Bernard Dan

• Professor at Université Libre de Bruxelles

Patients with Duchenne muscular dystrophy (DMD) commonly show specific cognitive deficits in addition to a severe muscle impairment caused by the absence of dystrophin expression in skeletal muscle. These cognitive deficits have been related to the absence of dystrophin in specific regions of the central nervous system, notably cerebellar Purkinje...

This study aimed to explore the effects of a four-week intensive eye-tracking intervention on children with dyskinetic cerebral palsy (DCP), focusing on goal attainment, communication competencies, stress levels, subjective workload, and caregivers’ perception of psychosocial impact. A multiple case study design with non-concurrent, staggered multi...

Aim: To report on the prevalence, neuroimaging patterns, and function of children with cerebral palsy (CP) in Belgium for birth years 2007-2012, and identify distinctive risk indicators and differences in outcome between CP subtypes. Methods: Antenatal and perinatal/neonatal factors, motor and speech function, associated impairments, and neuroim...

This study investigated the reliability of 3‐dimensional freehand ultrasound (3DfUS) to quantify the size (muscle volume [MV] and anatomical cross‐sectional area [aCSA]), length (muscle length [ML], tendon length [TL], and muscle tendon unit length [MTUL]), and echo‐intensity (EI, whole muscle and 50% aCSA), of lower limb muscles in children with s...

Cerebral palsy is a lifelong neurodevelopmental condition arising from non-progressive disorders occurring in the fetal or infant brain. Cerebral palsy has long been categorised into discrete motor types based on the predominance of spasticity, dyskinesia, or ataxia. However, these motor disorders, muscle weakness, hypotonia, and impaired selective...

Aim To synthesize existing evidence on the effectiveness of speech‐language teleinterventions delivered via videoconferencing to users of augmentative and alternative communication (AAC) devices. Method A systematic literature search was conducted in 10 electronic databases, from inception until August 2021. Included were speech‐language teleinter...

Aim This study aimed to explore eye movements and stress during eye‐tracking gaming performance in children with dyskinetic cerebral palsy (CP) compared with typically developing children, and associations between eye‐tracking performance, eye movements, stress, and participants' characteristics. Method This cohort study included 12 children with...

Previous studies showed reduced activity of anterior cingulate cortex and supplementary motor area during inhibition in children with attention‐deficit/hyperactivity disorder (ADHD). This study aimed to investigate deep brain generators underlying alterations of evoked potentials components triggered by visual GO/NoGO tasks in children with ADHD co...

We report a 50-year-old man with celiac disease who presented with occipital epilepsy. Brain MRI showed right occipital subcortical white matter hyperintensities, consistent with the posterior epileptic focus suggested by the clinical features of the seizures and documented on EEG. Shortly after the introduction of gluten free diet the white matter...

Objectives To investigate the operational competences screen navigation and dwell function underlying eye gaze performance, and the relation of dystonia and choreoathetosis with eye gaze performance in children with dyskinetic cerebral palsy (DCP). Methods During a 5-week intervention, ten participants with DCP played eye gaze video games daily fo...

Aim To assess test–retest reliability of the Dyskinesia Impairment Scale (DIS) in children and young adults with dyskinetic cerebral palsy (CP). Method Dystonia and choreoathetosis were assessed in 15 participants with dyskinetic CP (13 males, 2 females; age range 5–22y, mean 14y, SD 4y) using the DIS in two separate sessions over 7 days. Exclusio...

Polymicrogyria (PMG) is a heterogeneous brain malformation that may result from prenatal vascular disruption or infection, or from numerous genetic causes that still remain difficult to identify. We identified three unrelated patients with polymicrogyria and duplications of chromosome 2p, defined the smallest region of overlap, and performed gene p...

We describe a 33-year-old woman with chronic bulbar dysarthria after ischemic brainstem stroke who underwent a new form of constraint-induced therapy, namely constraint-induced dysarthria therapy, based on three principles: avoidance of supportive devices, intensive therapy, and gradually augmenting difficulty. After a 2-month intervention, improve...

