Cognitive Bias Via the Internet: A Comparison of Web‐Based and Standard Emotional Stroop Tasks in Social Phobia

There is accumulating evidence to suggest that social phobia is associated with attentional bias for words related to social threat. Information processing in individuals with social phobia (n = 87) was investigated in the present study using 2 versions of the emotional Stroop task. Results from a standard emotional Stroop task indicated delayed colour naming of socially threatening words relative to neutral words, in line with previous research, whereas results from a Web‐based emotional Stroop task indicated a facilitation effect, with faster manual indication of colour choice for socially threatening words than for neutral words. Possible explanations for these contrasting findings and issues for further research are discussed.     

Cognitive bias via the Internet: a comparison of Web-based and standard emotional Stroop tasks in social phobia

There is accumulating evidence to suggest that social phobia is associated with attentional bias for words related to social threat. Information processing in individuals with social phobia (n = 87) was investigated in the present study using 2 versions of the emotional Stroop task. Results from a standard emotional Stroop task indicated delayed colour naming of socially threatening words relative to neutral words, in line with previous research, whereas results from a Web-based emotional Stroop task indicated a facilitation effect, with faster manual indication of colour choice for socially threatening words than for neutral words. Possible explanations for these contrasting findings and issues for further research are discussed.     

The colour naming of socially threatening words

An emotional Stroop task was used to investigate colour naming of socially threatening words in individuals who possess a repressive coping style. The Marlowe-Crowne scale (MC) and the Bendig version of the Taylor Manifest Anxiety Scale (MAS) were used to select repressor and control subjects, who subsequently completed the Stroop task. Repressors (high MC, low MAS) did not show an emotional Stroop effect, whereas low anxious (low MC, low MAS), high anxious (low MC, high MAS) and defensive high anxious (high MC, high MAS) all exhibited retarded colour naming of emotional words compared with neutral words. These results are discussed in terms of previous research in this area.     

Selective attention for masked and unmasked emotionally toned stimuli: Effects of trait anxiety,state anxiety,and test order

We investigated selective attention for masked and unmasked, threat, and positively valenced words, in high trait anxious (HTA) and low trait anxious (LTA) individuals using the emotional Stroop colour‐naming task. State anxiety was varied within participants through the threat of electric shock. To investigate whether the sequencing of the state anxiety manipulation affected colour‐naming latencies, the ordering of the shock threat and shock safe conditions was counterbalanced across participants. The results indicated that the ordering of the state anxiety manipulation moderated masked and unmasked threat bias effects. Specifically, relative to LTA individuals, HTA individuals showed a threat interference effect, but this effect was limited to those who performed under the threat of shock in the later stages of the experiment. Irrespective of exposure mode and state anxiety status, all individuals showed interference for threat in the early stages of the experiment, relative to a threat facilitation effect in the later stages of the experiment. For the unmasked trials alone, the data also revealed a significant threat interference effect for the HTA group relative to the LTA group in the shock threat condition, and this effect was evident irrespective of shock threat order. The results are discussed with respect to the automatic nature of emotional processing in anxiety.     

Does anxiety lead to selective processing of threat-related information?

Four experiments investigating the detailed nature of the attentional bias in anxiety are reported. Previous research using the Stroop task has shown that, when compared with non-patient controls, anxious patients are relatively slower at colour naming threat-related words than non-threat words. Experiments One and Two investigated whether this apparent attentional bias is a function of anxiety per se and/or is related to patient/non-patient status. Experiment One compared colour-naming times for threat and non-threat words in low, medium and high trait anxiety normal subjects. High anxiety was not associated with slower colour-naming times for threat words. Experiment Two compared generalized anxiety disorder patients with equally anxious non-patients and found that the patients were significantly slower at colour-naming threat words. Read aloud and dwell tasks were also included in these experiments in order to identify the mechanism of Stroop interference. Experiments Three and Four investigated whether anxious patients' attentional bias is specific to threat-related material or also extends to certain positive, emotional material. In Experiment Three words used in previous Stroop studies were rated for emotionality. Threat words were more emotional, as well as more threatening, than control words, indicating that previous studies have confounded threat and emotionality. Experiment Four compared colour-naming times for threat words, equally emotional positive words, and neutral words. Consistent with the emotionality hypothesis, generalized anxiety disorder patients were slower than non-anxious controls at colour naming both threat words and positive words. The theoretical, methodological and clinical implications of these results are discussed.     

Emotional Stroop via Internet among individuals with eating disorders

The present study investigated whether Stroop interference in eating disordered individuals for food - and body-related words, as repeatedly found previously using standard emotional Stroop tasks, would also be demonstrated when using an Internet based emotional Stroop task. Participants were anorexic women (n= 13), bulimic women (n= 20), non-clinically eating disordered women nevertheless over-concerned about eating and body appearance (n= 27) and normal control women (n= 31). Bulimic individuals showed Stroop interference for body-related words whereas anorexic individuals showed Stroop interference for food-related words. The present results thus suggest that administration of the emotional Stroop task is possible via the Internet. Furthermore, it is possible that the time consuming response delivery, relative to previous studies, could lead to Stroop interference only for the most emotionally significant information, in turn, differentiating between the core concerns of anorexic and bulimic individuals.     

