Task-load manipulation in the Symbol Digit Modalities Test: An alternative measure of information processing speed

ObjectiveTo evaluate the utility of an oral fMRI-adapted version of the Symbol Digit Modalities Test (SDMT) to assess information processing speed (IPS) using three different interstimulus intervals (ISI).MethodsNineteen right-handed healthy controls performed the adapted version of the SDMT, consisting of a block design that had a total of 6 control/activation block pairs with 3 different ISIs (1.5, 2 and 2.5 s) presented in two different runs: in ascending and descending orders. The brain activation patterns during different ISIs were assessed by effective functional connectivity analysis based on independent component analysis.ResultsAs expected, all conditions yielded activations in the fronto-parietal networks (FPNs) related to attention processes. Shorter ISIs (1.5 and 2 s) not only yielded greater patterns of connectivity within fronto-parietal and occipital regions such as the FPN and fronto-occipital network (FON), but also recruited more functional networks overall. Task performance at the shortest ISI was negatively correlated with connectivity at the FPN and activity of the pre-supplementary motor area extending to the cingulate gyrus.ConclusionIncreasing IPS demands due to shorter ISIs resulted in an increased level and number of functional networks required, increased connectivity within the FPN and FON, and enhancement of the prefrontal cortex. IPS does not arise from activity of a single b area but from affective information transfer among distant cortical regions of the frontal and parietal cortices. This adapted version of the SDMT may be useful for studying alterations of IPS in clinical and nonclinical populations.     

Deeper attentional masking by lateral objects in children with autism

Autism spectrum disorder (ASD) is often associated with a detail-oriented perception and overselective attention in visual tasks, such as visual search and crowding. These results were obtained manipulating exclusively the spatial properties of the stimuli: few is known about the spatio-temporal dynamics of visual processing in ASD. In this study we employed an attentional masking (AM) paradigm comparing children with ASD and IQ-matched typically developing (TD) controls. The AM effect refers to an impaired identification of a target followed by a competitive masking object at different proximities in space and time. We found that ASD and TD groups did not differ in the AM effect provoked by the competitive object displayed in the same position of the target. In contrast, children with ASD showed a deeper and prolonged interference than the TD group when the masking object was displayed in the lateral position. These psychophysical results suggest that the inefficient attentional selection in ASD depends on the spatio-temporal interaction between competitive visual objects. These evidence are discussed in the light of the ASD altered neural connectivity hypothesis and the reentrant theory of perception.     

The Mechanisms of Space‐Time Association: Comparing Motor and Perceptual Contributions in Time Reproduction

The spatial‐temporal association indicates that time is represented spatially along a left‐to‐right line. It is unclear whether the spatial‐temporal association is mainly related to a perceptual or a motor component. In addition, the spatial‐temporal association is not consistently found using a time reproduction task. Our rationale for this finding is that, classically, a non‐lateralized button for performing the task has been used. Using two lateralized response buttons, the aim of the study was to find a spatial‐temporal association in a time reproduction task. To account for the perceptual component, reference and target stimuli were presented in different spaces through four experiments. In all experiments, a Spatial‐Temporal Association of Response Codes (STEARC) effect was found and this effect was not modulated by the spatial position of both reference and target stimuli. The results suggested that the spatial‐temporal association was mainly derived from the spatial information provided by response buttons, reflecting a motor but not visuospatial influence.     

Reading and Spelling Disabilities in Children with and Without a History of Early Language Delay: A Neuropsychological and Linguistic Study

Language delay is a frequent antecedent of literacy problems, and both may be linked to phonological impairment. Studies on developmental dyslexia have led to contradictory results due to the heterogeneity of the pathological samples. The present study investigated whether Italian children with dyslexia showed selective phonological processing deficits or more widespread linguistic impairment and whether these deficits were associated with previous language delay. We chose 46 children with specific reading deficits and divided them into two groups based on whether they had language delay (LD) or not (NoLD). LD and NoLD children showed similar, severe deficits in reading and spelling decoding, but only LD children showed a moderate impairment in reading comprehension. LD children were more impaired in phonological working memory and phonological fluency, as well as in semantic fluency, grammatical comprehension, and verbal IQ. These findings indicate the presence of a moderate but widespread linguistic deficit (not limited to phonological processing) in a subset of dyslexic children with previous language delay that does not generalize to all children with reading difficulties.     

Attention,Response Inhibition,and Face-Information Processing in Children: The Role of Task Characteristics,Age, and Gender

The aim of the study was to assess: (a) developmental changes in attention, response inhibition, and face-information processing using the new Balloons task and (b) to evaluate the association between measures derived from the task with reported behavior problems. One hundred and thirty-four typically developing children (53 boys and 81 girls) were tested with the Balloons. Their parents and teachers completed the Child Behavior Checklist. Our results validate the Balloons as a reliable task with significant effects of manipulations in difficulty level (speed, processing load, and processing type). The results suggest that face-information processing undergoes significant changes during the age period between 7 and 13 years with significant gender differences. Modest but significant correlations were found between the Balloons' measures and behavior problems.     

