Pediatric Stroke: Unique Implications of the Immature Brain on Injury and Recovery

An Initial Psychometric Evaluation of a Novel Upper Extremity Pediatric Stroke Hemiplegic Motor Impairment Scale

BACKGROUND

Our team designed an innovative, observation-based motor impairment measure-the Pediatric Stroke Hemiplegic Motor Impairment Scale (Pedi HEMIs). Here we present the results of a survey describing common practices in the pediatric stroke community and the initial psychometric properties of the upper extremity subscale of the Pedi HEMIs (Pedi HEMIs-UE).

METHODS

This is a cross-sectional study whereby participants completed a battery of assessments including the novel Pedi HEMIs-UE. Internal consistency was measured via Cronbach alpha (α). Intraclass correlation (ICC) was used to assess inter-rater reliability (IRR). Concurrent validity was investigated using Pearson or polychoric correlations and simple linear regressions.

RESULTS

The study sample consisted of 18 children aged 1.08 to 15 years. Two participants completed two sets of evaluations, totaling 20 data sets. Cronbach α, a measure of internal consistency, was on average 0.91 (range: 0.89 to 0.92). IRR was excellent with the six raters in almost perfect agreement (ICC = 0.91; 95% confidence interval [CI]: 0.83 to 0.96). Pearson correlation coefficient between the Pedi HEMIs-UE and logit Assisting Hand Assessment (AHA)/mini-AHA was -0.938 (95% CI: -0.979 to -0.827, P < 0.001), indicating excellent concurrent validity.

CONCLUSIONS

We found excellent feasibility, reliability, and validity of the Pedi HEMIs-UE in a convenience sample of youth with hemiparesis after stroke.

A Review of Current Perspectives on Motoric Insufficiency Rehabilitation following Pediatric Stroke

Pediatric stroke (PS) is an injury caused by the occlusion or rupture of a blood vessel in the central nervous system (CNS) of children, before or after birth. Hemiparesis is the most common motoric deficit associated with PS in children. Therefore, it is important to emphasize that PS is a significant challenge for rehabilitation, especially since the consequences may also appear during the child's growth and development, reducing functional capacity. The plasticity of the child's CNS is an important predecessor of recovery, but disruption of the neural network, specific to an immature brain, can have harmful and potentially devastating consequences. In this review, we summarize the complexity of the consequences associated with PS and the possibilities and role of modern rehabilitation. An analysis of the current literature reveals that Constraint-Induced Movement Therapy, forced-use therapy, repetitive transcranial magnetic stimulation, functional electrical stimulation and robot-assisted therapy have demonstrated at least partial improvements in motor domains related to hemiparesis or hemiplegia caused by PS, but they are supported with different levels of evidence. Due to the lack of randomized controlled studies, the optimal rehabilitation treatment is still debatable, and therefore, most recommendations are primarily based on expert consensuses, opinions and an insufficient level of evidence.

[Surgical treatment of brain tumors adjacent to corticospinal tract in children]

An urgent problem in modern neurosurgery is resection of brain tumors adjacent to corticospinal tract (CST) due to high risk of its damage and subsequent disability. The main methods for prevention of intraoperative damage to CST are preoperative MR tractography and intraoperative electrophysiological monitoring. Both methods are used in pediatric neurosurgery. We reviewed the PubMed database since 2000 using the following keywords: «tumors of the hemispheres in children», «corticospinal tract», «MR tractography», «intraoperative electrophysiological monitoring». We present available literature data on preoperative MR tractography and intraoperative electrophysiological monitoring in children with supratentorial tumors near CST. Algorithm of intraoperative electrophysiological monitoring is often missing or insufficiently described. MR tractography is usually presented in case reports. Researchers do not compare the effectiveness of MR tractography and intraoperative electrophysiological monitoring. In case of MR tractography, a limitation is impossible CST reconstruction in children 2-3 years old. This may be due to unformed pyramidal system in these children.