Enduring cognitive dysfunction in unipolar major depression: A test–retest study using the Stroop paradigm

Hammar, Å., Sørensen, L., Årdal, G., Oedegaard, K.J., Kroken, R., Roness, A. & Lund, A. (2009). Enduring cognitive dysfunction in unipolar major depression: A test–retest study using the Stroop‐paradigm. Scandinavian Journal of Psychology. The aim of the study was to investigate automatic and effortful information processing with the Stroop paradigm in a long term perspective in patients with major depressive disorder (MDD). Patients were tested at two test occasions: at inclusion with a Hamilton Depression Rating Scale (HDRS) score >18, and after 6 months, when most patients had experienced symptom reduction. The Stroop paradigm is considered to measure aspects of attention and executive functioning and consists of three conditions/cards: naming the color of the patches (Color), reading of the color‐words (Word) and naming the ink color of color‐words (Color‐Word). The Color‐Word condition is proved to be the most cognitive demanding task and requires the proband to actively suppress interference and is therefore considered to require more effortful information processing, whereas naming the color of the patches and reading the color‐words are expected to be more automatic and less cognitive demanding. A homogenous group of 19 patients with unipolar recurrent MDD according to DSM‐IV and a HDRS score of >18 were included in the study. A control group was individually matched for age, gender and level of education. Depressed patients performed equal to the control group on the Color and Word cards at both test occasions. However, the patients were impaired compared with the control group on the Color‐Word card task at both test occasions. Thus, the depressed patients showed no improvement of effortful attention/executive performance as a function of symptom reduction. The results indicate that the depressed patients showed impaired cognitive performance on cognitive demanding tasks when symptomatic and that this impairment prevailed after 6 months, despite significant improvement in their depressive symptoms.     

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.     

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。     

The lateralized emotional stroop task: left visual field interference in women

In a visual hemifield emotional Stroop task, 54 women were asked to name the color of laterally flashed emotional and neutral words while ignoring their semantic content. Vocal reaction times for color naming were recorded. The participants exhibited significant emotional interference effects in the left visual field, which tended to be larger for negative words than for positive words. Participants with higher trait anxiety scores exhibited larger interference for positive words in the left relative to the right visual field. The outcome indicates that, in women, emotional Stroop interference arises in the right rather than in the left hemisphere, with a larger impact of negative than of positive words, and with trait anxiety modulating the lateralized interference for positive words.     

A rational look at the emotional stroop phenomenon: a generic slowdown, not a stroop effect

The role of Stroop processes in the emotional Stroop effect was subjected to a conceptual scrutiny augmented by a series of experiments entailing reading or lexical decision as well as color naming. The analysis showed that the Stroop effect is not defined in the emotional Stroop task. The experiments showed that reading, lexical decision, and color naming all are slower with emotional words and that this delay is immune to task-irrelevant variation and to changes in the relative salience of the words and the colors. The delay was absent when emotional and neutral words appeared in a single block. A threat-driven generic slowdown is implicated, not a selective attention mechanism associated with the classic Stroop effect.     

The effect of orthographic and emotional neighbourhood in a colour categorization task

This study investigated whether and how the strength of reading interference in a colour categorization task can be influenced by lexical competition and the emotional characteristics of words not directly presented. Previous findings showed inhibitory effects of high-frequency orthographic and emotional neighbourhood in the lexical decision task. Here, we examined the effect of orthographic neighbour frequency according to the emotional valence of the higher-frequency neighbour in an emotional orthographic Stroop paradigm. Stimuli were coloured neutral words that had either (1) no orthographic neighbour (e.g. PISTIL [pistil]), (2) one neutral higher-frequency neighbour (e.g. tirade [tirade]/TIRAGE [draw]) or (3) one negative higher-frequency neighbour (e.g. idiome [idiom]/IDIOTE [idiotic]). The results showed that colour categorization times were longer for words with no orthographic neighbour than for words with one neutral neighbour of higher frequency and even longer when the higher-frequency neighbour was neutral rather than negative. Thus, it appears not only that the orthographic neighbourhood of the coloured stimulus words intervenes in a colour categorization task, but also that the emotional content of the neighbour contributes to response times. These findings are discussed in terms of lexical competition between the stimulus word and non-presented orthographic neighbours, which in turn would modify the strength of reading interference on colour categorization times.     

