word than with incongruent combinations when the ink color does not match the word. We manipulated the distracting ink color from congruent to incongruent and measured the transition from facilitation to interference. In Experiment 1, we confirmed that this transition could be assessed independently from the contextual influence of particular sets of stimuli and responses, implying that the color space in which interference and facilitation occurs is generalizable. In Experiment 2, we obtained reverse Stroop data for transitions between red and yellow, yellow and green, green and blue, and blue and red, and compared them with independent estimates of color appearance obtained by hue scaling for the same chromaticity samples. We find that the magnitude of the reverse Stroop effect can provide a reliable index of the similarity of color appearance between the distracting chromaticity and the color category represented by the target color word. Moreover, it will allow us to quantify the mapping between the chromaticity space defined at the cone photoreceptors and a cognitive color space defined at an advanced level of neural processing.

Stroop performance in pathological gamblers

Pathological gambling is a relatively prevalent psychiatric disorder that typically leads to severe family, social, legal, and occupational problems and is associated with a high rate of suicide attempts. Understanding the neurobiological basis of pathological gambling is a current focus of research, and emerging data have demonstrated that pathological gamblers may have impaired decision-making because of an inability to inhibit irrelevant information. In this study, we examined pathological gamblers by using the Stroop Color-Word Test, a neurocognitive task used to assess interference control. The “reverse” variant of the Stroop Color-Word Test was administered to a cohort of medication-free pathological gamblers (n=62) and a cohort of age-matched controls (n=83). In the reverse variant of the Stroop task, subjects are asked to read the meaning of the word rather than name the ink color. The reverse Stroop task was chosen because it highly discriminates ability to inhibit interference in a population of psychiatric patients. In our study, performance on the reverse Stroop task in the pathological gamblers was significantly slower and less accurate than in the healthy subjects. A new finding in our study was that for pathological gamblers, the average reaction time in the neutral condition (where the color names are displayed in black letters) was slower than the average reaction time in the incongruent condition (where the meaning of the color name and the color of the printed letters are different). This controlled study extends previous findings by showing that performance on the Stroop task is impaired in a sample of medication-free pathological gamblers.

Reverse stroop effects with untranslated responses.

Translation accounts have argued that the presence of a Stroop effect in the context of a nonvocal untranslated response is caused by verbal mediation. In its simplest form, color-labeled buttons are translated into a verbal code that interferes with color responses. On this logic, in the reverse Stroop task (identify the word; ignore the color), responses made via word-labeled buttons should also be verbally mediated. Thus, no reverse Stroop effect (RSE) should be seen. The authors tested this verbal mediation hypothesis in 4 reverse Stroop task experiments. An RSE was observed across 4 experiments. The results of Experiments 3 and 4 suggest that this RSE is driven by response competition. It is argued that the data from these 4 experiments are inconsistent with unadorned translation accounts of the RSE but consistent with an account in which the strength of association between a stimulus and a specific response plays a major role.

逆ストループ課題における半球間干渉の非対称性

The purpose of the present study was to examine the effect of interference on interhemispheric interaction in the reverse-stroop task. In two experiments, color-word in black ink and color-patch in red or blue ink were briefly presented to a bilateral visual-field (BVF). The participants were asked to identify the color word, ignoring the color patch. In Experiment 1, color-words written in kanji character were used as target ([Chinese character: see test] or [Chinese character: see test]). In Experiment 2, color-words written in kana character were used as target ([Chinese characters: see test] or [Chinese characters: see test]). The result in Experiment I showed that the size of the interference effect was invariant irrespective of the visual-field of the target. On the contrary, in Experiment 2, the interference effect was larger in the condition where the kana color-word was presented to left visual-field (LVF) than to right visual-field (RVF). These results suggested that the interference effect would be modulated by the dominant hemisphere for processing the target.

