Longitudinal data of neuropsychological profile in a cohort of Duchenne muscular dystrophy boys without cognitive impairment.

The aim of the study was to re-assess neuropsychological profile in a group of boys with Duchenne muscular dystrophy without intellectual disability and neuropsychiatric disorder three years apart from a previous evaluation, to establish possible changes over time. We were also interested in defining more in detail correlation between genotype and neuropsychological phenotype. Thirty-three of the previous 40 subjects (mean age at follow up: 10 years and 7 months) agreed to participate in the follow up study and to perform the new assessment. The results confirm a typical neuropsychological profile, with difficulty in the manipulation of stored information, poor abstract reasoning and planning capacity and impulsiveness, supporting the involvement of a cerebellar striatal cortical network for these children. The more detailed description of subgroups of subjects, according to the real expression of Dp140, let to reveal possible genotype-neuropsychological phenotype correlations, and a more general neuropsychological impairment emerged in boys without Dp140 expression.

Cognitive profile in Duchenne muscular dystrophy boys without intellectual disability: The role of executive functions.

The aim of our prospective observational study was to assess profiles of cognitive function and a possible impairment of executive functions in a cohort of boys with Duchenne muscular dystrophy without intellectual and behavior disability. Forty Duchenne boys (range of age: 6 years to 11 years and 6 months) were assessed by Wechsler Intelligence scale and battery of tests including tasks assessing working memory and executive functions (inhibition and switching, problem solving and planning). In our cohort some aspects of cognitive function were often impaired. These included multitasking, problem solving, inhibition and working memory necessary to plan and direct goal oriented behavior. Our results support the suggestion that aspects of cognitive function could be impaired even in boys without intellectual disability and support the hypothesis that executive functions may play an important role in specific aspects of cognitive impairment in Duchenne muscular dystrophy.

Widespread Focal Cortical Alterations in Autism Spectrum Disorder with Intellectual Disability Detected by Threshold-Free Cluster Enhancement.

BACKGROUND AND PURPOSE: In the past decades, a large body of work aimed at investigating brain structural anomalies accrued in autism spectrum disorder. Autism spectrum disorder is associated with intellectual disability in up to 50% of cases. However, only a few neuroimaging studies were conducted in autism spectrum disorder with intellectual disability, and none of them benefited from a nonsyndromic intellectual disability control group. MATERIALS AND METHODS: We performed a voxelwise investigation of the structural alterations in 25 children with autism spectrum disorder with intellectual disability by comparing them with 25 typically developing children and 25 nonsyndromic children with an intellectual disability. Besides a classic voxel-based morphometry statistical approach, the threshold-free cluster enhancement statistical approach was adopted. RESULTS: Classic voxel-based morphometry results did not survive family-wise error correction. The threshold-free cluster enhancement-based analysis corrected for family-wise error highlighted the following: 1) widespread focal cortical anomalies and corpus callosum alteration detected in autism spectrum disorder with intellectual disability; 2) basal ganglia and basal forebrain alteration detected both in autism spectrum disorder with intellectual disability and in nonsyndromic intellectual disability; and 3) differences in the frontocingulate-parietal cortex between autism spectrum disorder with intellectual disability and nonsyndromic intellectual disability. CONCLUSIONS: The present study suggests that the frontocingulate-parietal cortex may be the eligible key region for further investigations aiming at detecting imaging biomarkers in autism spectrum disorder with intellectual disability. The detection of structural alterations in neurodevelopmental disorders may be dramatically improved by using a threshold-free cluster enhancement statistical approach.

Basal forebrain involvement in low-functioning autistic children: a voxel-based morphometry study.