Purkinje cells (PC) control deep cerebellar nuclei (DCN), which in turn inhibit inferior olive nucleus, closing a positive feedback loop via climbing fibers. PC highly express potassium BK channels but their contribution to the olivo-cerebellar loop is not clear. Using multiple-unit recordings in alert mice we found in that selective deletion of BK...

In contrast to childhood ADHD that is characterized by inattention, impulsivity and hyperactivity, most adults with ADHD predominantly exhibit inattention. We used a new oddball paradigm using implicit navigational images and analysed EEG dynamics with swLORETA inverse modelling of the evoked potential generators to study cortical processing in adu...

Background: Studies investigating event-related potential (ERP) evoked in a Cue-Go/NoGo paradigm have shown lower frontal N1, N2 and central P3 in children with attention-deficit/hyperactivity disorder (ADHD) compared to typically developing children (TDC). However, the electroencephalographic (EEG) dynamics underlying these ERPs remain largely une...

Introduction Preterm and very low birthweight infants are at increased risk for neurodevelopmental disorders, including cerebral palsy, sensory impairment and intellectual disability. Several early intervention approaches have been designed in the hope of optimising neurological development in this context. It seems important that the intervention...

Cerebral palsy is the most frequent cause of severe physical disability in childhood. Dyskinetic cerebral palsy (DCP) is the second most common type of cerebral palsy after spastic forms. DCP is typically caused by non-progressive lesions to the basal ganglia or thalamus, or both, and is characterised by abnormal postures or movements associated wi...

The ecological environment offered by virtual reality is primarily supported by visual information. The different image contents and their rhythmic presentation imply specific bottom-up and top-down processing. Because these processes already occur during passive observation we studied the brain responses evoked by the presentation of specific 3D v...

Brain function is compromised in myotonic dystrophy type 1 (DM1), but the underlying mechanisms are not fully understood. To gain insight into the cellular and molecular pathways primarily affected, we studied a mouse model of DM1 and brains of adult patients. We found pronounced RNA toxicity in the Bergmann glia of the cerebellum, in association w...

Background and purpose: To support clinical decision-making in central neurological disorders, a physical examination is used to assess responses to passive muscle stretch. However, what exactly is being assessed is expressed and interpreted in different ways. A clear diagnostic framework is lacking. Therefore, the aim was to arrive at unambiguous...

Human brain adaptation in weightlessness follows the necessity to reshape the dynamic integration of the neural information acquired in the new environment. This basic aspect was here studied by the electroencephalogram (EEG) dynamics where oscillatory modulations were measured during a visuo-attentional state preceding a visuo-motor docking task....

Aim: To relate dystonia and choreoathetosis with activity, participation and quality of life (QOL) in children and youth with dyskinetic Cerebral Palsy (CP). Methods: Fifty-four participants with dyskinetic CP (mean age 14y6m, SD 4y2m, range 6-22y) were included. The Dyskinesia Impairment Scale (DIS) was used to evaluate dystonia and choreoathet...

Background: Children with cerebral palsy show dysfunctional postural control which interferes with their functional performance and daily-life activities. Objective: The aim of the study was to identify the effect of a 3D supporting garment on trunk postural control and interjoint coordination during gait in children with bilateral cerebral pals...

Background Optimal stimulation theory and moderate brain arousal (MBA) model hypothesize that extra-task stimulation (e.g. white noise) could improve cognitive functions of children with attention-deficit/hyperactivity disorder (ADHD). We investigate benefits of white noise on attention and inhibition in children with and without ADHD (7–12 years o...

Brain dynamics is at the basis of top performance accomplishment in sports. The search for neural biomarkers of performance remains a challenge in movement science and sport psychology. The non-invasive nature of high-density electroencephalography (EEG) recording has made it a most promising avenue for providing quantitative feedback to practition...

Cerebral palsy is the most common cause of childhood-onset, lifelong physical disability in most countries, affecting about 1 in 500 neonates with an estimated prevalence of 17 million people worldwide. Cerebral palsy is not a disease entity in the traditional sense but a clinical description of children who share features of a non-progressive brai...

In order to characterize the neural signature of a motor imagery (MI) task, the present study investigates for the first time the oscillation characteristics including both of the time-frequency measurements, event related spectral perturbation and intertrial coherence (ITC) underlying the variations in the temporal measurements (event related pote...

