Impaired inhibition of prepotent motor tendencies in Friedreich ataxia demonstrated by the Simon interference task

Friedreich ataxia (FRDA) is the most common of the genetically inherited ataxias. We recently demonstrated that people with FRDA have impairment in motor planning - most likely because of pathology affecting the cerebral cortex and/or cerebello-cortical projections. We used the Simon interference task to examine how effective 13 individuals with FRDA were at inhibiting inappropriate automatic responses associated with stimulus-response incompatibility in comparison with control participants. Participants had to respond to arrow targets according to two features which were either congruent or incongruent. We found that individuals with FRDA were differentially affected in reaction time to incongruent, compared with congruent stimuli, when compared with control participants. There was a significant negative correlation between age of onset and the incongruency effect, suggesting an impact of FRDA on the developmental unfolding of motor cognition, independent of the effect of disease duration. Future neuroimaging studies will be required to establish whether this dysfunction is due to cerebellar impairment disrupting cerebro-ponto-cerebello-thalamo-cerebral loops (and thus cortical function), direct primary cortical pathology, or a possible combination of the two.     

Individual differences of visual imagery ability in the benefit of a survival judgment task

This study investigated whether or not visual imagery ability affected the benefit of a survival judgment task. Based on the median split of their VVIQ score, 92 undergraduate students were classified as either high imagers (n = 46) or low imagers (n = 46). In the survival task, participants were requested to judge whether an item presented in the form of two Chinese characters was necessary or not in a survival situation. In the image judgment task, participants were requested to judge whether an item presented in the form of two Chinese characters arouses mental images or not. Participants were presented 18 concrete nouns at 4 s intervals in each condition. In both the survival judgment and the image judgment tasks, high imagers recalled more words than low imagers did. This result showed that imagery ability influenced the benefit of the survival judgment task. These results were discussed from the functional perspective of memory. Finally, we proposed the combination hypothesis, which combined elaboration and functional perspectives to explain the benefit of the survival judgment task.     

Brain functions associated with verbal working memory tasks among young males with alcohol use disorders

This study aimed to investigate the differences in brain functions during verbal working memory between individuals with alcohol use disorders (AUD) and normal controls. fMRI was used to scan brain activations associated with verbal working memory while participants performed 2-back and 0-back tasks. A total of 21 young male college students participated in the study. Eleven of those who clinically met the criteria for AUD were assigned to the AUD group, whereas ten demographically similar subjects who were social drinkers but not AUD were assigned to the normal control group. The AUD group showed less activation in bilateral frontal and precentral, left superior temporal, left superior parietal, and left cerebellar cortex during the 2-back task relative to 0-back task compared to the normal control group. In contrast, the control group showed less activation only in the right uncus than the AUD group. These results suggest that subjects with AUD present abnormality in brain functioning during verbal working memory.     

Adaptive criterion setting in perceptual decision making

Pigeons responded in a perceptual categorization task with six different stimuli (shades of gray), three of which were to be classified as "light" or "dark", respectively. Reinforcement probability for correct responses was varied from 0.2 to 0.6 across blocks of sessions and was unequal for correct light and dark responses. Introduction of a new reinforcement contingency resulted in a biphasic process of adjustment: First, choices were strongly biased towards the favored alternative, which was followed by a shift of preference back towards unbiased choice allocation. The data are well described by a signal detection model in which adjustment to a change in reinforcement contingency is modeled as the change of a criterion along a decision axis with fixed stimulus distributions. Moreover, the model shows that pigeons, after an initial overadjustment, distribute their responses almost optimally, although the overall benefit from doing so is extremely small. The strong and swift effect of minute changes in overall reinforcement probability precludes a choice strategy directly maximizing expected value, contrary to the assumption of signal detection theory. Instead, the rapid adjustments observed can be explained by a model in which reinforcement probabilities for each action, contingent on perceived stimulus intensity, determine choice allocation.     

数学学习困难初中生的N-back任务表现特征

目的：分析数学学习困难初中生与学习优秀初中生的核心认知过程机制差异。方法：采用N-back任务作为测查工作记忆能力的指标,分析初中42名数困生和53名数优生的表现差异。结果：两组学生在0-back任务中无显著差异,在1-back和2-back任务中的差异逐渐增大。回归分析表明2-back和1-back任务对数学成绩有显著影响。结论：1）随着认知负荷增高,数困生和数优生的表现差距增大。数学学习困难的核心认知缺损是工作记忆能力而非简单认知加工过程。2）N-back任务能有效预测数学学习成绩。     

Lack of correlation between hypnotic susceptibility and various components of attention

The purpose of our study was to measure the relationship between performance on various attentional tasks and hypnotic susceptibility. Healthy volunteers (N = 116) participated in a study, where they had to perform several tasks measuring various attention components in a waking state: sustained attention, selective or focused attention, divided attention and executive attention in task switching. Hypnotic susceptibility was measured in a separate setting by the Waterloo-Stanford Groups Scale of Hypnotic Susceptibility, Form C (WSGC).We found no significant correlation between any of the attentional measures and hypnotic susceptibility. Highly hypnotizables did not prove to be superior to or worse than the other individuals in any of the tests.These results do not support the neuropsychophysiological model of hypnosis, as they show no consistent relationship between hypnotic susceptibility and waking attentional performance.     