Mental Imagery and Post-Event Processing in Anticipation of a Speech Performance Among Socially Anxious Individuals

The present study investigated whether post-event processing (PEP) involving mental imagery about a past speech is particularly detrimental for socially anxious individuals who are currently anticipating giving a speech. One hundred fourteen high and low socially anxious participants were told they would give a 5 min impromptu speech at the end of the experimental session. They were randomly assigned to one of three manipulation conditions: post-event processing about a past speech incorporating imagery (PEP-Imagery), semantic post-event processing about a past speech (PEP-Semantic), or a control condition, (n = 19 per experimental group, per condition [high vs low socially anxious]). After the condition inductions, individuals’ anxiety, their predictions of performance in the anticipated speech, and their interpretations of other ambiguous social events were measured. Consistent with predictions, high socially anxious individuals in the PEP-Imagery condition displayed greater anxiety than individuals in the other conditions immediately following the induction and before the anticipated speech task. They also interpreted ambiguous social scenarios in a more socially anxious manner than socially anxious individuals in the control condition. High socially anxious individuals made more negative predictions about their upcoming speech performance than low anxious participants in all conditions. The impact of imagery during post-event processing in social anxiety and its implications are discussed.     

Unconscious Responses to Threatening Pictures: Interactive Effect of Trait Anxiety and Social Desirability on Skin Conductance Responses

The purpose of the present study was to examine the role of trait anxiety and social desirability on skin conductance responses (SCRs) following exposure to masked and unmasked pictures in a non‐clinical sample. The most prominent results were found with regard to masked pictures (i.e. subliminal). Higher levels of social desirability were associated with a decrease in SCRs to masked threat pictures (relative to neutral), whereas elevated levels of trait anxiety were associated with an increase in SCRs. This latter effect, however, was mainly seen among participants who simultaneously scored low on social desirability. These results were discussed in terms of trait anxiety (combined with lower social desirability scores) being associated with (i) enhanced autonomic responses to threatening information most evident at a pre‐attentive level, that (ii) may potentially be a vulnerability marker for anxiety disturbances.     

视觉词汇加工的动态神经网络及其形成

揭示大脑加工的神经网络机制成为认知神经科学研究的最新取向.本研究以视觉词汇加工脑区(VWFA)的神经功能作为切入点,探讨视觉词汇加工神经网络的动态机制及其形成.研究一考察VWFA在刺激驱动和任务调节下的动态激活,及其与语音、语义脑区所组成神经网络的动态机制.研究二通过跨文化对比以及儿童阅读发展研究,阐明语言经验对视觉词汇加工网络的塑造作用.研究三对比功能网络、静息网络以及白质纤维束联结,探讨视觉词汇加工网络的动态联结及其形成.研究结果有助于建构视觉词汇加工的神经生理模型,为基于脑科学的阅读教学和阅读障碍矫治奠定理论基础,为认知神经科学研究提供了新的思路.     

杏仁核对感觉刺激的情绪性加工:自动化过程和注意调控过程的整合

利用有限的认知资源应对多变的环境刺激,选择性注意和情绪加工一个重要的共同机制是优先化关键信息的加工。尽管情绪性刺激(特别是威胁刺激)能够影响注意资源的分配,但一些关键脑区(如杏仁核)的对情绪性刺激的加工是自动化过程还是受到注意调节一直是个有争议的问题。最新的结合高时间分辨率和高空间分辨率的神经生理记录研究表明,情绪加工的重要核团,杏仁核,对情绪性刺激的加工包含早期快速的不依赖于注意资源和认知加工负荷的自动化加工成分和晚期受到额-顶叶皮层自上而下的注意调控成分,这种功能整合证实杏仁核情绪性加工存在并行的皮层下和皮层通路。     

Self‐regulatory strength amplification through selective information processing

We propose and demonstrate that although depletion of self-regulatory strength is common, it is not inevitable. Four experiments show that under certain conditions, consumers can amplify their self-regulatory strength and, as a result, increase their ability to control their behavior. Experiments 1–3 examine the depleting effects of information processing by exposing dieters and nondieters to either cost or pleasure information about chocolate. The results of experiments 1–3 show that when dieters have the ability to monitor the costs of consumption, they are motivated to mobilize additional strength and increase their ability to self-regulate. In experiment 4 we show the practical implications of our work and show that dieters are better able to control their eating because they choose to focus more on the cost (versus pleasure) of consumption.