The interaction between schizotypy and latent inhibition: modulation by experimental parameters

Two recent experiments (Della Casa et al., in press) yielded the typical reduced latent inhibition (LI) in high vs low schizotypy subjects after a slow, irregularly presented masking task (Stroop task), and reduced LI in low vs high schizotypy subjects after a fast, regularly presented masking task. The present experiment was aimed at testing whether speed or regularity was responsible for the different results. The present slow, regular experiment replicated the results of the former slow, irregular experiment, i.e. reduced LI in high schizotypals and significant LI in low schizotypals, indicating that speed and not regularity is the critical experimental variable. The modulation of the schizotypy—latent inhibition relationship can be attributed to differences in attentional resources or the time available to process the to-be-target stimuli during preexposure, in accordance with the hypothesis of Lubow and Gewirtz, 1995 that automatic processing of these stimuli is critical for the development of latent inhibition in adult humans. In addition, results on Stroop and negative priming effects are presented.     

Independent race of colour and word can predict the Stroop effect

Mainstream theories of the Stroop effect suggest that faster colour classification on congruent trials (say, the word RED printed in red colour) relative to incongruent trials (GREEN in red) is due to channel interaction. Namely, information from the irrelevant word channel perturbs processing of the print colour, causing in turn slower processing of incongruent displays. In this note, I advance a new model in which colour and word are processed in parallel and completely independent channels. The Stroop effect is then the outcome of signal redundancy in congruent displays, where both colour and word contribute to the same response. Numerical computations show that the model can produce the Stroop effect (along with high accuracy rates) for a subset of parameter values. Thus, it provides a proof of existence for a separate channel theory, and a challenge to many existing theories.     

An fMRI study of the social competition in healthy subjects

Social interaction requires the ability to infer another person’s mental state (Theory of Mind, ToM) and also executive functions. This fMRI study aimed to identify the cerebral correlates activated by ToM during a specific social interaction, the human-human competition. In this framework, we tested a conflict resolution task (Stroop) adapted to a virtual situation of competition. The participants were instructed to play in order to win either against a human-like competitor (human-human competition) or against a non-human competitor (human-machine competition). Only the human-human competition requires ToM as this type of competition is performed under social interaction. We identified first the classical network of executive regions activated by Stroop. Secondly, we identified the social (human-human) competition regions, represented by the bilateral superior and inferior frontal gyri, the anterior cingulate, the insula, the superior and anterior temporal, the hippocampus, the fusiform gyrus, the cuneus and the precuneus. Finally, we identified the executive regions that were modulated by the human-human competition, i.e., the executive control regions additionally activated when mentalizing in the context of social competition. They constituted a network predominant to the right and composed of the superior and middle frontal, anterior cingulate, insula and fusiform gyrus. We suggest that our experimental paradigm may be useful in exploration of the cerebral correlates of social adjustments in several situations such as psychiatric disorders presenting executive and social dysfunctions.     

情绪Stroop效应：威胁驱动还是反应偏差？

为了考查情绪Stroop效应的产生机制是威胁驱动还是反应偏差,本研究进行了两个实验.实验一用一般负性情绪词语和中性词语作为实验材料,实验二用威胁性的情绪图片和中性图片作为实验材料.每个实验均要求一组被试做按键反应,另一组被试做摇杆反应.结果发现,当实验材料为词语时,未出现情绪Stroop效应;当实验材料为威胁性图片时,无论是趋向性反应方式还是回避性反应方式,都出现了情绪Stroop效应.本研究结果支持威胁驱动机制.     

Age-related qualitative differences in post-error cognitive control adjustments

Detecting an error signals the need for increased cognitive control and behavioural adjustments. Considerable development in performance monitoring and cognitive control is evidenced by lower error rates and faster response times in multi-trial executive function tasks with age. Besides these quantitative changes, we were interested in whether qualitative changes in balancing accuracy and speed contribute to developmental progression during elementary school years. We conducted two studies investigating the temporal and developmental trajectories of post-error slowing in three prominent cognitive conflict tasks (Stroop, Simon, and flanker). We instructed children (8-, 10-, and 12-year-old) and adults to respond as fast and as accurately as possible and measured their response times on four trials after correct and incorrect responses to a cognitive conflict. Results revealed that all age groups had longer response times on post-error versus post-correct trials, reflecting post-error slowing. Critically, slowing on the first post-error trial declined with age, suggesting an age-related reduction in the orienting response towards errors. This age effect diminished on subsequent trials, suggesting more fine-tuned cognitive control adjustments with age. Overall, the consistent pattern across tasks suggests an age-related change from a relatively strong orienting response to more balanced cognitive control adaptations.     