Role of face‐to‐face and computer‐mediated communication time in the cohesion and performance of mixed‐mode groups

Although the rapid development of information technology has led to the increasing use of computer‐mediated communication (CMC), few studies have examined the relational aspect of mixed‐mode groups that use both face‐to‐face (FTF) communication and CMC. A field study comprising 42 student groups was conducted to assess the relationships among communication time, cohesion, and performance in mixed‐mode groups. The findings suggest that time spent in FTF communication significantly predicted group social cohesion, but time spent in CMC did not. In contrast, group task cohesion was predicted by time spent in CMC but not by time spent in FTF communication. Time spent in CMC was also a strong predictor of group task performance. These results suggest that FTF communication contributes to the social aspect of mixed‐mode groups and that CMC is beneficial to their task‐related aspect. The findings of mediation analyses showed a significant indirect effect among time spent in FTF communication, group social cohesion, and group contextual performance. In other words, time spent in FTF communication had a positive effect on group social cohesion, which in turn positively affected group contextual performance. However, no mediating effect was found among time spent in CMC, group task cohesion, and group task performance. Theoretical and practical implications of these findings are discussed.     

Metaphilosophical Criteria for Worldview Comparison

Philosophy lacks criteria to evaluate its philosophical theories. To fill this gap, this essay introduces nine criteria to compare worldviews, classified in three broad categories: objective criteria (objective consistency, scientificity, scope), subjective criteria (subjective consistency, personal utility, emotionality), and intersubjective criteria (intersubjective consistency, collective utility, narrativity). The essay first defines what a worldview is and exposes the heuristic used in the quest for criteria. After describing each criterion individually, it shows what happens when each of them is violated. From the criteria, it derives assessment tests to compare and improve different worldviews. These include the is‐ought, ought‐act, and is‐act first‐order tests; the critical and dialectical second‐order tests; the mixed‐questions and first‐second‐order third‐order tests; and the we‐I, we‐it, and it‐I tests. The essay then applies these criteria and tests to a concrete example, comparing the Flying Spaghetti Monster deity with Intelligent Design. For another application, it draws more general fruitful suggestions for the dialogue between science and religion.     

Trait aggression is related to anger-modulated deficits in response inhibition

The goal of the present study was to investigate the role of emotion-modulated response inhibition in individual difference in the disposition towards aggressive behavior (i.e. trait aggression). One hundred and twelve undergraduate participants completed a behavioral measure of emotion modulated response inhibition (an emotional go/no-go task), self-report measures previously shown to predict aggression (Big-5 traits, impulsivity), and the Aggression Questionnaire (AQ) as a measure of trait aggression. Results show that deficient inhibition to angry, but not happy, faces were related to trait aggression but not to other traits. These findings provide support for the role of specific top down executive control mechanisms in the regulation of aggressive tendencies and highlight the importance of examining these mechanisms in an emotional context.     

A Pilot Study of Electrocortical Activity in Dysfunctional Anger: Decreased Frontocortical Activation,Impaired Attention Control,and Diminished Behavioral Inhibition

Dysfunctional anger, though not a primary clinical diagnosis per se, does present clinically as a pathological mood for which treatment is sought. Few studies have probed the neurocortical correlates of dysfunctional anger or assessed if cognitive processes, such as attention, are altered in dysfunctional anger. Though dysfunctional and high trait anger appears to be associated with biased processing of anger‐eliciting information, few studies have examined if dysfunctional anger modulates attention more generally. This is a notable gap as volitional attention control is associated with effective emotive regulation, which is impaired in dysfunctional anger and in associated acts of aggression. In this pilot study, we examined performance and electroencephalographic (EEG) profiles during a 12‐min continuous performance task (CPT) of sustained attention in 15 adults with dysfunctional anger (Anger group) and 14 controls (control group). The Anger group had fewer hits at the end of the CPT, which correlated with decreased frontocortical activation, suggesting decreased engagement of frontal circuits when attention is taxed. The Anger group had more false alarms overall indicating impaired response inhibition. Increased right cortical activation during the initial portion of CPT existed in the Anger group, perhaps reflecting greater engagement of frontal circuits (i.e. effort) during initial stages of the task compared to controls. Finally, increased overall beta₁ power, suggesting increased cortical activation, was noted in the Anger group. These EEG patterns suggest a hypervigilant state in dysfunctional anger, which may interfere with effective attention control and decrease inhibition. Such impairments likely extend beyond the laboratory setting, and may associate with aggressive acts in real life. Aggr. Behav. 38:469‐480, 2012. © 2012 Wiley Periodicals, Inc.