CONCLUSION

Preoperative MR tractography and intraoperative electrophysiological monitoring are valid methods for assessment of CST. Optimal research parameters in children require careful study that will allow objective planning of each stage of preoperative management and increase resection quality for gliomas near CST in children without neurological deterioration.

Stroke in the Developing Brain: Neurophysiologic Implications of Stroke Timing, Location, and Comorbid Factors

BACKGROUND

Pediatric stroke, which is unique in that it represents a static insult to a developing brain, often leads to long-term neurological disability. Neuroplasticity in infants and children influences neurophysiologic recovery patterns after stroke; therefore outcomes depend on several factors including the timing and location of stroke and the presence of comorbid conditions.

METHODS

In this review, we discuss the unique implications of stroke occurring in the fetal, perinatal, and childhood/adolescent time periods. First, we highlight the impact of the developmental stage of the brain at the time of insult on the motor, sensory, cognitive, speech, and behavioral domains. Next, we consider the influence of location of stroke on the presence and severity of motor and nonmotor outcomes. Finally, we discuss the impact of associated conditions on long-term outcomes and risk for stroke recurrence.

RESULTS

Hemiparesis is common after stroke at any age, although the severity of impairment differs by age group. Risk of epilepsy is elevated in all age groups compared with those without stroke. Outcomes in other domains vary by age, although several studies suggest worse cognitive outcomes when stroke occurs in early childhood compared with fetal and later childhood epochs. Conditions such as congenital heart disease, sickle cell disease, and moyamoya increase the risk of stroke and leave patients differentially vulnerable to neurodevelopmental delay, stroke recurrence, silent infarcts, and cognitive impairment.

CONCLUSIONS

A comprehensive understanding of the interplay of various factors is essential in guiding the clinical care of patients with pediatric stroke.

Intra-arterial chemotherapy for retinoblastoma: Experience from the pediatric ophthalmology referral center in Malaysia with literature review

PURPOSE

We aimed to analyze our 4-year experience of intra-arterial chemotherapy (IAC) for retinoblastoma (RB) and to examine the tumor response, globe salvage, mortality, and safety profile of IAC in the Malaysian profile.

MATERIALS AND METHODS

This was a retrospective, interventional case series. A total of 22 eyes of 20 patients with RB who underwent IAC using melphalan and topotecan from January 2018 to December 2021 in Hospital Kuala Lumpur were retrospectively reviewed. Tumor response, globe salvage, mortality, and safety profile of IAC were compared based on the International Classification of Retinoblastoma.

RESULTS

The mean patient age at IAC was 21.3 months. An overall globe salvage rate of 63.6% was observed: more specifically, 100% for Group A, 75% for Groups B and C, 66.7% for Group D, and 42.9% for Group E. Poor tumor response after IAC was significantly associated with a lesser chance of globe salvage (P = 0.045). The overall rate of good tumor response following IAC was 77.3%. Specifically, rates of good tumor response in each group were 100%, 75%, 75%, 83.3% and 71.4% in group A, B, C, D and E, respectively. The mortality rate was 5%. Complications (per-catheterization) included cerebral infarct (2.2%), oxygen desaturation (2.2%), vomiting (26.1%), periorbital edema (8.8%), ptosis (6.5%), fever, femoral hematoma, and hyperpigmentation over lid (4.4% each).

CONCLUSION

Four-year experience showed that IAC is a safe and effective method for RB management. Patients with a poor response after IAC may have a lower chance of globe salvage. Careful patient selection is of utmost importance to achieve the best outcome in a setting of limited health-care resources.

