Nonverbal Learning Disabilities Research Articles

Estimating the prevalence of Non-Verbal Learning Disability (NVLD) from the ABCD sample.

Non-Verbal Learning Disability (NVLD) is a neurodevelopmental disorder characterized by deficits in processing visuospatial information but with age-appropriate verbal skills. This cognitive profile has been hypothesized to be associated with atypical white matter, but at the present there is a lack of evidence for this hypothesis. Currently, the condition is not characterized within the main diagnostic systems, in part because no clear set of criteria for characterizing the disorder exists. This report is the first attempt to estimate NVLD prevalence, using two sets of diagnostic criteria, in a large sample of over 11,000 children who were selected without regards to problems of specific nature, either psychological, neurological, physical and/or social. Furthermore, it examined the association between the profile of cognitive abilities and aspects of whole-brain white matter measures in children with and without symptoms associated with NVLD. Participants were drawn from the Adolescent Brain Cognitive Development (ABCD) study, a 10-year longitudinal study of 11,876 children in the U.S. The data used in the present study were drawn from the initial testing point at which the children were 9-10years old. Prevalence of NVLD based on two distinct sets of criteria, correlations between the measures used to create the criteria, correlations between criteria measures and measures of white matter integrity. The cognitive criteria included measures of visuospatial processing, reading, intelligence and social skills. By varying the cut-offs applied to social skills in conjunction with visuo-spatial difficulties, spared reading skills and intelligence scores, we calculated prevalence for two NVLD groups. White matter characteristics were measures of volume, fractional anisotropy and mean diffusivity. Based on the criteria used, the estimated prevalence of NVLD varied from 1 to 8%. Furthermore, children with NVLD showed a dissociation between measures of visuo-spatial processing not observed in non-NVLD children. At the neurological level, findings provide preliminary evidenceof associations between the cognitive profile of NVLD and abnormalities in white matters tracts. The present study documents that exists, within this large non-selected sample, a proportion of youth who show evidence of NVLD. Given those results, it appears essential to establish the best diagnostic criteria, to improve the treatment options and quality of life for children with this disorder.

The Overlooked Role of Modalities in Multi-Exceptional Children

ABSTRACT Multi-exceptional children often have deficits in auditory, visual, or sensory processing. As few psychologists have training in modalities, these deficits may be misdiagnosed as AD/HD, Nonverbal Learning Disorder, Autism, Dyslexia, or a host of personality disorders. This article describes the symptoms of these processing deficits and offers suggestions for therapeutic interventions. Conundrums in diagnosing the complex profiles of multi-exceptional children are addressed. Qualitative assessment is recommended as an alternative or adjunct to traditional assessment. The Checklist for Recognizing Twice Exceptional Children is included to help parents, teachers, and graduate students gain awareness of the many manifestations of multi-exceptionality. The author’s experience as a clinician specializing in multi-exceptional children serves as the basis for the article.

45 Can Surgical Ablation Modify a Developmental Visuospatial Impairment in Periventricular Nodular Heterotopia? A Case Study

