Suggestion does not de-automatize word reading: Evidence from the semantically based Stroop task

Recent studies have shown that the suggestion for participants to construe words as meaningless symbols reduces, or even eliminates, standard Stroop interference in highly suggestible individuals (Raz, Fan, & Posner, 2005; Raz, Kirsch, Pollard, & Nitkin-Kaner, 2006). In these studies, the researchers consequently concluded that this suggestion de-automatizes word reading. The aim of the present study was to closely examine this claim. To this end, highly suggestible individuals completed both standard and semantically based Stroop tasks, either with or without a suggestion to construe the words as meaningless symbols (manipulated in both a between-participants [Exp. 1] and a within-participants [Exp. 2] design). By showing that suggestion substantially reduced standard Stroop interference, these two experiments replicated Raz et al.'s (2006) results. However, in both experiments we also found significant semantically based Stroop effects of similar magnitudes in all suggestion conditions. Taken together, these results indicate that the suggestion to construe words as meaningless symbols does not eliminate, or even reduce, semantic activation (assessed by the semantically based Stroop effect) in highly suggestible individuals, and that such an intervention most likely reduces nonsemantic task-relevant response competition related to the standard Stroop task. In sum, contrary to Raz et al.'s claim, suggestion does not de-automatize or prevent reading (as shown by a significant amount of semantic processing), but rather seems to influence response competition. These results also add to the growing body of evidence showing that semantic activation in the Stroop task is indeed automatic.     

Inhibitory control and affective valence processing in dementia of the alzheimer type

Emotional and traditional Stroop effects were contrasted in individuals with Alzheimer's disease (AD) and age‐equated, non‐demented individuals to examine (a) differences in the speed of processing emotional versus neutral words; and (b) the extent to which the emotional valence influences interference effects. Individuals with moderate AD experienced larger traditional Stroop interference effects than did healthy elderly or individuals with mild AD. Emotional Stroop effects were evident among individuals with moderate AD and significantly greater than elderly and individuals with mild AD who exhibited minimal effects. For negative words, significant differences were only observed between individuals with moderate AD and healthy elderly. Emotional Stroop effects among individuals with AD were not statistically different for positive and negative words. The impact of stimulus intensity level and AD‐associated changes to the prefrontal cortex and amygdala on emotional Stroop effects requires further investigation.     

Suggestion overrides the Stroop effect in highly hypnotizable individuals

Cognitive scientists distinguish between automatic and controlled mental processes. Automatic processes are either innately involuntary or become automatized through extensive practice. For example, reading words is a purportedly automatic process for proficient readers and the Stroop effect is consequently considered the "gold standard" of automated performance. Although the question of whether it is possible to regain control over an automatic process is mostly unasked, we provide compelling data showing that posthypnotic suggestion reduced and even removed Stroop interference in highly hypnotizable individuals. Drawing on a large sample of highly hypnotizable participants, we examined the effects of suggestion on Stroop performance both with and without a posthypnotic suggestion to perceive the input stream as meaningless symbols. We show that suggestion administered to highly hypnotizable persons significantly reduced Stroop interference and derailed a seemingly automatic process.     

Suggestion reduces the stroop effect

We examined the effects of suggestion on Stroop interference in highly suggestible individuals. Participants completed the Stroop task with and without a suggestion to perceive Stroop words as meaningless symbols. Half the participants were given this suggestion in hypnosis, and half were given the suggestion without the induction of hypnosis. Suggestion produced a significant reduction in Stroop inhibition, accounting for about 45% of the variance in Stroop responding, regardless of whether hypnosis had been induced. These findings indicate that suggestion can at least partially overcome the automaticity associated with the Stroop effect.     

A slow component of classic Stroop interference

The interference in colour naming may extend beyond critical Stroop trials. This “slow” effect was first discovered in emotional Stroop tasks, but is extended here to classical Stroop. In two experiments, meaningless coloured letter strings followed a colour word or neutral word. Student participants (Experiment 1), and 18 stroke patients and 18 matched controls (Experiment 2) showed substantial interference by incongruent colour words, both in the word trial (fast component) and in the subsequent string trial (slow component). Different patient subgroups emerged from the comparison of Stroop performance with the controls. An association of fast and slow components was only found in one subgroup. Exploratory analyses revealed no clear differences in damage location between subgroups. Fast interference caused by colour-meaning conflict may be specific for classical Stroop, but the broader occurrence of slow effects suggests a more generalised process of disengagement from attention-demanding stimuli.     