Neuroimmune Support of Neuronal Regeneration and Neuroplasticity following Cerebral Ischemia in Juvenile Mice

Ischemic damage to the brain and loss of neurons contribute to functional disabilities in many stroke survivors. Recovery of neuroplasticity is critical to restoration of function and improved quality of life. Stroke and neurological deficits occur in both adults and children, and yet it is well documented that the developing brain has remarkable plasticity which promotes increased post-ischemic functional recovery compared with adults. However, the mechanisms underlying post-stroke recovery in the young brain have not been fully explored. We observed opposing responses to experimental cerebral ischemia in juvenile and adult mice, with substantial neural regeneration and enhanced neuroplasticity detected in the juvenile brain that was not found in adults. We demonstrate strikingly different stroke-induced neuroimmune responses that are deleterious in adults and protective in juveniles, supporting neural regeneration and plasticity. Understanding age-related differences in neuronal repair and regeneration, restoration of neural network function, and neuroimmune signaling in the stroke-injured brain may offer new insights for the development of novel therapeutic strategies for stroke rehabilitation.

Implications of age at lesion onset for neuropsychological outcomes: A systematic review focusing on focal brain lesions

Theories of the relation between age at lesion onset and outcomes posit different views of the young brain: resilient and plastic (i.e., the so-called "Kennard Principle"), or vulnerable (i.e., the Early Vulnerability Hypothesis). There is support for both perspectives in previous research and questions about the "best" or "worst" times to sustain brain injury remain. Here, we present a systematic review investigating the influence of age at focal brain lesion onset on cognitive functioning. This systematic review identifies and qualitatively synthesizes empirical studies from 1985 to 2021 that investigated age at lesion onset as a variable of interest associated with neuropsychological outcomes. A total of 45 studies were identified from PubMed, PsycINFO, and CINAHL databases. Almost all studies indicated that brain injury earlier in the developmental period predicts worse cognitive outcomes when compared to onset either later in the developmental period or in adulthood. More specifically, the overwhelming majority of studies support an "earlier is worse" model for domains of intellect, processing speed, attention and working memory, visuospatial and perceptual skills, and learning and memory. Relatively more variability in outcomes exists for domains of language and executive functioning. Outcomes for all domains are influenced by various other age and injury variables (e.g., lesion size, lesion laterality, chronicity, a history of epilepsy). Continued interdisciplinary understanding and communication about the influence of age at lesion onset on neuropsychological outcomes will aid in promoting the best possible outcomes for patients.

Language and Cognitive Outcomes Following Ischemic Stroke in Children With Monolingual and Bilingual Exposure

Aim: Although many children who experience ischemic stroke come from bilingual backgrounds, it is unclear whether bilingual exposure affects poststroke development. Our research evaluates bilingual and monolingual exposure on linguistic/cognitive development poststroke across 3 stroke-onset groups. Method: An institutional stroke registry and medical charts were used to gather data on 237 children across 3 stroke-onset groups: neonatal, <28 days; first-year, 28 days to 12 months; and childhood, 13 months to 18 years. The Pediatric Stroke Outcome Measure (PSOM), administered several times poststroke, was used to evaluate cognition and linguistic development. Results: Similar cognitive outcomes were observed across language groups. However, an interaction effect with stroke-onset group was observed, with monolinguals in the first-year group having worse productive language outcomes as compared to bilinguals. Interpretation: Overall, no detrimental effects of bilingualism were found on children's poststroke cognition and linguistic development. Our study suggests that a bilingual environment may facilitate language development in children poststroke.

Consensus-Based Evaluation of Outcome Measures in Pediatric Stroke Care: A Toolkit

Following a pediatric stroke, outcome measures selected for monitoring functional recovery and development vary widely. We sought to develop a toolkit of outcome measures that are currently available to clinicians, possess strong psychometric properties, and are feasible for use within clinical settings. A multidisciplinary group of clinicians and scientists from the International Pediatric Stroke Organization comprehensively reviewed the quality of measures in multiple domains described in pediatric stroke populations including global performance, motor and cognitive function, language, quality of life, and behavior and adaptive functioning. The quality of each measure was evaluated using guidelines focused on responsiveness and sensitivity, reliability, validity, feasibility, and predictive utility. A total of 48 outcome measures were included and were rated by experts based on the available evidence within the literature supporting the strengths of their psychometric properties and practical use. Only three measures were found to be validated for use in pediatric stroke: the Pediatric Stroke Outcome Measure, the Pediatric Stroke Recurrence and Recovery Questionnaire, and the Pediatric Stroke Quality of Life Measure. However, multiple additional measures were deemed to have good psychometric properties and acceptable utility for assessing pediatric stroke outcomes. Strengths and weaknesses of commonly used measures including feasibility are highlighted to guide evidence-based and practicable outcome measure selection. Improving the coherence of outcome assessment will facilitate comparison of studies and enhance research and clinical care in children with stroke. Further work is urgently needed to close the gap and validate measures across all clinically significant domains in the pediatric stroke population.

