A longitudinal model of executive function development from birth through adolescence in children born very or extremely preterm

Executive function deficits are often reported as a specific weakness in preterm children. Yet, executive function development is still not fully understood. In a prospective longitudinal study, 115 preterm born children, ≤31 weeks of gestation, were recruited at birth and subject to neuropsychological assessments at ages 5.5 and 18 years. By applying Miyake and colleagues’ integrative framework of executive function to our data, two core components of executive function, working memory and cognitive flexibility, were identified through confirmatory factor analysis. Developmental stability was investigated in a serial multiple mediator structural equation model. Biological, medical, and social factors as well as mental development at 10 months were entered as predictors. Both components of executive function were highly stable from 5.5 to 18 years. Gestational age, intrauterine growth, lack of perinatal medical complications, and female sex were positively related to mental development at 10 months, which together with parental education influenced both core executive functions at 5.5 years. Working memory at 5.5 years mediated outcome in working memory at 18 years. In addition to the mediation of cognitive flexibility at 5.5 years, perinatal medical complications and restricted intrauterine growth had a continued direct negative impact on cognitive flexibility at 18 years. The application of a theoretical framework added to our understanding of executive function development in preterm born children. The study supports early identification of executive deficits among children born preterm, as deficits are unlikely to diminish with maturation.     

The precursors of mathematics learning: Working memory,phonological ability and numerical competence

This research aims at identifying the precursors of mathematics learning at the beginning of primary school. There are few experimental studies on this topic and existing ones use between-subjects designs and correlation analysis. This paper analyses longitudinal data to investigate whether the relationship between basic abilities and mathematics learning is causally interpretable, rather than one where cognitive abilities are correlated to early mathematics learning in a cross-section design.     

The social costs of extrinsic relative to intrinsic goal pursuits: their relation with social dominance and racial and ethnic prejudice

Self-determination theory's distinction between extrinsic and intrinsic goal pursuits offers a possible explanation for ethnic and racial prejudice. Because extrinsic relative to intrinsic goal pursuits (E/I) stimulate interpersonal competition, they were expected to predict social dominance orientation (SDO), which, in turn, would predict racial and ethnic prejudice. Results of a first cross-sectional study showed that E/I goal pursuits are positively associated with prejudice and that SDO partially mediates this association. In a second longitudinal study, we replicated these results. In addition, however, we found evidence for a reciprocal relationship between E/I goal pursuit and SDO. Moreover, both E/I goal pursuit and SDO had an independent effect on increases in prejudice. Implications of these findings are discussed.     

Emotional irritation before mental stress is associated with enhanced peripheral norepinephrine

Research suggests equivocal findings on associations of catecholamines and mood. Our study investigated the associations of emotional state, blood pressure and catecholamines in 55 healthy males undergoing mental stress. We especially checked the reported link between norepinephrine (NE) and emotional irritation. Blood pressure (SBP, DBP) and heart rate (HR) were continuously monitored. NE and epinephrine (EPI) were measured before, after, and 20 minutes after stress. Participants were divided into irritated versus non-irritated and anxious versus non-anxious subjects by median split on their baseline questionnaires. The task elicited significant cardiovascular, hormonal, and psychological stress responses. NE levels were significantly correlated with irritation before stress. Irritated subjects showed significantly higher DBP and NE than non-irritated subjects. The higher NE and DBP levels in the irritated participants suggest detrimental psycho-physiological interrelations promoting the development of stress-mediated cardiovascular diseases. Heightened emotional irritation before stress may be regarded as a psychological risk factor.     

Biassed processing of persuasive information: on the functional equivalence of cues and message arguments

Research on persuasion has shown that inferences based on heuristic or peripheral cues can bias the subsequent processing of persuasive messages. Two studies (total N = 296) examined the additional possibilities that a message argument can serve as a biassing factor and cue‐related information can serve as the target of processing bias. It was demonstrated that a message argument can bias (a) the processing of subsequent other message arguments (Study 1) and (b) the processing of subsequent cue information (Study 2). Results are discussed within dual‐process models and the recently developed unimodel of persuasion. Copyright © 2007 John Wiley & Sons, Ltd.     