Objective:Periventricular nodular heterotopia (PVNH) is a malformation of cortical development (MCD) characterized by aggregates of gray matter adjacent to the lateral ventricular walls. Clinical presentation is heterogeneous with higher rates of seizures and reading impairments typically in the setting of average IQ (Felker et al. 2011). The majority of neuropsychological inquiry has focused on reading fluency, though a single case study showed a neurocognitive profile consistent with nonverbal learning deficits in a 7-year old boy with suspected autosomal dominant bilateral heterotopia (McCann et al., 2008). Given the periventricular focus and potential for unilateral presentations, non-linguistic neurocognitive sequelae may be expected in cases affecting the non-dominant hemisphere, yet this remains largely unexplored. Surgical ablation by laser interstitial thermal therapy (LITT) is increasingly used for epilepsy management in PVNH (Thompson et al., 2016, Whiting et al. 2020). However, there are no reported studies exploring cognitive outcomes following LITT of focal PVNH.Participants and Methods:A 46-year-old, right handed, Black female with 16 years of education presented for management of medically refractory epilepsy. Epilepsy monitoring captured intermittent slow waves in the right temporal lobe, interictal polyspikes in the right temporal lobe, and three epileptic events all emanating from the right temporal lobe. MRI showed extensive migrational anomalies involving the right hemisphere posteriorly consistent with PVNH with no associated mesial temporal sclerosis. Pre-surgical neuropsychological evaluation showed a significant split in IQ, with verbal IQ = 99 and performance IQ = 76. Testing indicated circumscribed deficits in visuoperceptual judgement, visuoconstruction, visuospatial reasoning, non-verbal recall, and several executive weaknesses in the context of otherwise average neurocognitive functioning. Fine motor speed was impaired bilaterally. Her profile was suggestive of non-dominant fronto-parieto-temporal dysfunction, concordant with the remainder of her work-up. By history she reported longstanding academic weaknesses in math and organization with strong verbal and reading abilities.Results:The patient underwent partial LITT of right PVNH sparing areas involved in visual function. At 6-month follow-up she was seizure free (Engel outcome 1A). Post-surgical neuropsychological evaluation showed reliable improvements in perceptual reasoning, aspects of learning/memory, and verbal naming. Visuoconstruction remained impaired but qualitatively improved. She also reported subjective experience of improved mental clarity and was applying for jobs after regaining driving privileges.Conclusions:This case demonstrates symptoms and history concerning for a nonverbal learning disorder in an adult woman with epilepsy secondary to right hemisphere PVNH and underscores the importance of exploring the range of neurocognitive profiles in MCD. Her notable neurocognitive and functional improvements following surgical ablation and seizure freedom suggest a possible release of function in the absence of inhibitory neurophysiological influences. This raises interesting questions about the endurance of her developmental profile. This case report contributes to our understanding of neuroanatomical correlates of neurocognitive and neurodevelopmental presentations. Future investigations should explore neuropsychological changes following LITT for PVNH.

B - 106 Case Illustration of an Adolescent with Nonverbal Learning Disability and Mosiac Turner Syndrome: Neuropsychological and Personality Assessment.

Nonverbal Learning Disability (NLD) is a controversial diagnosis which continues to lack an agreed upon diagnostic taxonomy despite its long existence and overlap with other disorders. NLD is considered a dysfunction of the right hemisphere with neuropsychological, academic, and social-emotional/adaptation deficits along with poor motor coordination. This case study reviews an adolescent diagnosed with NLD and Mosaic Turner Syndrome (MTS) and discusses challenges encountered to emphasize importance of an early diagnostic accuracy and the effect of developmental conditions. A 17-year-old female presented for neuropsychological evaluation for a mental health diagnosis and possible academic accommodations. Chief complaints included lifelong functionally interfering difficulties with attention, organization, and emotional and social functioning. Medical history was significant for MTS. The patient's VCI was in the high-average range (VCI = 114), while her PSI was in the low-average range (PSI = 81). She demonstrated high-average to average visual-spatial, construction abilities, and language skills, while performance ranged low-average for perceptual-motor processing and processing speed. Performance on delayed visual-graphic figures was significantly weaker compared to her superior performance on verbal memory for meaningful information. Finally, her delayed visual-graphic was significantly impaired compared to her general performance visual-spatial and construction abilities. The constellation of symptoms reported by the patient, combined with the results of neuropsychological assessment, was highly congruent with prototypical nonverbal learning disability, except for difficulties in mathematical skills. This case demonstrates the importance of proper diagnosis during childhood, the role of neuropsychological evaluation in specific learning disability (SLD) assessment, and lasting effects of a developmental condition on adult functioning.

Developmental Visual-Spatial Disorder (Nonverbal Learning Disability): What It Is and How to Recognize It and Provide Intervention in Clinical Practice

Developmental Visual-Spatial Disorder (Nonverbal Learning Disability): What It Is and How to Recognize It and Provide Intervention in Clinical Practice

Visual-Motor Integration Deficits in 3q29 Deletion Syndrome.