Advances in the Diagnosis and Treatment of Pediatric Arterial Ischemic Stroke

Though rare, stroke in infants and children is an important cause of mortality and chronic morbidity in the pediatric population. Neuroimaging advances and implementation of pediatric stroke care protocols have led to the ability to rapidly diagnose stroke and in many cases determine the stroke etiology. Though data on efficacy of hyperacute therapies, such as intravenous thrombolysis and mechanical thrombectomy, in pediatric stroke are limited, feasibility and safety data are mounting and support careful consideration of these treatments for childhood stroke. Recent therapeutic advances allow for targeted stroke prevention efforts in high-risk conditions, such as moyamoya, sickle cell disease, cardiac disease, and genetic disorders. Despite these exciting advances, important knowledge gaps persist, including optimal dosing and type of thrombolytic agents, inclusion criteria for mechanical thrombectomy, the role of immunomodulatory therapies for focal cerebral arteriopathy, optimal long-term antithrombotic strategies, the role of patent foramen ovale closure in pediatric stroke, and optimal rehabilitation strategies after stroke of the developing brain.

Outcome in Childhood Stroke: Comparing Functional Outcome by Modified Rankin Scale with Neurological Outcome by Pediatric Stroke Outcome Measure

Different scales are used as outcome predictors following arterial ischemic stroke (AIS) in children. Pediatric stroke outcome measure (PSOM) gives information about neurological deficits and function and modified Rankin scale (mRS) about functional outcome. Research examining the relationship between the two measures is scarce. The aim of this study is to correlate the two different scales and to get some information on the long course of outcomes according to these outcome measures. Sixty-one children with the diagnosis of AIS and normal neurodevelopment prior to stroke were investigated. Results of outcome measures (PSOM and mRS) from ≥ 2 years of follow-up were analyzed. Changes of neurological deficits (subcategories of PSOM) over time (discharge, 6 months, and ≥2 years) and prognostic impact on the outcome of the Pediatric National Institutes of Health Stroke Scale and etiology/risk factors are presented.

Cramer's V with a coefficient of 0.836 (df-1) indicates a strong association between dichotomized total PSOM and mRS scores. The correlation between the total scales was strong (rho = 0.983, p < 0.001). The correlation coefficient was highest for sensorimotor (rho = 0.949, p < 0.001), then for language (rho = 0.464, p < 0.001) and cognitive (rho = 0.363, p = 0.004) subscales. PSOM scores improved at 6 months compared to the discharge state in sensorimotor (p<0.001) and language (p<0.026) domains, however, there was no statistically significant difference between PSOM scores at 6 months and >2 years follow-up. There was no improvement in cognitive PSOM scores during the follow-up period.

There was a high concordance level between the two scales, illustrating that long-term neurological deficits after stroke are related to poor functional outcome. Significant improvement of sensorimotor and language function happened within the period from onset to 6 months of follow-up. Thus, early mobilization of appropriate rehabilitative therapy might improve the outcome. We conclude that both outcome classifications are applicable for assessing outcome after childhood AIS.

The influential factors and non-pharmacological interventions of cognitive impairment in children with ischemic stroke

Background

The prevalence of pediatric ischemic stroke rose by 35% between 1990 and 2013. Affected patients can experience the gradual onset of cognitive impairment in the form of impaired language, memory, intelligence, attention, and processing speed, which affect 20-50% of these patients. Only few evidence-based treatments are available due to significant heterogeneity in age, pathological characteristics, and the combined epilepsy status of the affected children.