Preventable risk factors for sudden infant death syndrome include the infant's environment and response characteristics. Various infant and environmental factors thus modify the vital cardiocirculatory, respiratory and arousal controls in healthy infants. Similar changes in cardiorespiratory and autoresuscitative responses have been found in the an...

Forty years ago, a consensual definition of the cerebral palsy concept was suggested, delineating it as a disorder of movement and posture secondary to non-progressive pathological processes that affect the immature brain. Because this concept is pragmatic and based on function, it has survived unaltered many changes in pathophysiolgical knowledge,...

Background: Children born preterm are at risk for developmental cerebral visual impairment. Several modalities of visual evoked potentials recording have been used to approach prognosis. The recent development of high-density EEG protocols allows evaluation of the oscillatory content of cortical activities evoked by specific stimulation. We aimed t...

Background: Angelman syndrome is a genetic neurodevelopmental disorder recognised to show characteristic (non-epileptic) high-amplitude slow rhythmic electroencephalographic patterns. These hypersynchronous neuronal activities have been studied to approach the pathophysiology of the condition. Aim: to analyse these patterns with enhanced recording...

Paracetamol (acetaminophen) remains the first line for the treatment of pain and fever in pregnancy. Recently published epidemiological studies suggested a possible association between paracetamol exposure in utero and attention-deficit-hyperactivity disorder/hyperkinetic disorder (ADHD/HKD) or adverse development issues in children. However, the e...

Careful study of the phenotype can have implications at several levels, namely clinical diagnosis, pathophysiological reasoning, management planning, and outcome measurement. Behavioural phenotypes involve cognition, communication, social skills, and motor control. They can be documented in a host of neurodevelopmental conditions and approached wit...

Efforts to document early changes in the developing brain have resulted in the construction of increasingly accurate structural images based on magnetic resonance imaging (MRI) in newborn infants. Tractography diagrams obtained through diffusion tensor imaging have focused on white matter microstructure, with particular emphasis on neuronal connect...

The highly stereotyped, crystal-like architecture of the cerebellum has long served as a basis for hypotheses with regard to the function(s) that it subserves. Historically, most clinical observations and experimental work have focused on the involvement of the cerebellum in motor control, with particular emphasis on coordination and learning. Two...

Angelman syndrome (AS) is a genetic neurodevelopmental disorder in which cerebellar functioning impairment has been documented despite the absence of gross structural abnormalities. Characteristically, a spontaneous 160 Hz oscillation emerges in the Purkinje cells network of the Ube3a (m-/p+) Angelman mouse model. This abnormal oscillation is induc...

Autosomal recessive forms of Charcot-Marie-Tooth disease (ARCMT) are rare but severe disorders of the peripheral nervous system. Their molecular basis is poorly understood due to the extensive genetic and clinical heterogeneity, posing considerable challenges for patients, physicians, and researchers. We report on the genetic findings from a system...

Biological motion observation has been recognized to produce dynamic change in sensorimotor activation according to the observed kinematics. Physical plausibility of the spatial-kinematic relationship of human movement may play a major role in the top-down processing of human motion recognition. Here, we investigated the time course of scalp activa...

In this study we employed a dynamic recurrent neural network (DRNN) in a novel fashion to reveal characteristics of control modules underlying the generation of muscle activations when drawing figures with the outstretched arm. We asked healthy human subjects to perform four different figure-eight movements in each of two workspaces (frontal plane...

Owing to excellent time resolution and optimized spatial resolution related to increased number of recording electrodes, high-density electroencephalography allows localization of the sources of cortical activities evoked by specific stimulation. Here we evaluate the feasibility of a high-density EEG mismatch negativity of event-related potentials...

Background: Although there is increasing recognition of the role of somatic mutations in genetic disorders, the prevalence of somatic mutations in neurodevelopmental disease and the optimal techniques to detect somatic mosaicism have not been systematically evaluated. Methods: Using a customized panel of known and candidate genes associated with...

Background: The continuation of binge drinking is associated with the development of neurocognitive brain abnormalities similar to those observed in patients with alcohol dependence. Alcohol cue reactivity constitutes a risk marker for alcohol dependence. Through event-related potentials (ERPs), we aimed to examine its potential presence as well a...

