Challenges and Neuropsychological Functioning in Children and Adolescents with Borderline Intellectual Functioning

Exploring the Clinical Characteristics and Comorbid Disorders of Borderline Intellectual Functioning

Borderline intellectual functioning (BIF) is characterized by cognitive impairment and deficits in adaptive functioning. Despite affecting a significant proportion of the population, BIF still remains underdiagnosed and poorly understood. In addition to cognitive impairments across a range of domains, individuals with BIF face a greater risk of academic failure and often require special educational support. They suffer from emotional problems, such as difficulties with emotional awareness, anxiety, depressed mood, and unhappiness. Individuals with BIF are more likely to have an impairment of social and adaptive functioning. Furthermore, individuals with BIF are at higher risk of physical and mental health problems, often receive inadequate treatment, and have a poorer prognosis. This review aims to enhance the understanding of clinicians, educators, and policymakers by providing an overview of the characteristics of BIF and its associated challenges, ultimately contributing to the improvement of support systems for individuals with BIF.

Epidemiology and Diagnosis of Slow Learners (Borderline Intellectual Functioning)

The definitions of "slow learners" and "borderline intellectual functioning (BIF)" have not reached a consensus and have continually evolved in terminology. The criteria for diagnosing BIF include the Full-Scale Intelligence Quotient, adaptive functioning, and onset of symptoms from the developmental period; however, specific standards have not been provided. Until the Diagnostic and Statistical Manual of Mental Disorders-IV, a range for the Full-Scale Intelligence Quotient was provided, but due to its limitations in reflecting the actual functioning of individuals with BIF, this criterion was removed from the Diagnostic and Statistical Manual of Mental Disorders-5. The absence of specific diagnostic criteria complicates the identification of individuals with BIF, highlighting the need for a more precise classification and definition.

Comprehensive analyses of neurodevelopmental outcomes and quality of life of children with biliary atresia

OBJECTIVES

To holistically evaluate neurodevelopmental outcomes and quality of life (QOL) of Japanese patients with biliary atresia (BA) and to investigate the factors associated with the outcomes.

METHODS

This study enrolled patients with BA aged 5-18 years who visited Osaka University Hospital in 2021. Neurodevelopmental assessments were performed to evaluate intellectual ability, cognitive functions and adaptive skill levels. Furthermore, emotional and behavioral issues, characteristics of attention deficit hyperactivity disorder, and QOL were concomitantly assessed in the same cohort. Biochemical and social factors associated with the results were examined.

RESULTS

Fifty-three patients, with a median age of 11.2 years were included in the analyses. Patients with BA had a significantly lower Full-Scale Intelligence Quotient or developmental quotient (FSIQ/DQ) score and Vineland Adaptive Behavior Scale (VABS) composite score than the general Japanese population. Household education level and short stature were associated with low and borderline FSIQ/DQ and VABS composite scores, respectively. Among patients with low and borderline FSIQ/DQ scores, those with average or high VABS composite scores received significantly less neuroeducational care than those with low and borderline VABS composite scores. Despite the low FSIQ/DQ and VABS composite scores, the total QOL scores were higher than those of the general population.

CONCLUSION

Patients with BA had intellectual and behavioral impairments. Notably, patients with intellectual impairments are overlooked and not followed up, especially if adaptive skills are maintained.

Hippocampal ΔFosB expression is associated with cognitive impairment in a subgroup of patients with childhood epilepsies

Epilepsy is a chronic neurological disorder characterized by recurrent seizures, and is often comorbid with other neurological and neurodegenerative diseases, such as Alzheimer's disease (AD). Patients with recurrent seizures often present with cognitive impairment. However, it is unclear how seizures, even when infrequent, produce long-lasting deficits in cognition. One mechanism may be seizure-induced expression of ΔFosB, a long-lived transcription factor that persistently regulates expression of plasticity-related genes and drives cognitive dysfunction. We previously found that, compared with cognitively-intact subjects, the activity-dependent expression of ΔFosB in the hippocampal dentate gyrus (DG) was increased in individuals with mild cognitive impairment (MCI) and in individuals with AD. In MCI patients, higher ΔFosB expression corresponded to lower Mini-Mental State Examination scores. Surgically resected DG tissue from patients with temporal lobe epilepsy also showed robust ΔFosB expression; however, it is unclear whether ΔFosB expression also corresponds to cognitive dysfunction in non-AD-related epilepsy. To test whether DG ΔFosB expression is indicative of cognitive impairment in epilepsies with different etiologies, we assessed ΔFosB expression in surgically-resected hippocampal tissue from 33 patients with childhood epilepsies who had undergone Wechsler Intelligence Scale for Children (WISC) testing prior to surgery. We found that ΔFosB expression is inversely correlated with Full-Scale Intelligence Quotient (FSIQ) in patients with mild to severe intellectual disability (FSIQ < 85). Our data indicate that ΔFosB expression corresponds to cognitive impairment in epilepsies with different etiologies, supporting the hypothesis that ΔFosB may epigenetically regulate gene expression and impair cognition across a wide range of epilepsy syndromes.