Methods

We searched the literature published by Web of Science, Scopus, and PubMed, which researched non-pharmacological rehabilitation interventions for cognitive impairment following pediatric ischemic stroke. The search period is from the establishment of the database to January 2022.

Results

The incidence of such impairment is influenced by patient age, pathological characteristics, combined epilepsy status, and environmental factors. Non-pharmacological treatments for cognitive impairment that have been explored to date mainly include exercise training, psychological intervention, neuromodulation strategies, computer-assisted cognitive training, brain-computer interfaces (BCI), virtual reality, music therapy, and acupuncture. In childhood stroke, the only interventions that can be retrieved are psychological intervention and neuromodulation strategies.

Conclusion

However, evidence regarding the efficacy of these interventions is relatively weak. In future studies, the active application of a variety of interventions to improve pediatric cognitive function will be necessary, and neuroimaging and electrophysiological measurement techniques will be of great value in this context. Larger multi-center prospective longitudinal studies are also required to offer more accurate evidence-based guidance for the treatment of patients with pediatric stroke.

Rehabilitation for Pediatric Stroke in Low and Middle Income Countries: A Focused Review

Rehabilitation for pediatric stroke survivors can maximize a child's potential through each developmental stage of life. Timely diagnosis and referral to a rehabilitation specialist may harness opportunities to maximize brain plasticity, to help children adapt and learn, and to participate in and enjoy daily life to their capability. The aim of this focused review is to explore current rehabilitation models and evidence-based interventions for pediatric stroke survivors in Low- and Middle- Income Countries (LMICs) and to provide recommendations for future research and focused areas of improvement.There are several published pediatric stroke guidelines from the American Heart Association (AHA), Canada, Australia, and the United Kingdom (UK) which provide specific recommendations for rehabilitation, although the suggested intervention and services vary. There are no current guidelines developed in or contextually adapted for LMICs, although the current pediatric stroke guidelines emphasize the need to develop interventions that fit the cultural and environmental contexts. The World Health Organization (WHO) Rehabilitation 2030 initiative acknowledges profound unmet rehabilitation needs around the world, especially in LMICs. According to the WHO, LMICs have less than ten skilled rehabilitation professionals per one million people. Enhancing the understanding of rehabilitation services in LMICs could lead to nationally supported workforce education initiatives targeted to expand the number of locally trained therapy providers. This could improve access to and delivery of quality rehabilitation interventions to pediatric stroke survivors in these settings.

Neuromotor Rehabilitation Interventions After Pediatric Stroke: A Focused Review

Pediatric stroke is a condition that often results in life-long motor, cognitive, or sensory deficits for children. The purpose of this focused review is to compile the most recent literature on pediatric stroke neuromotor interventions and summarize evidence for use by rehabilitation providers and researchers. Terms including stroke, pediatric, and neuromotor were searched with appropriate MeSH terms. Information was collected regarding interventions conducted and outcome measures used for each article. Interventions and outcome measures were organized based on ICF components (Body Structure and Function, Activity, Participation, and Environmental Factors). 16 articles were included after full-text screens. From these 16 articles, a large majority of them included some form of neuromodulation as a part of intervention. Results identified a potentially problematic gap between domains addressed by interventions and measured by outcomes, with a need to include more expansive outcome measures in research studies. There are several areas of potential growth in pediatric stroke literature. Research studies should be precise when describing included samples. As interventions for pediatric stroke shift toward neuromodulation and other neurologic treatments, there is a need for well-defined populations, both clinically in the community as well as in research studies. There is also a need for US guidelines for rehabilitation after pediatric stroke. Overall, the trend in the literature seems to suggest that combining some form of neuromodulatory technique with existing recommended rehabilitation technique (ex: CIMT) may promote overall recovery for children after stroke, though further research is needed.