3q29 deletion syndrome (3q29del) is associated with neuropsychiatric and neurodevelopmental phenotypes. We previously reported that graphomotor weakness is present in up to 78% of individuals with 3q29del. We have now explored nuances of the graphomotor phenotype and its association with other comorbidities in this population. Participants were recruited from the online 3q29 registry (3q29deletion.org) for two days of deep phenotyping. 32 individuals with 3q29del (62.5% male) were evaluated with the Beery-Buktenica Developmental Test of Visual-Motor Integration (VMI) to assess visual-motor integration. Participants were also evaluated with measures of cognitive ability, executive function, adaptive behavior, and school function. Males with 3q29del performed significantly worse than females on the VMI and Motor Coordination subtest. VMI performance was significantly associated with ADHD diagnosis and cognitive ability. Compared to published data from individuals with 22q11.2 deletion syndrome, individuals with 3q29del showed significantly more impairment. The 3q29 deletion is associated with substantial deficits in visual-motor integration, Visual Perception, and Motor Coordination. Our data suggests that 3q29del may qualify as a nonverbal learning disability. Future studies should assess whether individuals with 3q29del would benefit from early interventions, including occupational therapy.

Trajectory assessments of cognitive, visuospatial, and academic profile in nonverbal learning disability (visuospatial developmental disorder)

Substantial progress has been made in defining children with nonverbal learning disability (NLD), but longitudinal studies are still lacking. To start filling this gap, we examined changes in general cognitive functioning, visuo-constructive skills, and academic profiles in a group of children with NLD, also taking into account any internalizing and externalizing symptom as transdiagnostic features.A total of 30 participants (24 boys) diagnosed with NLD were tested twice, with a three-year gap between the two assessments (T1: at age 8–13; T2: at 11–16), on their cognitive profile, visuospatial abilities, and academic performance (i.e., reading, writing and arithmetic abilities). At T2, any internalizing and externalizing symptom was also investigated.Statistically significant differences emerged between the two assessments in terms of the WISC-IV Perceptual Reasoning Index (PRI), handwriting speed and arithmetical fact retrieval.The NLD profile seems to be characterized by a relative stability in its core features during a child’s development, as regards both weaknesses (i.e., visuospatial processing) and strengths (i.e., verbal abilities). The presence of internalizing and externalizing symptoms also suggested the importance to analyze transdiagnostic features rather than only sharp boundaries between conditions.

Resting State Dynamic Reconfiguration of Spatial Attention Cortical Networks and Visuospatial Functioning in Non-Verbal Learning Disability (NVLD): A HD-EEG Investigation.

Nonverbal learning disability (NVLD) is a neurodevelopmental disorder characterized by deficits in visuospatial processing but spared verbal competencies. Neurocognitive markers may provide confirmatory evidence for characterizing NVLD as a separate neurodevelopmental disorder. Visuospatial performance and high-density electroencephalography (EEG) were measured in 16 NLVD and in 16 typically developing (TD) children. Cortical source modeling was applied to assess resting-state functional connectivity (rs-FC) in spatial attention networks (dorsal (DAN) and ventral attention networks (VAN)) implicated in visuospatial abilities. A machine-learning approach was applied to investigate whether group membership could be predicted from rs-FC maps and if these connectivity patterns were predictive of visuospatial performance. Graph theoretical measures were applied to nodes inside each network. EEG rs-FC maps in the gamma and beta band differentiated children with and without NVLD, with increased but more diffuse and less efficient functional connections bilaterally in the NVLD group. While rs-FC of the left DAN in the gamma range predicted visuospatial scores for TD children, in the NVLD group rs-FC of the right DAN in the delta range predicted impaired visuospatial performance, confirming that NVLD is a disorder with a predominant dysfunction in right hemisphere connectivity patterns.

