Altered resting-state neural networks in children and adolescents with functional neurological disorder

Altered brain dynamic functional connectivity in patients with obstructive sleep apnea and its association with cognitive performance

OBJECTIVES

Obstructive sleep apnea (OSA) is associated with potential disruptions in brain function and structure. The aim was to investigate alterations in dynamic functional connectivity (dFC) in OSA patients utilizing resting-state functional magnetic resonance imaging (rs-fMRI) and multiplication of temporal derivatives (MTD) to better understand the neurological implications of OSA.

METHODS

This cross-sectional study eventually recruited 111 patients, aged 25-65 years. We categorized participants based on the apnea-hypopnea index (AHI) assessed via polysomnography (PSG), 43 patients were groupAHI <15 and 68 patients were group AHI ≥15. Rs-fMRI and neuropsychological assessments were conducted to assess the brain function and visual-spatial memory, respectively. We evaluated the intergroup differences in dFC as well as its correlation with clinical parameters.

RESULTS

The dFC analysis identified five distinct connectivity states, comprising four hyperconnected states (State 1, 2, 3, and 5) and one hypoconnected state (State 4). Group AHI≥ 15 showed altered fraction time (FT) and mean dwell time (MDT) in States 1, 3, and 4. The partial correlation showed that the FT/MDT of State 1 negatively correlated with hypoxia parameters, while the FT/MDT of State 3 positively correlated with total sleep time in Group AHI≥ 15. Group AHI≥ 15 exhibited a negative association between FT of state 3 and Visuospatial/Executive score in MoCA (r = -0.297, p = 0.033).

CONCLUSIONS

Untreated male moderate to severe OSA patients exhibited altered in dFC, which significantly correlated with hypoxia parameters and cognitive performance, high lighting that dFC changes may be an indicator of the neurological consequence of OSA, especially moderate to severe OSA.

Large-scale functional network connectivity alterations in adolescents with major depression and non-suicidal self-injury

Non-suicidal self-injury (NSSI) is prevalent among adolescent populations worldwide, yet its neuropathological mechanisms remain unclear. This study aimed to investigate brain functional differences in NSSI patients by utilizing large-scale functional networks and examining their correlation with clinical outcomes. Cross-sectional clinical and functional magnetic resonance imaging (fMRI) data were collected from 42 patients and 47 healthy controls. Independent component analysis (ICA) was utilized to investigate changes in both intra-network and inter-network functional connectivity. We then investigated the potential association between functional network connectivity and clinical self-injurious behavior. The results revealed significant abnormalities in intra-network functional connectivity within the left middle cingulum gyrus, right angular gyrus, and middle frontal gyrus in patients with NSSI. Additionally, we found altered inter-network connectivity patterns, particularly between higher-order cognitive networks and primary sensory networks, suggesting potential disruptions in multisensory integration and emotional regulation in these patients. This study revealed significant alterations in large-scale functional network connectivity in adolescents with depression and NSSI, particularly in networks related to emotion regulation and cognitive control. These findings provide novel perspectives on the neurobiological mechanisms of NSSI and suggest possible avenues for early intervention and treatment.

Microstructure Abnormalities of Diffusion Tensor Imaging Measures in First-Episode, Treatment-Naïve Adolescents With Major Depressive Disorder: An Integrated AFQ and TBSS Study

PURPOSE

Structural changes during depressive episodes in adolescents with major depressive disorder (MDD) remains unclear due to participant heterogeneity, illness chronicity, and medication confounders. This study aimed to explore white matter (WM) microstructural changes in first-episode, treatment-naïve adolescents with MDD using an integrated diffusion tensor imaging (DTI) approach.

METHOD

We recruited 66 subjects, including 37 adolescents with MDD and 29 healthy controls. Two main DTI techniques, automated fiber quantification (AFQ) and tract-based spatial statistics (TBSS), were used to analyze fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD) in WM tracts. DTI measures were then correlated with the depressive symptoms evaluated by Hamilton Depression Rating Scale scores (HAMD-17).

FINDINGS

In AFQ, MDD patients showed significant segmental differences in WM tracts compared to controls, including a negative correlation between SLF AD values and depression severity. TBSS revealed reduced FA in the cingulum, forceps minor, inferior fronto-occipital fasciculus, inferior longitudinal fasciculus, SLF, and uncinate fasciculus in MDD.

CONCLUSION

Our integrated DTI analysis in a unique first-episode, medication-naïve cohort revealed microstructural changes in adolescent MDD not previously reported. These findings may provide imaging markers for early detection and enhance our understanding of depression pathology in youth.