BACKGROUND AND PURPOSE: Imaging studies have revealed brain abnormalities in the regions involved in functions impaired in ASD (social relations, verbal and nonverbal communication, and adaptive behavior). We performed a VBM whole-brain analysis to assess the areas involved in autistic children with DD. MATERIALS AND METHODS: Twenty-one developmentally delayed children with ASD (aged 3-10 years) were compared with 21 controls matched for age, sex, and sociocultural background. All ASD cases had been diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria, with the Autism Diagnostic Observation Schedule-Generic, and the Autism Diagnostic Interview-Revised. The VBM data, covaried with intelligence quotient, age, and brain volume, were analyzed. RESULTS: ASD patients showed a pattern of regional GM reduction symmetrically affecting the basal forebrain, accumbens nucleus, cerebellar hemispheres, and perisylvian regions, including insula and putamen. Asymmetric involvement of GM was observed in other brain regions functionally connected to the basal forebrain, ie, an area located close to the medial and ventral surface of the frontal lobe. No regional WM differences were observed between the 2 groups. No significant differences between patients and controls were found regarding total brain volume, GM, and WM. CONCLUSIONS: In children with ASD and DD, the novel finding of our VBM study was the demonstration of reduced GM volume in the basal forebrain and the areas connected with it. This system is involved in social behavior, communication, and cognitive skills. Whether the involvement of the basal forebrain is characteristic of ASD or is related to the DD present in our patients needs further investigation.

Cognitive and behavioural effects of migraine in childhood and adolescence.

Since cognitive and behavioural characteristics of paediatric migraine sufferers have yet to be adequately defined, in this study we assessed the effect of migraine on the interictal functioning of children and adolescents by comparing the performance of two patient groups, 17 migraine sufferers with aura (MA) and 31 without aura (MoA) and by correlating the duration of the disorder, the frequency of attacks and interictal period with neuropsychological and behavioural findings. Both patient groups had cognitive performance within normal range except for a significant delay in the reaction time (RT) task. Both MA and MoA revealed a behavioural phenotype characterized by internalizing problems on Child Behaviour Check List (CBCL) scales. Slower RT to simple visual stimuli may be an early sign of a subclinical neuropsychological dysfunction, significantly correlated with the frequency of headache attacks and interictal period. The lack of a control group and other methodological limitations, such as patient selection bias and unadjusted P-value for multiple testing, make it difficult to give this finding a clearcut meaning. Further studies are needed on larger samples compared with a control group.

Unilateral frontal lobe epilepsy affects executive functions in children.

Very few studies to date have investigated the neuropsychological changes detectable in children suffering from frontal lobe epilepsy (FLE). The aim of the present study was to assess the effects of FLE on cognitive and executive functions in childhood. The sample includes 17 children with a frontal epileptogenic focus (10 right and 7 left), with no evidence of anatomical brain damage. These subjects were assessed by means of a battery of tests to investigate executive functioning. The results emphasised the presence of selective impairments of frontal lobe functions without evidence of deficits in global intellectual functioning. No side-specific deficits were detected, while an earlier onset of epilepsy and the duration of the disorder, but not the seizures frequency, were found to correspond with more severe deficits in some specific frontal lobe functions.

Intrathecal methotrexate affects cognitive function in children with medulloblastoma.

BACKGROUND: Cognitive impairment occurs after malignant brain tumor treatment in children, following brain radiotherapy and systemic and intrathecal chemotherapy. OBJECTIVES: 1) To compare two groups of children who underwent surgery for cerebellar medulloblastoma with their cousins and siblings, assessing intelligence, executive function, attention, visual perception, and short-term memory. Both groups were treated with the same combined radiotherapy-chemotherapy, but differed in that only one group received intrathecal methotrexate (MTX+). 2) To relate these measures to MRI findings (leukomalacia). RESULTS: The two groups performed worse than their control subjects in all tests. The MTX+ group younger than 10 years performed significantly worse in all tests, particularly executive ones. The group older than 10 years performed significantly worse only in short-term memory. Younger patients without MTX performed significantly worse than controls only in some neuropsychological measures; there were no differences between older patients and control subjects. Only in the MTX+ group was there a direct correlation between extent of leukomalacia and performance in some tests. CONCLUSIONS: The administration of intrathecal methotrexate to children with medulloblastoma worsens the cognitive deficits induced by chemotherapy and radiotherapy. The use of intrathecal methotrexate in the treatment of medulloblastoma and other malignancies should be reassessed.

Developmental patterns of verbal and visuospatial spans.

This study presents developmental data for verbal and spatial memory tasks: Corsi's block-tapping test and Luria's verbal learning test. Norms have been collected from 275 primary and early secondary school children aged from 5 years, 4 months to 13 years, 6 months. Our results confirm a slow and constant improvement in performances over time, and the advantage of about 1.5 items of the verbal span over the spatial span supports the existence of developmental differences between separate memory systems. No significant sex difference was found even if a slight trend in verbal span favouring female subjects is present.