A-3 Small-Vessel Childhood Primary Angiitis of the CNS: A Longitudinal Case Study

Abstract Childhood primary angiitis of the central nervous system (cPACNS) is a rare autoimmune and cerebrovascular inflammatory disease associated with cognitive, behavioral, psychiatric, motor, sensory and/or visual symptoms. This longitudinal case study describes deficits associated with a rare course of refractory small vessel cPACNS (sv-cPACNS) with presentation uncharacteristically confined to the right hemisphere. Improved understanding of sv-cPACNS may promote diagnostic clarity and subsequent intervention for a rare and often refractory presentation that is scientifically underserved. Records indicate onset of acute events (paralysis, migraines, stroke-like symptoms) with diagnosis of sv-cPACNS based on brain biopsy. MRI revealed abnormalities restricted to the right cerebral hemisphere. Treatments included high-dose steroids, chemotherapy, IVIg, and other immunomodulatory agents. Treatment course was refractory with many failed therapies until remission on current monoclonal antibody regimen (Natalizumab). Patient was referred due to poor academic and social progression. Neuropsychological results indicated a profile congruent with nonverbal learning disorder, including dysfunction in visuospatial reasoning, fine motor, mathematics, and social judgement. Compared to prior evaluation (age 11), reduced overall intellectual functioning, working memory, and processing speed were observed. This case study examines an 18-year-old patient with sv-cPACNS and cognitive difficulties. Results were consistent with limited research demonstrating low average intellectual functioning with longitudinal declines in working memory and processing speed. Results enhance the current understanding of sv-cPACNS by illustrating a nonverbal learning disorder profile, coinciding with right hemispheric involvement. Unfortunately, the long-term impact on cognitive functioning, especially in small-vessel disease subtype, is still not well understood. Findings add to phenotypic variability and developmental course of previously refractory sv-cPACNS.

Do comorbid symptoms discriminate between autism spectrum disorder, ADHD and nonverbal learning disability?

Characterizing the functioning of individuals with neurodevelopmental disorders is crucial to their diagnosis. Research has found that children with different neurodevelopmental disorders, including autism spectrum disorders (ASD), attention deficit and hyperactivity disorder (ADHD), and nonverbal learning disability (NLD), may have comorbid symptoms of anxiety and depression, and problems with pragmatic language. The main aim of the present study was to identify any differences in the above-mentioned comorbid symptoms associated with these clinical profiles. A second aim was to establish how well signs of pragmatic language difficulties could discriminate between the three clinical profiles, in terms of their diagnostic power. For this purpose, 107 participants from 8 to 16 years old with a diagnosis of ASD, ADHD or NLD were compared with a group of typically-developing children. Self-reports on symptoms of anxiety and depression, and parents’ reports on social and communication problems were analyzed. Our findings confirmed that symptoms of anxiety and depression, and problems with pragmatic language are associated with different neurodevelopmental disorders, but not in the same way. In terms of diagnostic power, we found that pragmatic language difficulties clearly discriminated children with ASD, ADHD or NLD from typically-developing children. Importantly, pragmatic language difficulties also discriminated adequately between ASD and NLD. Our findings are discussed in terms of the value of considering comorbid symptoms to obtain a more accurate diagnosis of neurodevelopmental disorders.

Children With Disabilities Express Less Concrete Gender-Based Biases:

Abnormalities with processing social concepts as children may display with Autism Spectrum Disorder (ASD) and Nonverbal learning disorder (NSLD). The purpose of the study was to observe how children with disabilities and nondisabled children viewed gender stereotypes. Images of gender-advertised toys and clothing items were utilized to determine gender-biases held by preschoolers (ages 3-6), upper-elementary level students (ages 10-12), and high school level students (ages 15-18). This project raises awareness of cultural stereotypes in society and their impact on childhood perception development. 177 students were shown images of gender-advertised clothing and entertainment items and asked to categorize each object as a boy, girl, or both. Students with disabilities had less gender bias compared to their nondisabled counterparts. The children in all groups had increased stereotyped responses to clothing items as opposed to toys. The preschoolers displayed the most stereotypical responses, the upper-elementary schoolers responded with the least biased responses as they had gained more exposure to toy and clothing options, and the highschoolers solidified their opinions with moderate stereotypes, notably in clothing items. Presenting increased non-stereotypical opinions, there was a significant difference in gender perception in students with disabilities. The difference in responses to gender perception between students with and without disabilities assimilated in all categories by high school age, meaning there was no significant difference in gender perception by this stage.

