Prevalence, symptoms and distribution of oppositional defiant disorder

The purpose of this work was to determine the epidemiological evolution of the Oppositional Defiant Disorder (ODD) in adolescents, using a sample of Secondary School students of the region of Campo de Gibraltar (Cadiz). The students' age ranged from 12 to 16 years old. Two evaluations were completed, the first one during the school year 2001-2002 and the second one in the school year 2006-2007. The sample comprised 2310 students in the first study and 2351 students in the second one. We used a comparative-selective approach. The results of the comparison revealed a prevalence ranging from 3.77% to 3.83% of students with this disorder, maintaining the main symptoms and with some changes in its distribution as a function of the school grade. Indeed, the data showed more cases in the final courses (1st study) in contrast with a higher concentration of cases in the initial courses (2nd study). With regard to the frequency of ODD by sex, we found that whereas in the earlier study (2001-2002), the relationship between boys and girls was 3.5:1, in the school year 2006/2007, the number of boys with ODD quadrupled the number of girls.     

Associations between parental educational/occupational levels and cognitive performance in Spanish adolescents: the AVENA study

We examined the associations between parental educational/occupational levels and cognitive performance in Spanish adolescents. Cognitive performance was measured by a validated Scholar Aptitudes test in 2,162 participants. Parental educational and occupational levels were positively associated with all specific cognitive abilities and the overall score (p<001 to .04). The odds ratios of having a high cognitive performance (top quartile) in adolescents with high parental educational level were 1.6 to 1.7 times higher than for those with a low parental educational level. Similarly, the odds ratios were 1.9 to 2.4 times higher for adolescents with high parental occupational level. These findings suggest an association between parental educational/occupational levels and cognitive performance in Spanish adolescents and support the parents' role in the creation of a stimulating intellectual environment.     

Impaired finger dexterity in Parkinson's disease is associated with praxis function

A controversial concept suggests that impaired finger dexterity in Parkinson’s disease may be related to limb kinetic apraxia that is not explained by elemental motor deficits such as bradykinesia. To explore the nature of dexterous difficulties, the aim of the present study was to assess the relationship of finger dexterity with ideomotor praxis function and parkinsonian symptoms. Twenty-five patients with Parkinson’s disease participated in the study. Their left and right arms were tested independently. Testing was done in an OFF and ON state as defined by a modified version of the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS). Finger dexterity was assessed by a coin rotation (CR) task and ideomotor praxis using a novel test of upper limb apraxia (TULIA), in which the patients were requested to imitate and pantomime 48 meaningless, as well as communicative and tool-related gestures. Coin rotation significantly correlated with TULIA irrespective of the motor state and arm involved, but not with the MDS-UPDRS. This association was significantly influenced by Hoehn and Yahr stage.The strong association of finger dexterity with praxis function but not the parkinsonian symptoms indicates that impaired finger dexterity in Parkinson’s disease may be indeed apraxic in nature, yet, predominantly in advanced stages of the disease when cortical pathology is expected to develop. The findings are discussed within a cognitive-motor model of praxis function.     

Distributed attentional deficits in chronic methamphetamine abusers: evidence from the Attentional Network Task (ANT)

Objective

The goal of the present study was to examine distributed attentional functions in long-term but currently abstinent methamphetamine (MA) abusers using a task that measures attentional alertness, orienting, and conflict resolution.

Methods

Thirty currently abstinent MA abusers (1 month-5 years) and 22 healthy non-substance using adults were administered a multimodal version of the Attentional Network Task (ANT-I). In this task subjects identified the direction of a centrally presented arrow using a key press. Analyses examined the interaction between alerting tones, location cueing and congruency between the target arrows and flanking distractor stimuli.

Results

All participants were faster when an auditory tone preceded the trial onset (p < 0.001), on trials in which a valid cue preceded the location of the target arrow (p < 0.001), and on congruent trials (i.e., when all display arrows faced in the same direction) (p < 0.001). Of primary interest was the finding that MA abusers were more influenced by the conflict between the peripheral arrows and the central target arrow (p = 0.009). There were also correlations between length of drug sobriety and executive function as well as between drug-induced psychiatric symptoms and alertness.

Conclusions

These results suggest that chronic MA abusers display cognitive deficits that may reflect a specific vulnerability to distraction on a task of executive function. These findings are consistent with other studies that have reported deficits in anterior attentional systems and top-down cognitive control.     

Exposure to severe urban air pollution influences cognitive outcomes, brain volume and systemic inflammation in clinically healthy children

Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH⁺, and 10 without, WMH⁻) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH⁺ and WMH⁻ - in right parietal and bilateral temporal areas. Both WMH⁻ and WMH⁺ MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH⁺ is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood.     

Motor execution affects action prediction

Previous studies provided evidence of the claim that the prediction of occluded action involves real-time simulation. We report two experiments that aimed to study how real-time simulation is affected by simultaneous action execution under conditions of full, partial or no overlap between observed and executed actions. This overlap was analysed by comparing the body sides and the movement kinematics involved in the observed and the executed action. While performing actions, participants observed point-light (PL) actions that were interrupted by an occluder, followed by a test pose. The task was to judge whether the test pose depicted a continuation of the occluded action in the same depth angle. Using a paradigm proposed by Graf et al., we independently manipulated the duration of the occluder and the temporal advance of the test pose relative to occlusion onset (occluder time and pose time, respectively). This paradigm allows the assessment of real-time simulation, based on prediction performance across different occluder time/pose time combinations (i.e., improved task performance with decreasing time distance between occluder time and pose time is taken to reflect real-time simulation). The PL actor could be perceived as from the front or back, as indicated by task instructions. In Experiment 1 (front view instructions), evidence of action simulation was obtained for partial overlap (i.e., observed and performed action corresponded either in body side or movement kinematics), but not for full or no overlap conditions. The same pattern was obtained in Experiment 2 (back view instructions), ruling out a spatial compatibility explanation for the real-time pattern observed. Our results suggest that motor processes affect action prediction and real-time simulation. The strength of their impact varies as a function of the overlap between observed and executed actions.     

统计学习与双语认知的关系

统计学习是提取环境输入潜在规则的一种认知机制,其与语言的关联已得到证实。双语认知是学界关注的热点之一。统计学习与双语认知的关系如何?文章先介绍统计学习认知机制及其与语言的关系,然后从“统计学习能力可否预测二语学习表现”、“统计学习训练能否促进二语学习”和“双语经验能否提高统计学习能力”三个维度述评相关文献,并指出未来可从输入特征、个体差异和神经科学角度进一步探讨统计学习与双语认知的关系。     

摩尔与国王——维特根斯坦论“世界图像”的无理据性

在《论确定性》第92码段中的一场思想实验中,维特根斯坦虚构了一个国王,国王除了被告知其出生的时候即为世界开端以外从未被告知任何事情,国王因而会相信在我们看来显然是荒谬的事情。但我们能否阐明我们与国王不同的信念间谁的是正确的或是荒谬的吗?维特根斯坦在此处探讨了某人是否可能有充足的理由相信与多数人的基础信念截然相反的东西。不可能阐明某人的世界图像之基础信念是正确的吗?绝不可能证明某人的基础信念在事实面前具有正确性、真理性和恰当性吗?尝试回答上述问题后,本文将给出一种遭到有些学者明确反对的"文化相对论"的解释,并将以阐述"文化的"或"世界图像相对论"的问题作结。