Thalamic Volume Loss Is Greater in Children Than in Adults Following Middle Cerebral Artery Territory Arterial Ischemic Stroke

Background: Younger stroke patients may suffer worse outcomes than older patients; however, the extent to which age at stroke impacts remote areas of the brain remains unclear. The objective of this study was to determine thalamic volume changes ipsilateral to middle cerebral artery territory strokes based on age at acute ischemic stroke onset. Methods: Acute ischemic stroke patients <9 years, 9-18 years, and >18 years old were retrospectively recruited from a large quaternary care system. Each subject underwent an acute (<72 hours from AIS) and chronic (>90 days) magnetic resonance imaging (MRI) scan. Manual thalamic segmentation was performed. Results: Younger and older children had significantly greater stroke-side thalamic volume loss compared to adults (48.2%, P = .022; 40.7%, P = .044, respectively). Conclusions: Stroke-side thalamic volumes decreased across the age spectrum but to a greater degree in pediatric patients. This observation can affect functional and cognitive outcomes post stroke and warrants further research.

Using causal methods to map symptoms to brain circuits in neurodevelopment disorders: moving from identifying correlates to developing treatments

A wide variety of model systems and experimental techniques can provide insight into the structure and function of the human brain in typical development and in neurodevelopmental disorders. Unfortunately, this work, whether based on manipulation of animal models or observational and correlational methods in humans, has a high attrition rate in translating scientific discovery into practicable treatments and therapies for neurodevelopmental disorders.With new computational and neuromodulatory approaches to interrogating brain networks, opportunities exist for "bedside-to bedside-translation" with a potentially shorter path to therapeutic options. Specifically, methods like lesion network mapping can identify brain networks involved in the generation of complex symptomatology, both from acute onset lesion-related symptoms and from focal developmental anomalies. Traditional neuroimaging can examine the generalizability of these findings to idiopathic populations, while non-invasive neuromodulation techniques such as transcranial magnetic stimulation provide the ability to do targeted activation or inhibition of these specific brain regions and networks. In parallel, real-time functional MRI neurofeedback also allow for endogenous neuromodulation of specific targets that may be out of reach for transcranial exogenous methods.Discovery of novel neuroanatomical circuits for transdiagnostic symptoms and neuroimaging-based endophenotypes may now be feasible for neurodevelopmental disorders using data from cohorts with focal brain anomalies. These novel circuits, after validation in large-scale highly characterized research cohorts and tested prospectively using noninvasive neuromodulation and neurofeedback techniques, may represent a new pathway for symptom-based targeted therapy.

Childhood stroke

Stroke is an important cause of neurological morbidity in children; most survivors have permanent neurological deficits that affect the remainder of their life. Stroke in childhood, the focus of this Primer, is distinguished from perinatal stroke, defined as stroke before 29 days of age, because of its unique pathogenesis reflecting the maternal-fetal unit. Although approximately 15% of strokes in adults are haemorrhagic, half of incident strokes in children are haemorrhagic and half are ischaemic. The causes of childhood stroke are distinct from those in adults. Urgent brain imaging is essential to confirm the stroke diagnosis and guide decisions about hyperacute therapies. Secondary stroke prevention strongly depends on the underlying aetiology. While the past decade has seen substantial advances in paediatric stroke research, the quality of evidence for interventions, such as the rapid reperfusion therapies that have revolutionized arterial ischaemic stroke care in adults, remains low. Substantial time delays in diagnosis and treatment continue to challenge best possible care. Effective primary stroke prevention strategies in children with sickle cell disease represent a major success, yet barriers to implementation persist. The multidisciplinary members of the International Pediatric Stroke Organization are coordinating global efforts to tackle these challenges and improve the outcomes in children with cerebrovascular disease.