Contributions of Cerebellar White Matter Microstructure to Social Difficulty in Nonverbal Learning Disability.

Emerging evidence suggests that the cerebellum may contribute to variety of cognitive capacities, including social cognition. Nonverbal learning disability (NVLD) is characterized by visual-spatial and social impairment. Recent functional neuroimaging studies have shown that children with NVLD have altered cerebellar resting-state functional connectivity, which is associated with various symptom domains. However, little is known about cerebellar white matter microstructure in NVLD and whether it contributes to social deficits. Twenty-seven children (12 with NVLD, 15 typically developing (TD)) contributed useable diffusion tensor imaging data. Tract-based spatial statistics (TBSS) were used to quantify fractional anisotropy (FA) in the cerebellar peduncles. Parents completed the Child Behavior Checklist, providing a measure of social difficulty. Children with NVLD had greater fractional anisotropy in the left and right inferior cerebellar peduncle. Furthermore, right inferior cerebellar peduncle FA was associated with social impairment as measured by the Child Behavior Checklist Social Problems subscale. Finally, the association between NVLD diagnosis and greater social impairment was mediated by right inferior cerebellar peduncle FA. These findings provide additional evidence that the cerebellum contributes both to social cognition and to the pathophysiology of NVLD.

비언어성 학습장애(Non-Verbal Learning Disorder) 아동의 불안 감소를 위한 인지행동치료와 인지행동치료․시각주의훈련의 효과 비교

본 연구의 목적은 비언어성 학습장애 아동의 불안 감소를 위한 인지행동치료(CBT)와 인지행동치료․시각 주의훈련의 효과를 비교하는 것이다. 연구 대상은 서울 소재 초․중학교 만 7∼13세 아동 65명에게 K-WISC-III, K-ROCF, K-CBCL를 실시하여 선별하였고, CBT․시각주의훈련 집단, CBT 집단, 통제집단에 각 각 8명씩 배정하였다. CBT 프로그램과 CBT․시각주의훈련 프로그램은 주 2회, 총 10회기 동안 개별 진행 되었다. CBT 프로그램은 매 회기 60분씩 진행되었으며, CBT․시각주의훈련 프로그램은 CBT 프로그램 실 시 후 시각주의훈련을 20분 추가하여 진행되었다. 본 연구의 주요 결과는 다음과 같다. 첫째, 프로그램 사 전-사후 CBT 집단과 CBT․시각주의훈련 집단 모두 인지적 특성(긍정적 자동적 사고의 증가, 부정적 자동 적 사고의 감소), 정서적 특성(불안, 사회불안의 감소), 행동적 특성(사회기술의 증가)에서 유의한 변화가 나 타났다. 둘째, 집단 간 사후 검사 비교 시 CBT 집단과 CBT․시각주의훈련 집단은 통제집단에 비해, CBT․ 시각주의훈련 집단은 CBT 집단에 비해 인지적 특성, 정서적 특성, 행동적 특성에서 유의한 차이를 보였다. 셋째, 프로그램 종료 2개월 후 추후검사 결과 CBT 집단과 CBT․시각주의훈련 집단 모두 프로그램의 효과 가 유지되고 있는 것으로 나타났다.

Altered structure and functional connectivity of the hippocampus are associated with social and mathematical difficulties in nonverbal learning disability.