挫折情境下自我肯定对执行功能的影响

为探讨挫折情境下自我肯定对执行功能的影响,创设挫折和非挫折情境,采用价值观自我肯定干预,通过Stroop范式和2-back范式分别测量抑制控制和工作记忆的刷新能力。结果发现,挫折情境下的Stroop任务和2-back任务反应时均高于非挫折情境;挫折情境下自我肯定组在Stroop任务和2-back任务上的反应时均显著低于非自我肯定组,而非挫折情境下两组的反应时没有显著性差异;Stroop效应量在情境与肯定条件上的交互作用不显著。结果表明挫折降低了执行功能的任务表现,自我肯定干预能够改善挫折情境下执行功能相关的任务成绩,促进了个体对工作记忆任务的刷新能力和Stroop任务的认知表现,但对抑制控制能力的改善没有明显作用。     

Anxiety and speaking in people who stutter: An investigation using the emotional Stroop task

People with anxiety disorders show an attentional bias towards threat or negative emotion words. This exploratory study examined whether people who stutter (PWS), who can be anxious when speaking, show similar bias and whether reactions to threat words also influence speech motor planning and execution. Comparisons were made between 31 PWS and 31 fluent controls in a modified emotional Stroop task where, depending on a visual cue, participants named the colour of threat and neutral words at either a normal or fast articulation rate. In a manual version of the same task participants pressed the corresponding colour button with either a long or short duration. PWS but not controls were slower to respond to threat words than neutral words, however, this emotionality effect was only evident for verbal responding. Emotionality did not interact with speech rate, but the size of the emotionality effect among PWS did correlate with frequency of stuttering. Results suggest PWS show an attentional bias to threat words similar to that found in people with anxiety disorder. In addition, this bias appears to be contingent on engaging the speech production system as a response modality. No evidence was found to indicate that emotional reactivity during the Stroop task constrains or destabilises, perhaps via arousal mechanisms, speech motor adjustment or execution for PWS.Educational objectives: The reader will be able to: (1) explain the importance of cognitive aspects of anxiety, such as attentional biases, in the possible cause and/or maintenance of anxiety in people who stutter, (2) explain how the emotional Stroop task can be used as a measure of attentional bias to threat information, and (3) evaluate the findings with respect to the relationship between attentional bias to threat information and speech production in people who stutter.     

Incidental memory for colour word associates processed in colour naming and reading aloud tasks: is a blue ocean more memorable than a yellow one?

ABSTRACT

Congruency effects for colour word associates (e.g., ocean) have been reported in Stroop colour naming tasks. However, incidental memory for such words after word reading and colour naming tasks has not been examined. In the current study, participants incidentally recalled colour word associates (e.g., ocean) and neutral words (e.g., lawyer) immediately after naming their font colour (Experiment 1a) or reading them aloud (Experiment 1b). In both tasks, recall was better for congruent colour word associates (e.g., ocean appearing in blue) than incongruent colour word associates (e.g., ocean appearing in green) or neutral items (lawyer appearing in blue).

This outcome is consistent with the idea that co-activation of a semantic colour code and a lexical representation strengthens the episodic memory representation and makes it more accessible.     

Reflection-Impulsivity in Mexican Children: Cross-Cultural Relationships

Urban Mexican children aged 5 (n = 23) and 9 (n = 87) years were given the Matching Familiar Figures Test (MFFT). The results indicate that the MFFT was a valid test of cognitive style for Mexican children. The younger children's MFFT performance was characterized as fast and inaccurate in relation to the older children's performance, which was slower and more accurate. Cross-cultural comparisons of Mexican MFFT scores with normative data from America, Japan, and Israel indicated that Mexican children were relatively impulsive in cognitive style in relation to children of other cultures. Potential factors contributing to these cross-cultural differences are discussed here.     

Changes in Skin Potentials During the Psychogalvanic Reflex

Researchers have shown that working memory is related to a variety of high-level cognitive processes. However, the results of recent research have suggested that may be because of its role in attentional control. In the present experiment, the authors investigated that hypothesis by using an attentional interference task with musical stimuli. Listeners were asked to monitor one ear for either a clarinet or violin tone and to ignore any information in the other ear. On some of the trials, they heard only one tone and on other trials, either the same instrument in both ears or different instruments. Individual differences were measured in working memory and musical experience. The results showed more attentional interference in the different-instrument condition for participants with lower working memory scores, which suggested that working memory involves the ability to control attention to inhibit irrelevant information.