Evidencing inhibitory deficits in Alzheimer’s disease through interference effects and shifting disabilities in the Stroop test

To investigate the contribution of inhibitory deficits in the deterioration of executive function abilities in Alzheimer’s disease (AD), a modified version of the Stroop test was submitted to 44 AD patients and 44 elderly controls. Half of the subjects performed successively the Interference Stroop task, the two control tasks and the Reverse Stroop task, and half performed the Reverse Stroop task, the control tasks and finally the Interference Stroop task. This experimental design allowed to assess inhibitory deficits by measuring classical interference effects but also by measuring the ability to shift between tasks instructions. Results confirmed AD patients’ difficulty in suppressing the automatic response of reading in the Interference Stroop task. Moreover, AD patients presented worsened performances in the Interference task when administered after the Reverse task, and a Reverse Stroop effect was found in the patients revealing their difficulty in suppressing a previously relevant rule in order to learn a new one.

Event-related potentials to Stroop and reverse Stroop stimuli

In the Stroop task, the latency of response to a colour is either faster or slower in the presence of a congruent or incongruent colour–word (J. Exp. Psychol. 18 (1935) 643). Debate remains as to whether this effect occurs during early stimulus processing or late response competition. The present study examined the task using reaction time (RT) and event-related potentials to determine temporal differences in this processing. The ‘reverse Stroop’ effect (where colour interferes with processing of a colour–word) which is much less well established, was also examined. Standard Stroop interference was found as well as reverse Stroop interference. A late lateralised negativity at frontal sites was greater for Incongruent trials and also for the word–response (reverse Stroop) task, and was interpreted as semantic selection and word-rechecking effects. Late positive component latency effects generally mirrored the speed of processing of the different conditions found in RT data. Stroop effects were also found in early temporal N100 and parietal P100 components, which differentiated Congruent from Incongruent trials in the reverse Stroop but not the standard Stroop, and were interpreted as early perception of physical mismatch between the colour and word. It was concluded that Stroop stimuli are processed in parallel in a network of brain areas rather than a particular structure and that Stroop interference arises at the output stage.

Refereed Papers

To investigate the contribution of inhibitory deficits in the deterioration of executive function abilities in Alzheimer’s disease (AD), a modified version of the Stroop test was submitted to 44 AD patients and 44 elderly controls. Half of the subjects performed successively the Interference Stroop task, the two control tasks and the Reverse Stroop task, and half performed the Reverse Stroop task, the control tasks and finally the Interference Stroop task. This experimental design allowed to assess inhibitory deficits by measuring classical interference effects but also by measuring the ability to shift between tasks instructions. Results confirmed AD patients’ difficulty in suppressing the automatic response of reading in the Interference Stroop task. Moreover, AD patients presented worsened performances in the Interference task when administered after the Reverse task, and a Reverse Stroop effect was found in the patients revealing their difficulty in suppressing a previously relevant rule in order to learn a new one.

Interference effects in the Stroop and Simon paradigms.

The possibility that Stroop and Simon effects reflect the same cognitive processes was tested in 3 experiments with 62 adult Ss. The words LEFT and RIGHT were shown left and right of screen center. Similar levels of interference were found for a Simon task (keypress to meaning of word) and a spatial Stroop task (name its location). A reverse Simon task (keypress to word location) showed minimal interference from the irrelevant word, but in a reverse spatial Stroop task (read the word aloud) interference from the irrelevant location was sizable. This poses difficulty for translational accounts of Stroop interference. Presenting LEFT and RIGHT laterally balanced by a color-name foil yielded a Simon effect inconsistent with an orienting response hypothesis. With bilateral stimuli in a reverse Simon task, interference was marked, supporting an integrative account of Stroop and Simon effects in terms of cognitive activation and the salience of irrelevant stimuli.

集団用ストループ・逆ストループテスト

We produced the group version of Stroop and reverse-Stroop color and word test through the use of a matching method. The test consisted of two control tasks, one Stroop task and a reverse-Stroop task. In four experiments we examined the validity and reliability of the test as follows. Experiment 1 showed the significant amount of Stroop interference similar to traditional oral naming method Experiments 2, 3, 4 showed neither order effect of tasks nor practice effect in the Stroop and the reverse-Stroop tasks, together with the high test-retest reliability (r=.695-824), respectively. It is believed that this test might be a valuable tool to the researcher as a measure of individual difference in human information processing.