Stroop effects for masked threat words: Pre‐attentive bias or selective awareness?

The single‐trial emotional Stroop effect for masked threat words, and its association with anxiety, anger, and depression was studied in a group of men (n = 24) and women (n = 24) while controlling for possible differential thresholds for threat words versus neutral words. Stroop interference for masked threat words was found to correlate with trait anxiety, and the effect could not be explained by any differences in thresholds due to valence, neither at a subjective (conscious identification task) nor at an objective (lexical decision task) level of awareness. Jacoby's exclusion task was explored as an alternative measure of conscious awareness, and the results corroborated the conclusion that the Stroop effect for masked threat words was the result of preattentive processes. Unexpectedly, however, the correlation between Stroop interference for masked threat words and trait anxiety was found only among the men.     

Colour-identification of differentially valenced words in anxiety

Abstract

Two groups of individuals, one high in trait anxiety and the other low in trait anxiety, performed a Stroop task in which threat, neutral, and pleasant words were presented. The results indicated clear differences between the high- and low-trait groups in their performance on this task. The low-trait group's performance was similar for all three types of sitmuli, whereas the high-trait group's responses were fastest for pleasant stimuli and slowest for threat-related stimuli. A recognition task to examine incidental learning of the “irrelevant” Stroop words showed that whilst the high-trait group had a stronger tendency to respond positively to all trials (critical and distractor) than the low-trait group, there were no differences in sensitivity between the two groups.     

Cognitive processing of personally relevant information

Abstract

Subjects performed an idiographic, computerised version of the modified Stroop colour-naming task after having undergone a film-induced mood manipulation designed to produce either anxiety, elation, or a neutral mood. The Stroop stimuli were words related either to the subject's positive current concerns (e.g. goals, interests), to the subject's negative current concerns (e.g. personal worries), or to neither. The results indicated that words strongly related to subject's positive as well as to negative current concerns produced significantly more Stroop interference than did words unrelated or weakly related to their current concerns. Although the films strongly influenced the subjects' moods in predicted directions initially, mood changes were largely not maintained throughout the experiment. Thus, it is not surprising that no significant interactions with word type were found. These results indicate that the “emotional Stroop effect” occurs in normal subjects as well as in anxious patients, and occurs with positive as well as with negative material of strong personal relevance.     

Stroop interference, self-focus and perfectionism in social phobics

Stroop interference was studied in a group of social phobics under two conditions: presence or absence of a mirror. The mirror was used with the purpose of inducing a higher level of self-focus during testing; this was expected to activate dysfunctional self structures that would increase Stroop interference on socially threatening words. The social phobics showed a Stroop interference effect on socially threatening words, but not on physically threatening words or colour words, relative to the control group. The hypothesis that the presence of the mirror would increase the Stroop interference on socially threatening words, however, was not supported by the data. On the other hand, the social phobics scored significantly higher than the controls on trait measures of self-consciousness and perfectionism. There was a correlation between perfectionism (concern over mistakes) and Stroop interference on socially threatening words. Self-consciousness also correlated with Stroop interference, but this effect was unexpectedly seen most clearly on physically threatening words.     

The intention interference effect and aging: similar magnitude of effects for young and old adults

In young adults, intentions have been shown to be more accessible (e.g. faster reaction times and higher accuracy) compared to other sorts of to‐be‐remembered information, a result termed an ‘intention superiority effect’ (Goschke & Kuhl, 1993 ). In the current study, we assessed whether older adults also demonstrate this superiority of intention‐related material and we used a new interference paradigm to examine performance. On each trial, participants performed a Stroop‐like colour‐naming task on a short series of words, including words related to an intention that they encoded at the beginning of the trial. In Experiment 1, results revealed an ‘intention interference effect’ for both young and older adults in which performance was slower for words belonging to an intention that participants intended to carry out versus an intention that did not have to be executed. In Experiment 2, we tested the effect that completing an intention had on the representation of intentions. For both groups, completing an intention led to a decrease in interference in Stroop task performance. Copyright © 2005 John Wiley & Sons, Ltd.     

