While the cerebellum's role in motor function is well recognized, the nature of its concurrent role in cognitive function remains considerably less clear. The current consensus paper gathers diverse views on a variety of important roles played by the cerebellum across a range of cognitive and emotional functions. This paper considers the cerebellum in relation to neurocognitive development, language function, working memory, executive function, and the development of cerebellar internal control models and reflects upon some of the ways in which better understanding the cerebellum's status as a “supervised learning machine” can enrich our ability to understand human function and adaptation. As all contributors agree that the cerebellum plays a role in cognition, there is also an agreement that this conclusion remains highly inferential. Many conclusions about the role of the cerebellum in cognition originate from applying known information about cerebellar contributions to the coordination and quality of movement. These inferences are based on the uniformity of the cerebellum's compositional infrastructure and its apparent modular organization. There is considerable support for this view, based upon observations of patients with pathology within the cerebellum.

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Joubert syndrome (JS) is a recessive neurodevelopmental disorder defined by a characteristic cerebellar and brainstem malformation recognizable on axial brain magnetic resonance imaging as the "Molar Tooth Sign". Although defined by the neurological features, JS is associated with clinical features affecting many other organ systems, particularly progressive involvement of the retina, kidney, and liver. JS is a rare condition; therefore, many affected individuals may not have easy access to subspecialty providers familiar with JS (e.g., geneticists, neurologists, developmental pediatricians, ophthalmologists, nephrologists, hepatologists, psychiatrists, therapists, and educators). Expert recommendations can enable practitioners of all types to provide quality care to individuals with JS and know when to refer for subspecialty care. This need will only increase as precision treatments targeting specific genetic causes of JS emerge. The goal of these recommendations is to provide a resource for general practitioners, subspecialists, and families to maximize the health of individuals with JS throughout the lifespan.

Voxel-based morphometry (VBM) studies have reported abnormalities in brain regions involved in functions that are commonly impaired in autism spectrum disorders (ASD). However, little is known about brain structure anomalies in low-functioning (LF) young children with ASD. A VBM analysis was carried out to assess brain regions involved in ASD LF children, and a multiple regression analysis was used to examine the relationship between regional volume changes and autism symptom measures. Twenty-six LF ASD children (2-10 years) were compared with 21 controls. A VBM-Diffeomorphic Anatomical Registration analysis using Exponentiated Lie algebra (DARTEL) was used to evaluate gray matter (GM) and white matter alterations, covaried with Intelligence Quotient, age, and total brain volume. The resulting altered regions were correlated with Autism Diagnostic Interview (ADI)-Revised and Autism Diagnostic Observation Schedule (ADOS)-Generic scores. GM bilateral reduction was noted in the cerebellum (Crus II and vermis) and in the hippocampi in ASD group. GM reduction was also detected in the inferior and superior frontal gyri, in the occipital medial and superior gyri, and in the inferior temporal gyrus of the left cerebral hemisphere. In the right hemisphere, GM reduction was found in the post-central cortex and in the occipital inferior gyrus. Multiple regression analysis showed a correlation between alterations in GM volume in the cerebellum (Crus II and vermis) and ADI-communication and ADOS-total (communication and interaction) scores. These findings seem to confirm that the cerebellum is involved in integrating and regulating emotional and cognitive functions which are impaired in ASD.

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.

Although relations between the extent of periventricular leukomalacia and neuropsychological performance in preterm children with spastic diplegia have been extensively investigated, studies on term children with spastic diplegia are rare. The authors examined 15 preterm children and 9 term children with spastic diplegia, all of whom had periventricular leukomalacia as a main magnetic resonance imaging (MRI) finding (excluding full-term spastic diplegic children with other MRI findings). Cognitive abilities (Griffith scale) and visuoperceptual abilities (Developmental Test of Visual Perception) were compared in the 2 groups and related to periventricular leukomalacia severity. Cognitive performance was substantially similar in the 2 groups. However, the overall Developmental Test of Visual Perception scores were below normal in the preterm and were normal in the term children; furthermore, visuoperceptual abilities were differentially affected in the preterm children, with visuomotor abilities more compromised than nonmotor visuoperceptual abilities. These children had similar cognitive performance and MRI findings, so the greater visuoperceptual compromise in the preterm group suggests a direct influence of prematurity, which may have adversely influenced the reorganization of visual centers and pathways following the initial developmental insult. The strabismus present in most preterm children would also have contributed to their greater visuoperceptual compromise. The authors conclude that the management of preterm and term children should differ, with concentration on visuoperceptual skills and rehabilitation in the former.

Most published neuropsychologic studies on frontal lobe epilepsy have been performed on mixed groups of adults and adolescents with epilepsies of varying etiology. The cognitive profile of frontal lobe epilepsy in children has not been defined. The purpose of this study was to assess neuropsychologic performance in children with frontal lobe epilepsy. Intelligence and executive functions were examined in eight children (age 6 7/12 years to 13 11/12 years) with frontal lobe epilepsy. Performance was related to the focus side, seizure frequency, and age of epilepsy onset. Frontal lobe epilepsy was associated with a range of frontal dysfunctions, but IQ was generally spared. Left focus was associated with deficits in categorization, verbal long-term memory, and detailed visuospatial analysis. Frequent seizures correlated with attention difficulties and inability to inhibit impulsive responses. Children whose epilepsy appeared before age 6 years had reduced ability to change behavioral strategies. Frontal epileptic activity alone can cause selective frontal deficits, the severity and nature of which are related to side, seizure frequency, and age of epilepsy onset. These findings require confirmation on larger series of selected children.

Microarray-based comparative genomic hybridization is a method of molecular analysis that identifies chromosomal anomalies (or copy number variants) that correlate with clinical phenotypes. The aim of the present study was to apply a clinical score previously designated by de Vries to 329 patients with intellectual disability/developmental disorder (intellectual disability/developmental delay) referred to our tertiary center and to see whether the clinical factors are associated with a positive outcome of aCGH analyses. Another goal was to test the association between a positive microarray-based comparative genomic hybridization result and the severity of intellectual disability/developmental delay. Microarray-based comparative genomic hybridization identified structural chromosomal alterations responsible for the intellectual disability/developmental delay phenotype in 16% of our sample. Our study showed that causative copy number variants are frequently found even in cases of mild intellectual disability (30.77%). We want to emphasize the need to conduct microarray-based comparative genomic hybridization on all individuals with intellectual disability/developmental delay, regardless of the severity, because the degree of intellectual disability/developmental delay does not predict the diagnostic yield of microarray-based comparative genomic hybridization.