Regula Everts

Strengthening of Laterality of Verbal and Visuospatial Functions During Childhood and Adolescence

Cognitive functions in the childs brain develop in the context of complex adaptive processes, determined by genetic and environmental factors. Little is known about the cerebral representation of cognitive functions during development. In particular, knowledge about the development of right hemispheric (RH) functions is scarce. Considering the dynamics of brain development, localization and lateralization of cognitive functions must be expected to change with age. Twenty healthy subjects (8.6–20.5 years) were examined with fMRI and neuropsychological tests. All participants completed two fMRI tasks known to activate left hemispheric (LH) regions (language tasks) and two tasks known to involve predominantly RH areas (visual search tasks). A laterality index (LI) was computed to determine the asymmetry of activation. Group analysis revealed unilateral activation of the LH language circuitry during language tasks while visual search tasks induced a more widespread RH activation pattern in frontal, superior temporal, and occipital areas. Laterality of language increased between the ages of 8–20 in frontal (r = 0.392, P = 0.049) and temporal (r = 0.387, P = 0.051) areas. The asymmetry of visual search functions increased in frontal (r = −0.525, P = 0.009) and parietal (r = −0.439, P = 0.027) regions. A positive correlation was found between Verbal‐IQ and the LI during a language task (r = 0.585, P = 0.028), while visuospatial skills correlated with LIs of visual search (r = −0.621, P = 0.018). To summarize, cognitive development is accompanied by changes in the functional representation of neuronal circuitries, with a strengthening of lateralization not only for LH but also for RH functions. Our data show that age and performance, independently, account for the increases of laterality with age. Hum Brain Mapp, 2009.

Homeopathic treatment of children with attention deficit hyperactivity disorder: a randomised, double blind, placebo controlled crossover trial

An increasing number of parents turn to homeopathy for treatment of their hyperactive child. Two publications, a randomised, partially blinded trial and a clinical observation study, conclude that homeopathy has positive effects in patients with attention deficit hyperactivity disorder (ADHD). The aim of this study was to obtain scientific evidence of the effectiveness of homeopathy in ADHD. A total of 83 children aged 6–16 years, with ADHD diagnosed using the Diagnostic and Statistical Manual of Mental Disorders-IV criteria, were recruited. Prior to the randomised, double blind, placebo controlled crossover study, they were treated with individually prescribed homeopathic medications. 62 patients, who achieved an improvement of 50% in the Conners’ Global Index (CGI), participated in the trial. Thirteen patients did not fulfill this eligibility criterion (CGI). The responders were split into two groups and received either verum for 6 weeks followed by placebo for 6 weeks (arm A), or vice-versa (arm B). At the beginning of the trial and after each crossover period, parents reported the CGI and patients underwent neuropsychological testing. The CGI rating was evaluated again at the end of each crossover period and twice in long-term follow-up. At entry to the crossover trial, cognitive performance such as visual global perception , impulsivity and divided attention, had improved significantly under open label treatment ( P<0.0001). During the crossover trial, CGI parent–ratings were significantly lower under verum (average 1.67 points) than under placebo ( P =0.0479). Long-term CGI improvement reached 12 points (63%, P <0.0001). Conclusion:The trial suggests scientific evidence of the effectiveness of homeopathy in the treatment of attention deficit hyperactivity disorder, particularly in the areas of behavioural and cognitive functions.

Assessment of quality of life in patients with uncontrolled vs. controlled acromegaly using the Acromegaly Quality of Life Questionnaire (AcroQoL)

Objective Acromegaly is a chronic disease with an important impact on quality of life. An acromegaly disease‐generated quality of life questionnaire (AcroQoL) has recently been developed. We aimed to confirm reliability, construct validity and disease‐specificity of the AcroQoL questionnaire. Second, we investigated the effect of remission status on health‐related quality of life (HRQoL) in patients with acromegaly.

Visuospatial working memory in very preterm and term born children—Impact of age and performance

Highlights • 41 preterms performed equally to 36 controls on a visuospatial working memory task.• Preterms showed different involvement of frontal areas compared to controls.• Young and low-performing preterms recruited an atypical working memory network.• Older and high-performing preterms recruited a typical network similar to controls.• Findings point toward the use of compensational mechanisms in preterms.

Cognitive and behavioral aspects of executive functions in children born very preterm

This study investigated whether children aged between 8 and 12 years born very preterm (VPT) and/or at very low birth weight (VLBW) performed lower than same-aged term-born controls in cognitive and behavioral aspects of three executive functions: inhibition, working memory, and shifting. Special attention was given to sex differences. Fifty-two VPT/VLBW children (26 girls, 50%) born in the cohort of 1998–2003 and 36 same-aged term-born children (18 girls, 50%) were recruited. As cognitive measures, children completed tasks of inhibition (Color-Word Interference Test, D-KEFS; Delis, Kaplan, & Kramer, 2001), working memory (digit span backwards, HAWIK-IV; Petermann & Petermann, 2008), and shifting (Trail Making Test, number-letter-switching, D-KEFS; Delis et al., 2001). As behavioral measures, mothers completed the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000). Scales of interest were inhibit, working memory, and shift. Analyses of the cognitive aspects of executive functions revealed that VPT/VLBW children performed significantly lower than controls in the shifting task but not in the working memory and inhibition tasks. Analyses of behavioral aspects of executive functions revealed that VPT/VLBW children displayed more problems than the controls in working memory in everyday life but not in inhibition and shifting. No sex differences could be detected either in cognitive or behavioral aspects of executive functions. To conclude, cognitive and behavioral measures of executive functions were not congruent in VPT/VLBW children. In clinical practice, the combination of cognitive and behavioral instruments is required to disclose children’s executive difficulties.