Generalizability of carry-over effects in the emotional Stroop task

The emotional Stroop task has been the most widely used task to examine attentional bias to emotionally salient stimuli. In one format of this task, words are presented to participants in a mixed randomized or quasi-randomized sequence. Using a mixed smoking Stroop task, we have previously demonstrated that smokers are slower to respond to words which follow smoking-related words than words which follow neutral words. Here we show that this carry-over effect is present in heroin addicts-but not control subjects-in a heroin Stroop task, and in normal subjects in a stress Stroop task. Thus, the effect generalizes to other populations. In addition, an examination of the studies that have collected data from both mixed and blocked formats provides converging evidence for the presence of carry-over effects. We discuss the implications of the carry-over effect for research using the emotional Stroop task.     

焦虑个体“冷”、“热”执行功能Stroop效应量比较

该文采用Stroop实验范式对筛选出的49名高焦虑个体和48名低焦虑个体的“冷”、“热”执行功能进行测量,以探讨不同焦虑程度个体“冷”、“热”执行功能间的差异。结果表明,在“冷”执行功能方面,高焦虑个体与低焦虑个体Stroop效应量之间没有显著差异;在“热”执行功能方面,两组被试情绪Stroop的效应量无差异;两类词;12的Stroop效应量差异显著;词汇类型×被试类型的交互作用非常显著;进一步的简单效应分析表明,两组被试的情绪Stroop效应量在消极词汇水平差异显著,两类词汇Stroop效应量在低焦虑组差异显著。说明高、低焦虑个体在“冷”执行功能上没有显著差异,高焦虑个体的“冷”执行功能正常,而“热”执行功能下降,表现为高焦虑个体对两极情绪的趋避关系失调,即对消极情绪具有偏向性,对积极情绪具有回避性。     

Preattentive bias for snake words in snake phobia?

Stroop interference and skin conductance responses (SCRs) for words related to snakes, spiders, flowers, and mushrooms were studied in a group of women (n=40) with snake phobia who were randomised to a stress or no-stress condition. The 21 low-stress snake phobics showed Stroop interference for unmasked (but not for masked) snake words, compared with 21 age- and sex-matched controls. Stroop interference was not significantly different between high-stress and low-stress snake phobics. No support for stronger SCRs for masked snake words was found in snake phobics in a lexical decision task with masked presentations of the same words. The lack of a masked Stroop interference in snake phobics suggests a possible difference in cognitive-emotional mechanisms underlying specific phobia vs. other anxiety disorders that deserves further investigation.     

初中生学习成绩与成就STROOP干扰

取某普通中学初中学生129人,使用修正的Stroop任务,测试被试对积极关联词语、消极关联词语和中性词语的颜色命名的反应时间,结果发现,初中学生对成就关联词语的反应时间比中性词语长,特别是在消极关联词语方面,差异显著,表现出了典型的Stroop干扰;学习好的同学在所有词语方面的反应时间都比学习成绩差的同学反应时间长,特别是在成就关联词语方面,差异极显著,学习好的同学表现出了更加明显的Stroop干扰.学习成绩与成就关联词语的反应时间有显著的相关.女同学对所有词语的反应时间都比男同学时间长,特别是在高成就反应时间上,二者差异显著,女同学比男同学有更加明显的成就Stroop干扰.     

Using the Personal Stroop to Detect Children's Awareness of Social Rejection by Peers

A personal (or emotional) Stroop methodology was used to assess children's internalisation of peer rejection. A computerised Stroop colour-naming task with a voice-activated timer was given to 59 socially popular and unpopular elementary schoolchildren. We presented negative social words and three sets of control words (positive social, negative nonsocial, and positive nonsocial) individually and in random order. Unpopular children (but not popular children) demonstrated significantly greater colour-naming interference on negative social words versus control words, suggesting that they had internalised personally relevant social status information. This sensitivity to negative social content words remained even after controlling for grade level, self-reported depressive symptoms, and self-reported social competence. Advantages and disadvantages of the personal Stroop methodology relative to self-report methodologies are discussed.     

