Esther H. H. Keulers

Subtypes of learning disabilities: neuropsychological and behavioural functioning of 495 children referred for multidisciplinary assessment

Aim of the present study was two fold: (1) to evaluate the course of referring and diagnosing Learning Disabilities (LD) and the contribution of multidisciplinary assessment and (2) to describe characteristics of three LD subtypes: Attention with or without Motor function Disabilities (AMD), Verbal Learning Disabilities (VLD) and Non-Verbal Learning Disabilities (NVLD). Diagnostics, behavioural and neuropsychological data from 495 children aged 6–17 years were described. First, AMD and VLD was the most frequent LD. Multidisciplinary assessment could contribute to the diagnostic process of LD, especially in diagnosing uncommon LD and comorbidities. Secondly, behavioural ratings, information processing, attention regularity and visual-motor integration proved to be most sensitive in discriminating between the three LD subtypes. However, diagnosing NVLD requires additional developmental information. Multiple discriminant function analysis correctly classified 61.7% of a selection of the present sample into LD subtypes as diagnosed by the multidisciplinary team. It is believed that the three subtypes are clinically relevant and suggestions are made to test the present classification functions in an independent sample, preferably diagnosed using a structured diagnostic interview.

Age, Sex, and Pubertal Phase Influence Mentalizing About Emotions and Actions in Adolescents

This study examined (1) emotional versus cognitive developmental trajectories and (2) the influence of age-extrinsic factors (i.e., sex and puberty). Using a cross-sectional design, adolescents (N = 252) divided into four age-groups (ages 13, 15, 17, 19) performed two versions of a mentalizing task, about emotions and actions, as well as the Tower task. First, performance on all tasks improved linearly into late adolescence (age 19). Thus no differential trajectories were found for emotional versus cognitive development. Second, girls outperformed boys in mentalizing speed regarding both emotions and actions. In boys, a later pubertal phase was associated with increased mentalizing speed after controlling for age-group.

Development of Inattention, Impulsivity, and Processing Speed as Measured by the d2 Test: Results of a Large Cross-sectional Study in Children Aged 7–13

The development of three aspects of selective attention was studied in 451 Dutch schoolchildren attending second to sixth grade. Selective attention was measured with the d2 Test of attention. The largest age differences were found for processing speed that continued to improve until the sixth grade. Impulsivity, as measured by the percentage of errors of commission, decreased until the fourth grade. Inattention, measured by the percentage of errors of omission, was stable in all grades. Processing speed and impulsivity were correlated with the score on the Attention Problems subscale of the Child Behavior Checklist. These results imply that selective attention continues to develop, at least, until the end of elementary school. The findings are support for a step-wise model of cognitive development (P. Anderson, 2002).

Developmental changes between ages 13 and 21 years in the extent and magnitude of the BOLD response during decision making

Developmental neuroimaging results have suggested a progression in focalization in functional activations from childhood to adulthood. The mechanisms underlying this process are thought to be an age-related decrease in activation extent as well as an increased magnitude in task-related areas. The present study aimed to evaluate these notions while controlling for confounders that may bias towards focalization. We used adolescent subjects in small age ranges. In addition, head motion corrections were incorporated in statistical analyses and regions of interest were identified for each participant separately to overcome inter-individual variability in anatomy and functional organization. Activation patterns of 13-, 17- and 21-year-old males were compared during the decision phase of a challenging and complex gambling paradigm. The BOLD amplitude enhanced with increasing age, modulated by task conditions. First, response amplitude during difficult, endogenous relative to exogenous decisions increased with age. This decision difficulty effect was most pronounced in 21-year-olds, both in areas associated with task execution and default mode areas. Second, deciding to pass as opposed to gamble exerted more effort in inferior frontal and parietal areas only by 13- and 17-year-olds. There was neither an age-related decrease in activation extent, nor any qualitative shifts in activated areas as suggested by the focalization hypothesis. These results suggest that although different age groups throughout adolescence engage similar brain areas during decision making, the response magnitude in these areas increases with age particularly during difficult task conditions, providing that confounding factors are controlled.