A Computational Framework for Controlling the Self-Restorative Brain Based on the Free Energy and Degeneracy Principles

The brain is a non-linear dynamical system with a self-restoration process, which protects itself from external damage but is often a bottleneck for clinical treatment. To treat the brain to induce the desired functionality, formulation of a self-restoration process is necessary for optimal brain control. This study proposes a computational model for the brain's self-restoration process following the free-energy and degeneracy principles. Based on this model, a computational framework for brain control is established. We posited that the pre-treatment brain circuit has long been configured in response to the environmental (the other neural populations') demands on the circuit. Since the demands persist even after treatment, the treated circuit's response to the demand may gradually approximate the pre-treatment functionality. In this framework, an energy landscape of regional activities, estimated from resting-state endogenous activities by a pairwise maximum entropy model, is used to represent the pre-treatment functionality. The approximation of the pre-treatment functionality occurs via reconfiguration of interactions among neural populations within the treated circuit. To establish the current framework's construct validity, we conducted various simulations. The simulations suggested that brain control should include the self-restoration process, without which the treatment was not optimal. We also presented simulations for optimizing repetitive treatments and optimal timing of the treatment. These results suggest a plausibility of the current framework in controlling the non-linear dynamical brain with a self-restoration process.

Coronavirus Infections in the Nervous System of Children: A Scoping Review Making the Case for Long-Term Neurodevelopmental Surveillance

BACKGROUND

The objective of this study was to describe the case literature of human coronavirus infections in the nervous system of children, including from SARS-CoV-2, and to provide guidance to pediatric providers for managing the potential long-term effects on neurodevelopment of human coronavirus infections in the nervous system.

METHODS

Using a structured strategy, the PubMed and Ovid:Embase databases were queried for articles about the clinical presentation and pathophysiology of coronavirus infections in the nervous system of children and young adults, aged 0 to 24 years.

RESULTS

Of 2302 articles reviewed, 31 described SARS-CoV-2 infections in the nervous system of children and 21 described other human coronaviruses: HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1, MERS-CoV, SARS-CoV-1. Excepting MERS-CoV, we found cases of neurological disease in children from each human coronavirus. Children with non-SARS-CoV-2 infections have suffered acute flaccid paralysis, acute disseminated encephalomyelitis, encephalitis, and seizures. In addition, cases of ischemic, hemorrhagic, and microvascular strokes have occurred in children with SARS-CoV-2. Patients with multisystem inflammatory syndrome in children have suffered encephalitis, stroke, pseudotumor cerebri syndrome, and cytotoxic lesions of deep brain structures. Despite these reports, few articles evaluated the impact of human coronavirus infections on long-term neurodevelopmental domains including cognitive, language, academic, motor, and psychosocial outcomes.

CONCLUSIONS

Neurological manifestations of human coronavirus infections can cause severe disease in children. The case literature suggests a critical gap in knowledge of the long-term effects on child neurodevelopment of these infections. As the current SARS-CoV-2 pandemic continues, this gap must be filled to facilitate optimal outcomes in recovering children.

A computational framework for optimal control of a self-adjustive neural system with activity-dependent and homeostatic plasticity

The control of the brain system has received increasing attention in the domain of brain science. Most brain control studies have been conducted to explore the brain network's graph-theoretic properties or to produce the desired state based on neural state dynamics, regarding the brain as a passively responding system. However, the self-adjusting nature of neural system after treatment has not been fully considered in the brain control. In the present study, we propose a computational framework for optimal control of the brain with a self-adjustment process in the effective connectivity after treatment. The neural system is modeled to adjust its outgoing effective connectivity as activity-dependent plasticity after treatment, followed by synaptic rescaling of incoming effective connectivity. To control this neural system to induce the desired function, the system's self-adjustment parameter is first estimated, based on which the treatment is optimized. Utilizing this framework, we conducted simulations of optimal control over a functional hippocampal circuitry, estimated using dynamic causal modeling of voltage-sensitive dye imaging from the wild type and mutant mice, responding to consecutive electrical stimuli. Simulation results for optimal control of the abnormal circuit toward a healthy circuit using a single node treatment, neural-type specific treatment as an analogy of medication, and combined treatments of medication and nodal treatment suggest the plausibility of the current framework in controlling the self-adjusting neural system within a restricted treatment setting. We believe the proposed computational framework of the self-adjustment system would help optimal control of the dynamic brain after treatment.