Lateralization of cognitive functions after stroke in childhood

Rationale: A childs brain shows a remarkable ability to recover from adverse events such as stroke. Language functions recover particularly well, while visuo-spatial skills are more affected by brain damage, regardless of its localization. This study investigated the lateralization of language and visual search after childhood stroke. Methods: Ten patients with unilateral stroke (aged 10–19 years, five left-, five right-sided lesion) and 20 healthy controls (aged 8–20 years) completed a neuropsychological test battery and functional magnetic resonance imaging (fMRI) intended to activate predominantly right (visual search) and left-sided functional networks (language). Results: After stroke, patients demonstrated atypical lateralization of visual search functions (8/10 patients, left lateralization) more often than that of language (4/10 patients, right lateralization). There was a dissociation between the lateralization of productive and semantic language (4/10 patients, 1/20 controls) and between the lateralization of simple and complex visual search (3/10 patients, 3/20 controls). In patients, atypical contralateral activations occurred in the same areas that showed decreasing activation during development in healthy participants. Conclusion: The lateralization of functions depends upon the cognitive function measured. Dissociation between the lateralization of different language or visual search tasks can occur.

Age, Sex, and Performance Influence the Visuospatial Working Memory Network in Childhood

This study describes the influence of age, sex, and working memory (WM) performance on the visuospatial WM network. Thirty-nine healthy children (7–12 years) completed a dot location functional magnetic resonance imaging (fMRI) task. Percent signal change measured the intensity and laterality indices measured the asymmetry of activation in frontal and parietal brain regions. Old children showed greater intensity of activation in parietal regions than young children but no differences in lateralization were observed. Intensity of activation was similar across sex and WM performance groups. Girls and high WM performers showed more right-sided lateralization of parietal regions than boys and low WM performers.

Delay of cortical thinning in very preterm born children

BACKGROUND Cortical gray matter thinning occurs during childhood due to pruning of inefficient synaptic connections and an increase in myelination. Preterms show alterations in brain structure, with prolonged maturation of the frontal lobes, smaller cortical volumes and reduced white matter volume. These findings give rise to the question if there is a differential influence of age on cortical thinning in preterms compared to controls. AIMS To investigate the relationship between age and cortical thinning in school-aged preterms compared to controls. STUDY DESIGN AND OUTCOME MEASURES The automated surface reconstruction software FreeSurfer was applied to obtain measurements of cortical thickness based on T1-weighted MRI images. SUBJECTS Forty-one preterms (<32weeks gestational age and/or <1500g birth weight) and 30 controls were included in the study (7-12years). RESULTS In preterms, age correlated negatively with cortical thickness in right frontal, parietal and inferior temporal regions. Furthermore, young preterms showed a thicker cortex compared to old preterms in bilateral frontal, parietal and temporal regions. In controls, age was not associated with cortical thickness. CONCLUSION In preterms, cortical thinning still seems to occur between the age of 7 and 12years, mainly in frontal and parietal areas whereas in controls, a substantial part of cortical thinning appears to be completed before they reach the age of 7years. These data indicate slower cortical thinning in preterms than in controls.

Delayed development of neural language organization in very preterm born children.

This study investigates neural language organization in very preterm born children compared to control children and examines the relationship between language organization, age, and language performance. Fifty-six preterms and 38 controls (7–12 y) completed a functional magnetic resonance imaging language task. Lateralization and signal change were computed for language-relevant brain regions. Younger preterms showed a bilateral language network whereas older preterms revealed left-sided language organization. No age-related differences in language organization were observed in controls. Results indicate that preterms maintain atypical bilateral language organization longer than term born controls. This might reflect a delay of neural language organization due to very premature birth.

Cognitive and emotional effects of carotid stenosis.

PRINCIPLES Patients with carotid artery stenosis (CAS) are at risk of ipsilateral stroke and chronic compromise of cerebral blood flow. It is under debate whether the hypo-perfusion or embolism in CAS is directly related to cognitive impairment. Alternatively, CAS may be a marker for underlying risk factors, which themselves influence cognition. We aimed to determine cognitive performance level and the emotional state of patients with CAS. We hypothesised that patients with high grade stenosis, bilateral stenosis, symptomatic patients and/or those with relevant risk factors would suffer impairment of their cognitive performance and emotional state. METHODS A total of 68 patients with CAS of ≥70% were included in a prospective exploratory study design. All patients underwent structured assessment of executive functions, language, verbal and visual memory, motor speed, anxiety and depression. RESULTS Significantly more patients with CAS showed cognitive impairments (executive functions, word production, verbal and visual memory, motor speed) and anxiety than expected in a normative sample. Bilateral and symptomatic stenosis was associated with slower processing speed. Cognitive performance and anxiety level were not influenced by the side and the degree of stenosis or the presence of collaterals. Factors associated with less cognitive impairment included higher education level, female gender, ambidexterity and treated hypercholesterolemia. CONCLUSIONS Cognitive impairment and increased level of anxiety are frequent in patients with carotid stenosis. The lack of a correlation between cognitive functioning and degree of stenosis or the presence of collaterals, challenges the view that CAS per se leads to cognitive impairment.