Children with attention deficit/hyperactivity disorder (ADHD) have been found to show theta-beta correlation in rhythmic brain oscillations. We aimed to further analyse scalp activity in order to study global amplitude of activation and topographical stability during a visual-cued task in children with ADHD. Participants and methods: Fourteen ADHD...

Angelman syndrome(AS)is a neurogenetic disorder with well-described developmental and behavioural features. Its biophenotype includes rhythmic EEG abnormalities described according to their main frequency and topography. Pattern I is classically reported as runs of frontal high-amplitude (>200-300μV) 2-3/s (delta) activity, and Pattern II as prolon...

Non-convulsive status epilepticus is often challenging in paediatric practice. It is a treatable cause of cognitive deterioration and behavioural disturbances in many neurological conditions. It has a high association with Angelman syndrome, where differential electrodiagnosis with the typical non-epileptic rhythmic EEG patterns may be difficult. I...

Infant botulism is a rare neuroparalytic disease caused by the neurotoxin of Clostridium botulinum. Initial clinical features are constipation, poor feeding, descending hypotonia, drooling, irritability, weak crying and cranial nerve dysfunctions. We describe the clinical progression and the epidemiological investigation carried out in a 3-month-ol...

Infant botulism is a rare neuroparalytic disease caused by the neurotoxin of Clostridium botulinum. Initial clinical features are constipation, poor feeding, descending hypotonia, drooling, irritability, weak crying and cranial nerve dysfunctions. We describe the clinical progression and the epidemiological investigation carried out in a 3-month-ol...

In this review, we discuss sleep recording techniques, normal sleep characteristics, and the effects of sleep deprivation. Sleep quality and quantity mature with development. Sleep-wake behaviors are described in fetuses, infants, preschool, and school-age children and adolescents. The short-term and medium-term effects of sleep deprivation are rev...

In this review, we discuss the effects of noise on sleep characteristics of fetuses, infants, children, and adolescents. Noise disturbance during sleep at these developmental periods may have health and/or educational implications; the disturbances may be common and are amenable to investigation. The effects of noise on sleep and awakening from sle...

The N30 component of the somatosensory evoked potential is known to be modulated by sensory interference, motor action, movement ideation and observation. We introduce a new paradigm in which the observation task of another person's hand movement triggers the somatosensory stimulus, inducing the N30 response in participants. In order to identify th...

AimThe first aim of this study was to systematically review and critically assess manually controlled instrumented spasticity assessment methods that combine multidimensional signals. The second aim was to extract a set of quantified parameters that are psychometrically sound to assess spasticity in a clinical setting.Method Electronic databases we...

Purkinje cell (PC) firing represents the sole output from the cerebellar cortex onto the deep cerebellar and vestibular nuclei. Here, we explored the different modes of PC firing in alert mice by extracellular recording. We confirm the existence of a tonic and/or bursting and quiescent modes corresponding to UP and DOWN state, respectively. We demo...

Visual perception is not only based on incoming visual signals but also on information about a multimodal reference frame that incorporates vestibulo-proprioceptive input and motor signals. In addition, top-down modulation of visual processing has previously been demonstrated during cognitive operations including selective attention and working mem...

A central question in Neuroscience is that of how the nervous system generates the spatiotemporal commands needed to realize complex gestures, such as handwriting. A key postulate is that the CNS builds up complex movements from a set of simpler motor primitives or control modules. In this study we examined the control modules underlying the genera...

The practice of pediatric neurology demands a high level of responsibility at multiple levels. These include listening carefully to people's stories in order to assess each situation, planning and implementing investigations and therapies, individual and family counseling, longitudinal follow-up from fetal life throughout childhood and adolescence,...

It has been recently demonstrated that cerebellar long-term depression (LTD), an interaction between the parallel fibers (PF) and Purkinje cells (PCs) that requires the combined activation of the parallel and climbing fibers, can be induced in the cerebellum of alert mice in response to sensory peripheral input. Ca2+ signalling has been proposed to...

The physiological relevance of discrete neuronal states of the cerebellar cortex, namely up-and down-states has been increasingly recognized. Here we explored by extracellular recording the different modes of PC firing in alert mice. We confirm the existence of a tonic and/or bursting and quiescent modes corresponding to the up-and down-state, resp...