Mood-congruent free recall bias in anxious individuals is not a consequence of response bias

The status of mood-congruent free recall bias in anxious individuals was evaluated following incidental encoding of target words. Individuals with high and low levels of trait anxiety completed a modified Stroop task, which revealed an attentional bias for threat-related stimuli in anxious individuals. This group was significantly slower in naming the colour in which threat-related words were displayed compared to neutral words. In a subsequent free recall test for the words used in the modified Stroop task, anxious individuals recalled more threat-related words compared to low-anxious people. This difference was significant even when controlling for the false recall of items that had not been presented during study. These results support the view put forward by Russo, Fox, Bellinger, and Nguyen-Van-Tam (2001) that mood-congruent free recall bias in anxious individuals can be observed if the target material is encoded at a relatively shallow level. Moreover, contrary to Dowens and Calvo (2003), the current results show that the memory advantage for threat-related information in anxious individuals is not a consequence of response bias.     

情绪Stroop效应与Stroop效应的关系

摘 要 本研究通过位置判断任务、图-词干扰任务和色-词干扰任务来测量Stroop效应;通过表情面孔性别判断任务、情绪词汇判定任务和情绪图片颜色命名任务来测量情绪Stroop效应;运用结构方程建模的方法对情绪Stroop效应与Stroop效应的关系进行了探讨。结果发现：（1）Stroop效应和情绪Stroop效应是显著的。（2）情绪Stroop效应与Stroop效应是两种相互独立的现象。     

Mood-congruent free recall bias in anxious individuals is not a consequence of response bias

The status of mood-congruent free recall bias in anxious individuals was evaluated following incidental encoding of target words. Individuals with high and low levels of trait anxiety completed a modified Stroop task, which revealed an attentional bias for threat-related stimuli in anxious individuals. This group was significantly slower in naming the colour in which threat-related words were displayed compared to neutral words. In a subsequent free recall test for the words used in the modified Stroop task, anxious individuals recalled more threat-related words compared to low-anxious people. This difference was significant even when controlling for the false recall of items that had not been presented during study. These results support the view put forward by Russo, Fox, Bellinger, and Nguyen-Van-Tam (2001) that mood-congruent free recall bias in anxious individuals can be observed if the target material is encoded at a relatively shallow level. Moreover, contrary to Dowens and Calvo (2003), the current results show that the memory advantage for threat-related information in anxious individuals is not a consequence of response bias.     

Implicit Memory and Anxiety: Perceptual Identification of Emotional Stimuli

The perceptual identification paradigm was used to examine implicit memory performance in high- and low-trait anxious subjects. A series of threat-related and neutral words was presented in different colours during the encoding phase. Subjects were required to encode the stimuli by naming the colour while ignoring the semantic content of the words (Experiment 1), by simply reading the words (Experiment 2) or by naming the colour of the words and the words themselves (Experiment 3). Experiment 1 demonstrated the predicted emotional Stroop effect, with high-trait subjects taking relatively longer than low-trait subjects to name the colour of the threat-related as compared to the neutral stimuli. All three experiments revealed a significant implicit memory effect overall, with more primed than unprimed words being correctly identified during the perceptual identification task. Subjects in all experiments also identified more of the threat-related than neutral words. Although Experiment 2 found that, overall, the high-trait subjects identified relatively fewer threat-related words than neutral words in comparison to the low-trait subjects, none of the experiments offered any support for the prediction of a threat-related implicit memory bias in hightrait anxiety.     

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.     

Seeking the source of emotional Stroop interference effects in PTSD: A study of P3s to traumatic words

We investigated the source of emotional Stroop interference effects in posttraumatic stress disorder (PTSD) by measuring reaction times and P3 latencies and amplitudes to personal traumatic, personal positive, and neutral words in a modified Stroop paradigm. Individuals with PTSD were slower to indicate word color, especially for traumatic words, thereby replicating emotional Stroop interference in PTSD. Individuals with PTSD also had significantly reduced and delayed P3 components across word types. Across diagnostic groups, frontal P3 amplitudes were larger to personal positive and traumatic words compared to standard neutral words. However, the absence of Diagnosis x Word Type interactions for P3 measures suggests that individuals with PTSD do not differ from individuals without PTSD in the encoding and recognition of the color of traumatic relative to nontraumatic words, and that Stroop interference does not occur during these early stages of processing.     

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.     

Strategic regulation of cognitive control by emotional salience: A neural network model

We present a neural network model of stimulus processing, which uses a mechanism of adaptive attentional control to regulate the moment to moment deployment of attention according to both the demands of the current task, and the demands of emotionally salient information. This mechanism allows negative emotional information to reduce cognitive control to aid in the detection of threats, which produces a momentary withdrawal from the current task set to allow unbiased processing of available information. The combination of cognitive and emotional regulation of task set allows this model to address inter-trial aspects of emotional interference in colour naming. In particular, we focus on the nature of the emotional interference in colour naming (McKenna & Sharma, 2004) as well as in word reading (Algom, Chajut, & Lev, 2004) and show how this form of interference is functionally distinct from the classic Stroop effect. Our model addresses a range of findings in colour naming and word reading tasks and is informed by recent neuroimaging data concerning the interaction between the anterior cingulate and prefrontal cortices. The model is used to explore the interface between cognition and emotion with a series of predictions, including a qualitative distinction between state and trait forms of anxiety.