Maturation of task-induced brain activation and long range functional connectivity in adolescence revealed by multivariate pattern classification

The present study uses multivariate pattern classification analysis to examine maturation in task-induced brain activation and in functional connectivity during adolescence. The multivariate approach allowed accurate discrimination of adolescent boys of respectively 13, 17 and 21years old based on brain activation during a gonogo task, whereas the univariate statistical analyses showed no or only very few, small age-related clusters. Developmental differences in task activation were spatially distributed throughout the brain, indicating differences in the responsiveness of a wide range of task-related and default mode regions. Moreover, these distributed age-distinctive patterns generalized from a simple gonogo task to a cognitively and motivationally very different gambling task, and vice versa. This suggests that functional brain maturation in adolescence is driven by common processes across cognitive tasks as opposed to task-specific processes. Although we confirmed previous reports of age-related differences in functional connectivity, particularly for long range connections (>60mm), these differences were not specific to brain regions that showed maturation of task-induced responsiveness. Together with the task-independency of brain activation maturation, this result suggests that brain connectivity changes in the course of adolescence affect brain functionality at a basic level. This basic change is manifest in a range of tasks, from the simplest gonogo task to a complex gambling task.

The effect of perspective and content on brain activation during mentalizing in young females

In the present functional magnetic resonance imaging (fMRI) study, we investigated the role of different brain regions in separate aspects of mentalizing. Young females aged 18–19 years were asked to imagine a social situation and answer a question. Perspective, self and other, as well as content, emotion, and behavior, were varied. Activation was observed in the left precuneus, left temporoparietal junction, left medial prefrontal cortex and left middle temporal gyrus. Left precuneus and left temporoparietal junction were recruited more when taking the perspective of other than when taking the perspective of self. Medial prefrontal areas might be more involved during mentalizing about emotion versus baseline than about behavior versus baseline.

The association between cortisol and the BOLD response in male adolescents undergoing fMRI

MRI participation has been shown to induce subjective and neuroendocrine stress reactions. A recent aging study showed that cortisol levels during fMRI have an age-dependent effect on cognitive performance and brain functioning. The present study examined whether this age-specific influence of cortisol on behavioral and brain activation levels also applies to adolescence. Salivary cortisol as well as subjective experienced anxiety were assessed during the practice session, at home, and before, during and after the fMRI session in young versus old male adolescents. Cortisol levels were enhanced pre-imaging relative to during and post-imaging in both age groups, suggesting anticipatory stress and anxiety. Overall, a negative correlation was found between cortisol output during the fMRI experiment and brain activation magnitude during performance of a gambling task. In young but not in old adolescents, higher cortisol output was related to stronger deactivation of clusters in the anterior and posterior cingulate cortex. In old but not in young adolescents, a negative correlation was found between cortisol and activation in the inferior parietal and in the superior frontal cortex. In sum, cortisol increased the deactivation of several brain areas, although the location of the affected areas in the brain was age-dependent. The present findings suggest that cortisol output during fMRI should be considered as confounder and integrated in analyzing developmental changes in brain activation during adolescence.

Does strategy instruction on the Rey-Osterrieth Complex Figure task lead to transferred performance improvement on the Modified Taylor Complex Figure task? A randomized controlled trial in school-aged children

Abstract Objective: Providing children with organizational strategy instruction on the Rey Osterrieth Complex Figure (ROCF) has previously been found to improve organizational and accuracy performance on this task. It is unknown whether strategy instruction on the ROCF would also transfer to performance improvement on copying and the recall of another complex figure. Methods: Participants were 98 typically developing children (aged 9.5–12.6 years, M = 10.6). Children completed the ROCF (copy and recall) as a pretest. Approximately a month later, they were randomized to complete the ROCF with strategy instruction in the form of a stepwise administration of the ROCF or again in the standard format. All children then copied and recalled the Modified Taylor Complex Figure (MTCF). All productions were assessed in terms of organization, accuracy and completion time. Results: Organization scores for the MTCF did not differ for the two groups for the copy production, but did differ for the recall production, indicating transfer. Accuracy and completion times did not differ between groups. Performance on all measures, except copy accuracy, improved between pretest ROCF and posttest MTCF production for both groups, suggesting practice effects. Conclusion: Findings indicate that transfer of strategy instruction from one complex figure to another is only present for organization of recalled information. The increase in RCF-OSS scores did not lead to a higher accuracy or a faster copy or recall.