Prevalence of Psychiatric Disorders Among Children of Different Ethnic Origin

The present study assesses the population prevalence of DSM-IV disorders among native and immigrant children living in low socio-economic status (SES) inner-city neighborhoods in the Netherlands. In the first phase of a two-phase epidemiological design, teachers screened an ethnically diverse sample of 2041 children aged 6–10 years using the Strengths and Difficulties Questionnaire (SDQ). In the second phase, a subsample of 253 children was psychiatrically examined, while their parents were interviewed. In addition, teachers completed a short questionnaire about 10 DSM-IV items. Prevalence was estimated using the best-estimate diagnosis based on parent, child and teacher information. Projected to the total population, 11% of the children had one or more impairing psychiatric disorders, which did not differ between native and non-native children. In the total group a clear relationship was observed between the prevalence of psychiatric disorders and gender, parental psychopathology, peer problems and school problems, but not among all ethnic groups separately. This study suggests that the prevalence of psychiatric disorders among non-treated minority and native children in low SES inner-city neighborhoods does not materially differ. However, associated mechanisms may be influenced by ethnicity.     

Cueing attention by relative motion in the periphery of the visual field

Sudden changes of visual stimulation attract attention. The observer's body motion generates retinal-flow field patterns containing information about his/her own speed and trajectory and relative motion of other objects. We investigated the effectiveness of relative motion as an attentional cue and compared it with conventional cueing by appearance of a frame in the far periphery of the visual field. In a group of ten subjects, contrast thresholds for the perception of static Gabor grating orientation [four alternative non-forced-choice (4ANFC)] task were determined at 20 degrees, 30 degrees, 40 degrees, and 60 degrees eccentricity. Subsequently, near-threshold discrimination performance of Gabor pattern orientation without versus with a ring-shaped cue was measured at the same positions. The same Gabor patterns were then presented embedded in a random-dot flow field, and uncued discrimination performance was compared with performance after presentation of a relative-motion cue (RMC), ie a small random-dot field with motion in the opposite direction of the flow field. Both the conventional ring cue and the RMC induced significantly increased discrimination performance at all test locations. With the parameters chosen for this study, the RMC was slightly less effective than the conventional cue, but its effects were somewhat more pronounced in the far periphery of the visual field. Thus, relative motion is a powerful cue to attract attention to peripheral visual objects and improves performance as effectively as a conventional ring cue. The findings have practical relevance for everyday life, in particular for tasks like driving and navigation.     

Dissociative style and individual differences in verbal working memory span

Dissociative style is mostly studied as a risk factor for dissociative pathology, but it may also reflect a fundamental characteristic of healthy information processing. Due to the close link between attention and working memory and the previous finding of enhanced attentional abilities with a high dissociative style, a positive relationship was also expected between dissociative style and verbal working memory span. In a sample of 119 psychology students, it was found that the verbal span of the high-dissociative group was about half a word larger than of the medium and low-dissociative groups. It is suggested that dissociative style may be one of only very few individual differences that is directly relevant to consciousness research.     

Loading working memory enhances affective priming

Stronger affective priming (Murphy & Zajonc, 1993) with suboptimal (i.e., reduced consciousness) than with optimal (i.e., full consciousness) prime presentation suggests that nonconscious processes form an important part of emotions. Merikle and Joordens (1997) have argued that both impoverished presentation and divided attention can produce suboptimal conditions and result in parallel effects. We manipulated attention by means of a concurrent working memory load while keeping presentation duration constant, as participants evaluated Japanese ideographs that were preceded by happy, neutral, or angry faces (affective priming) and male or female faces (nonaffective priming). In contrast to nonaffective priming, affective priming was larger with divided attention than with focused attention. It is concluded that manipulations of stimulus quality and of attention can both be used to probe the distinction between conscious and nonconscious processes and that the highest chances of obtaining the pattern of stronger priming with suboptimal presentation than with optimal presentation occur in the affective domain.     

Why aren’t all deep superior colliculus neurons multisensory? A Bayes’ ratio analysis

Multisensory neurons in the deep superior colliculus (SC) show response enhancement to cross-modal stimuli that coincide in time and space. However, multisensory SC neurons respond to unimodal input as well. It is thus legitimate to ask why not all deep SC neurons are multisensory or, at least, develop multisensory behavior during an organism's maturation. The novel answer given here derives from a signal detection theory perspective. A Bayes' ratio model of multisensory enhancement is suggested. It holds that deep SC neurons operate under the Bayes' ratio rule, which guarantees optimal performance-that is, it maximizes the probability of target detection while minimizing the false alarm rate. It is shown that optimal performance of multisensory neurons vis-à-vis cross-modal stimuli implies, at the same time, that modality-specific neurons will outperform multisensory neurons in processing unimodal targets. Thus, only the existence of both multisensory and modality-specific neurons allows optimal performance when targets of one or several modalities may occur.