The hippocampus is known to play a critical role in a variety of complex abilities, including visual-spatial reasoning, social functioning, and math. Nonverbal learning disability (NVLD) is a neurodevelopmental disorder characterized by deficits in visual-spatial reasoning that are accompanied by impairment in social function or mathematics, as well as motor or executive function skills. Despite the overlap between behaviors supported by the hippocampus and impairments in NVLD, the structure and function of the hippocampus in NVLD has not been studied. To address this gap in the literature, we first compared hippocampal volume and resting-state functional connectivity in children with NVLD (n = 24) and typically developing (TD) children (n = 20). We then explored associations between hippocampal structure, connectivity, and performance on measures of spatial, social, and mathematical ability. Relative to TD children, those with NVLD showed significant reductions in left hippocampal volume and greater hippocampal-cerebellar connectivity. In children with NVLD, reduced hippocampal volume associated with worse mathematical problem solving. Although children with NVLD exhibited more social problems (social responsiveness scale [SRS]) and higher hippocampal-cerebellar connectivity relative to TD children, greater connectivity was associated with fewer social problems among children with NVLD but not TD children. Such an effect may suggest a compensatory mechanism. These structural and functional alterations of the hippocampus may disrupt its putative role in organizing conceptual frameworks through cognitive mapping, thus contributing to the cross-domain difficulties that characterize NVLD.

A comparison of local-global visuospatial processing in autism spectrum disorder, nonverbal learning disability, ADHD and typical development

BackgroundResearch on visuospatial functioning has revealed cognitive challenges for children with autism spectrum disorder (ASD), nonverbal learning disability (NLD) and attention deficit hyperactivity disorder (ADHD). These disorders are characterized by some overlapping symptoms, making their diagnosis a challenge. AimsThe study aims to clarify the role of visuospatial abilities in their neuropsychological profiles by investigating different visuospatial domains and their interplay with the local-global processing. Method and proceduresParticipants (N = 150) with ASD, NLD, or ADHD were compared with typically-developing (TD) children on visuospatial processing speed, visuo-perceptual abilities, visuo-constructive abilities, and visuospatial working memory. Generalized mixed-effects models were performed and receiver operating characteristic curves were estimated to express the usefulness of a local-global processing index in discriminating groups. Outcomes and resultsThe NLD group was impaired in all domains; children with ADHD revealed a heterogeneous profile, with greater impairments in visuospatial processing speed; ASD and TD groups were comparable. The local-global processing index had predictive power in discriminating among groups in visuo-constructive task. Conclusions and implicationsThe study of visuospatial abilities of children with ASD, NLD and ADHD might help to understand strengths and weaknesses in their neuropsychological profile and to differentiate between them. Clinical implications of these findings are discussed.

The Effect of Perceptual-Motor Training on Executive Functions in Children with Non-Verbal Learning Disorder.

PurposeResearch shows an atypical cognitive process in children with nonverbal learning disorder (NLD) compared to typically developing children, but a wealth of information indicates that physical activity can influence cognitive processes. However, little is known about the effects of perceptual-motor training and its impact on the cognitive process of children with NLD. Thus, the major goals of this study are to compare the executive functions (EFs) in children with NLD with typically developing children and then to investigate the effect of perceptual-motor training on EFs of children with NLD.MethodsTo achieve the first goal, 400 typically developing (IQ >80) and NLD children (7–13 years old) were randomly selected in the city of Mashhad, Iran, during the period 2017–2018. As for the second goal, 50 children with NLD were randomly assigned to an experimental or control group. To evaluate executive functions, Delis–Kaplan executive function system test was used at the pretest, posttest, and 3-month follow-up. The experimental group received the Werner and Reini’s perceptual-motor training program in sixteen 45-min sessions (three sessions per week), but the control group did not receive any intervention.ResultsThe results showed that children with NLD were significantly weaker than typically developing children in London Tower Test (t (38) = −4.662, p <0.01), Trail Making Test (t (33.926) = −3.11, p <0.01), Card Sorting Test (t (38) = −3.427, p <0.01), and Stroop Color Test (t (30.035) = −5.876, p <0.01). The Pilates training had an obvious effect on enhancing the performance of participants in the experimental group (p<0.001), but similar results were not observed in the control group.ConclusionChildren with NLD have problems in EFs, but perceptual-motor training can be used as an effective intervention for these children.