Over the past decades, it has become clear that the most efficient way to prevent status epilepticus is to stop the seizure as fast as possible, and early treatment of prolonged convulsive seizures has become an integral part of the overall treatment strategy in epilepsy. Benzodiazepines are the first choice drugs to be used as emergency medication...

Background: Gender is increasingly recognized as an important influence on brain development, disease susceptibility, and response to pharmacologic and rehabilitative treatments. In re-generative medicine, it remains entirely unknown whether there is an interaction between transplanted stem cells and host gender that might bias efficacy and safety...

Poster

Identification and diagnosis of autism spectrum disorders is essentially based on behavioral presentation and developmental history. The current average age at diagnosis is older than 3 years. Over the past 15 years, there has been increasing documentation of the early signs of autism spectrum disorders through both individual retrospective parenta...

The existence of dedicated neuronal modules such as those organized in the cerebral cortex, thalamus, basal ganglia, cerebellum, or spinal cord raises the question of how these functional modules are coordinated for appropriate motor behavior. Study of human locomotion offers an interesting field for addressing this central question. The coordinati...

The musculoskeletal system (MSS) is essential to allow us performing every-day tasks, being able to have a professional life or developing social interactions with our entourage. MSS pathologies have a significant impact on our daily life. It is therefore not surprising to find MSS-related health problems at the top of global statistics on professi...

Bacterial meningitis (BM) remains a major global challenge. Globally, Hib, S. pneumoniae, and N. meningitidis cause about 90% of cases of BM beyond the neonatal period. After colonization of the upper respiratory tract by one of these pathogens, invasion occurs across the epithelium. Following entry into the bloodstream, bacteria survive through ev...

Diagnosis and most of all classification of children with cerebral palsy (CP) remain a challenge for clinicians. To help them in this process, clinicians can rely on several clinical testing procedures as well as complementary investigations. The goal of this study was to determine which clinical tests found in the literature are the most frequentl...

Botulinum toxin injections may significantly improve lower limb kinematics in gait of children with spastic forms of cerebral palsy. Here we aimed to analyze the effect of lower limb botulinum toxin injections on trunk postural control and lower limb intralimb (intersegmental) coordination in children with spastic diplegia or spastic hemiplegia (GM...

The role of cerebellar plasticity has been increasingly recognized in learning. The privileged relationship between the cerebellum and the inferior olive offers an ideal circuit for attempting to integrate the numerous evidences of neuronal plasticity into a translational perspective. The high learning capacity of the Purkinje cells specifically co...

Presentation

Rett syndrome is characterized by early neurological regression that severely affects motor, cognitive and communication skills, leading to microcephaly, a delay in acquiring new skills, absence of speech, emergence of autistic features, loss of purposeful manipulation skills, replaced by stereotyped hand movements, other motor abnormalities includ...

Most clinical tools for measuring spasticity, such as the Modified Ashworth Scale (MAS) and the Modified Tardieu Scale (MTS), are not sufficiently accurate or reliable. This study investigated the clinimetric properties of an instrumented spasticity assessment. Twenty-eight children with spastic cerebral palsy (CP) and 10 typically developing (TD)...

Background: The Dyskinesia Impairment Scale (DIS) is a new scale for measuring dystonia and choreoathetosis in dyskinetic Cerebral Palsy (CP). Previously, reliability of this scale has only been assessed for raters highly experienced in discriminating between dystonia and choreoathetosis. Aims: The aims of this study are to examine the reliabili...

Introduction: Ankle-foot orthoses may significantly improve lower limb kinematics in the gait of children with cerebral palsy. Here we aimed to analyze the effect of ankle-foot orthoses on trunk postural control and lower limb intersegmental coordination in children with mild spastic diplegia (GMFCS I or II). Methods: We recorded tridimensional...

Clinical expression of POLG mutations is largely variable. We present a patient with a new mutation in spacer region of mitochondrial polymerase gamma protein (P765T). The clinical picture is characterized by the presence of sensory-ataxic neuropathy, ophthalmoplegia, dysarthria and gastroparesis, which had not been previously observed in ataxia ne...