Stroop interference effects in partially colored Stroop words

In the Stroop task word reading is thought to be automatic since it runs without intentional monitoring and is difficult to avoid. This view has recently been challenged by observations that Stroop interference is reduced when only part of the Stroop word is colored. In this study we asked whether the extent of Stroop interference varies with the position of the colored letter(s). We observed that Stroop interference was smallest when the first letter(s) were colored and largest when either the last letter(s) or whole word were colored. On these findings we suggest that colored and noncolored parts of partially colored words are processed separately and differently, and that selection of the color dimension for explicit report entails inhibition of the to-be-ignored colored letters.     

Effects of Emotional Experience for Abstract Words in the Stroop Task

In this study, we examined the effects of emotional experience, a relatively new dimension of emotional knowledge that gauges the ease with which words evoke emotional experience, on abstract word processing in the Stroop task. In order to test the context‐dependency of these effects, we accentuated the saliency of this dimension in Experiment 1A by blocking the stimuli such that one block consisted of the stimuli with the highest emotional experience ratings and the other block consisted of the stimuli with the lowest emotional experience ratings. We attenuated the saliency of this dimension in Experiment 1B by intermixing the stimuli. We observed slower color naming performance for words with higher emotional experience ratings only in Experiment 1A, suggesting that the dimension of emotional experience is an aspect of semantic representation for abstract words but that its influence can be modulated by context. We interpret these results more generally using Vigliocco, Meteyard, Andrews, and Kousta's (2009) framework of semantic representation, and more specifically using Cohen, Dunbar, and McClelland's (1990) model of Stroop task performance.     

Cognitive bias,emotion, and somatic complaints in a normal sample

Cognitive bias (Stroop interference and implicit memory bias) for masked and unmasked threat words (illness words and negative emotion words) was investigated for its associations with emotion (anxiety, anger/aggression, and positive affect) and somatic complaints in a randomly selected community sample of 138 individuals. Because measures of cognitive bias are inherently bipolar, the data were tested for both linear and curvilinear trends. Cross-sectional analysis showed that the associations between somatic anxiety and Stroop interference for unmasked threat words were better described in terms of curvilinear than linear models, and that degree of somatic complaints was associated with Stroop facilitation for masked threat words. Longitudinal analysis showed that Stroop interference for masked threat words predicted lack of positive affect during an ensuing eight weeks daily recording period. Implicit memory bias was found to be negatively associated with measures of anger/aggression, both in the cross-sectional and longitudinal analyses. We suggest that: (a) cognitive bias should be treated as a bipolar construct in future research; (b) the phenomenon of Stroop facilitation for threat words deserves further exploration; and (c) more research should address the question about the relationship between cognitive bias and other emotions than anxiety (e.g., positive affect and anger).     

Adults' versus children's performance on the Stroop task: Interference and facilitation

Stroop tasks (Stroop, 1935) present stimuli having two dimensions, and participants respond to one dimension whilst ignoring the other. The two dimensions are made congruent, incongruent or neutral with respect to one another. Many claim that ‘Stroop interference’ is higher in children than in adults. However, taking interference as the difference between the incongruent condition and the neutral condition, with interference within the congruent condition itself termed the ‘incongruity effect’ then surprisingly few studies directly address this issue. Also, there is recent debate as to whether the ‘facilitation effect’ (the contrast between the congruent and neutral conditions) is just the opposite of interference. The present investigation (N = 31) concerned a direct comparison between children and adults. Although the incongruity effect reduced with age, interference did not. However, facilitation was far higher in children than in adults. The groups' opposite facilitation/interference asymmetry was used to examine the recent claim that these derive from inadvertent word‐reading and suppression of semantic activation, respectively; rather than solely from the latter.     

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.