Nonverbal Learning Disability Is More Common Than Previously Thought

Nonverbal learning disability (NVLD) is characterized by deficits in visual-spatial, math, and social skills due to difficulties reading nonverbal

Estimated Prevalence of Nonverbal Learning Disability Among North American Children and Adolescents

Nonverbal learning disability (NVLD) is a neurodevelopmental disorder characterized by deficits in visual-spatial processing but not in reading or verbal ability; in addition, problems in math calculation, visual executive functioning, fine-motor skills, and social skills are often present. To our knowledge, there are no population-based estimates of the prevalence of NVLD in community samples. To estimate the prevalence of the NVLD cognitive profile in 3 independent samples of children and adolescents from studies centered around brain imaging in the US and Canada. This cross-sectional study used data from 2 samples recruited from the community and overselected for children with psychiatric disorders (Healthy Brain Network [HBN], January 1, 2015, to December 31, 2019, and Nathan Kline Institute-Rockland Sample [NKI], January 1, 2011, to December 31, 2018) and 1 community-ascertained population sample (Saguenay Youth Study [SYS], January 1, 2003, to December 31, 2012) overselected for active maternal smoking during pregnancy. Prevalence of NVLD. Criteria for NVLD were based on clinical records of deficits in visual-spatial reasoning and impairment in 2 of 4 domains of function (fine-motor skills, math calculation, visual executive functioning, and social skills). Sample weighting procedures adjusted for demographic differences in sample frequencies compared with underlying target populations. Inflation factor weights accounted for overrepresentation of psychiatric disorders (HBN and NKI samples). Across 3 independent samples, the prevalence of NVLD was estimated among 2596 children and adolescents aged 6 to 19 years (mean [SD] age, 12.5 [3.4] years; 1449 male [55.8%]). After sample and inflation weights were applied, the prevalence of NVLD was 2.78% (95% CI, 2.03%-3.52%) in the HBN sample and 3.9% (95% CI, 1.96%-5.78%) in the NKI sample. In the SYS sample, the prevalence of NVLD was 3.10% (95% CI, 1.93%-4.27%) after applying the sample weight. Across samples and estimation strategies, the population prevalence of NVLD was estimated to range from 3% to 4%. When applied to the US population younger than 18 years, 2.2 million to 2.9 million children and adolescents were estimated to have NVLD. The findings suggest that the prevalence of NVLD in children and adolescents may be 3% to 4%. Given that few youths are diagnosed with NVLD and receive treatment, increased awareness, identification of the underlying neurobiological mechanisms, and development and testing interventions for the disorder are needed.

The Importance of Defining Shared Criteria for the Diagnosis of Nonverbal Learning Disability

The Importance of Defining Shared Criteria for the Diagnosis of Nonverbal Learning Disability

Spatial Network Connectivity and Spatial Reasoning Ability in Children with Nonverbal Learning Disability

Nonverbal Learning Disability (NVLD) is characterized by deficits in visual-spatial, but not verbal, reasoning. Nevertheless, the functioning of the neural circuits supporting spatial processing have yet to be assessed in children with NVLD. We compared the resting state functional connectivity of a spatial brain network among children with NVLD, children with reading disorder (RD), and typically developing (TD) children. Seventy-five participants (7–15 years old) were included in the study (20 TD, 24 NVLD, and 31 RD). Group differences in global efficiency and functional connectivity among 12 regions comprising a previously defined spatial network were evaluated. Associations with behavior were explored. Global efficiency of the spatial network associated positively with spatial ability and inversely with socioemotional problems. Within the spatial network, associations between left posterior cingulate (PCC) and right retrosplenial cortical activity were reduced in children with NVLD relative to those without spatial deficits (RD and TD). Connectivity between left PCC and right posterior cerebellum (Crus I and II) was reduced in both groups of children with learning disabilities (NVLD and RD) relative to TD children. Functional connectivity of the spatial network was atypically associated with cognitive and socioemotional performance in children with NVLD. Identifying a neurobiological substrate for NVLD provides evidence that it is a discrete clinical entity and suggests targets for treatment.