Agreement and disagreement in pediatric functional neurological symptom disorders: Comparing patient reported outcome measures (PROMs) and clinician assessments

Youth with functional neurological symptom disorder (FNSD) often perceive themselves as having limited capabilities, which may not align with clinical evaluations. This study assessed the disparities between clinician evaluations and patient-reported outcome measures (PROMs) regarding pain, motor function, and learning difficulties in youth with FNSD. Sixty-two youths with FNSD participated in this study, all of whom reported experiencing pain, motor problems, and/or learning difficulties. Clinicians also assessed these domains, resulting in a two-by-two categorization matrix: (1) agreement: child and clinician report "problems"; (2) agreement: child and clinician report "no problems"; (3) disagreement: child reports "problems" while the clinician does not; and (4) disagreement: clinician reports "problems" while the child does not. Agreement/disagreement differences were analyzed. No significant differences in prevalence were observed between the evaluators regarding pain (clinician-85%, child-88%), motor (clinician-98%, child-95%), or learning problems (clinician-69%, child-61%). More than 80% of the children and clinicians report pain and motor disorders. Instances in which children and clinicians reported learning problems (40.3%) exceeded cases in which both reported no problems (9.6%) or only the child reported problems (20.9%). Overall, the agreement between pain and motor function assessments was high (>90%), whereas that concerning learning difficulties was moderate (49.9%). Disagreement in pain/motor assessments was minimal (<5%), whereas for learning difficulties, disagreement rates were high (>20%). In conclusion, a significant concordance exists between PROMs and clinician assessments of pain and motor problems. However, the higher frequency of disagreements regarding learning difficulties emphasizes the importance of incorporating patient and clinician evaluations in pediatric FNSD treatment.

Altered functional connectivity within the primary visual networks and neurotransmitter activity in male smokers: A group ICA study

Smoking puts patients at high risk for cognitive and psychiatric disorders. The aim of this study was to explore the effects of nicotine use on primary visual network (PVN) and its association with neurotransmitters. A total of 59 tobacco use disorder (TUD) patients and 51 healthy controls (HC) participated in this study and underwent resting state functional magnetic resonance imaging scans. Functional connectivity (FC) within the network was explored using independent component analysis. In addition, the spatial correlations of PVN changes with neurotransmitters and their correlations with clinical characteristics of patients were evaluated using the JuSpace toolbox and SPSS. We found reduced FC within the PVN in patients with TUD compared with HC. In terms of relevant analysis, there is a spatial correlation between FC changes in the patient's PVN and a higher distribution of dopamine receptor and gamma-aminobutyric acid receptor. This study revealed changes in the FC and neurotransmitters of the PVN in patients with TUD, expanding the potential neural mechanisms underlying sensory perception and psychiatric disorders.

Biomarkers and Rehabilitation for Functional Neurological Disorder

Functional neurological disorder, or FND, is widely misunderstood, particularly when considering recent research indicating that the illness has numerous biological markers in addition to its psychiatric disorder associations. Nonetheless, the long-held view that FND is a mental illness without a biological basis, or even a contrived (malingered) illness, remains pervasive both in current medical care and general society. This is because FND involves intermittent disability that rapidly and involuntarily alternates with improved neurological control. This has in turn caused shaming, perceived low self-efficacy, and social isolation for the patients. Until now, biomarker reviews for FND tended not to examine the features that are shared with canonical neurological disorders. This review, in contrast, examines current research on FND biomarkers, and in particular their overlap with canonical neurological disorders, along with the encouraging outcomes for numerous physical rehabilitation trials for FND. These findings support the perspective endorsed here that FND is unquestionably a neurological disorder that is also associated with many biological markers that lie outside of the central nervous system. These results suggest that FND entails multiple biological abnormalities that are widely distributed in the body. General healthcare providers would benefit their care for their patients through their improved understanding of the illness and recourses for support and treatment that are provided in this review.

Recent advances in understanding the neurobiology of pediatric functional neurological disorder

INTRODUCTION

Functional neurological disorder (FND) is a neuropsychiatric disorder that manifests in a broad array of functional motor, sensory, or cognitive symptoms, which arise from complex interactions between brain, mind, body, and context. Children with FND make up 10%-20% of presentations to neurology services in children's hospitals and up to 20% of adolescents admitted to hospital for the management of intractable seizures.

AREAS COVERED

The current review focuses on the neurobiology of pediatric FND. The authors present an overview of the small but growing body of research pertaining to the biological, emotion-processing, cognitive, mental health, physical health, and social system levels.

EXPERT OPINION

Emerging research suggests that pediatric FND is underpinned by aberrant changes within and between neuron-glial (brain) networks, with a variety of factors - on multiple system levels - contributing to brain network changes. In pediatric practice, adverse childhood experiences (ACEs) are commonly reported, and activation or dysregulation of stress-system components is a frequent finding. Our growing understanding of the neurobiology of pediatric FND has yielded important flow-on effects for assessing and diagnosing FND, for developing targeted treatment interventions, and for improving the treatment outcomes of children and adolescents with FND.

Multivariate patterns of brain functional connectome associated with COVID-19-related negative affect symptoms

Severe mental health problems with the representation of negative affect symptoms (NAS) have been increasingly reported during the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to explore the multivariate patterns of brain functional connectome predicting COVID-19-related NAS. This cohort study encompassed a group of university students to undergo neuroimaging scans before the pandemic, and we re-contacted participants for 1-year follow-up COVID-related NAS evaluations during the pandemic. Regularized canonical correlation analysis was used to identify connectome-based dimensions of NAS to compute pairs of canonical variates. The predictive ability of identified functional connectome to NAS dimensional scores was examined with a nested cross-validation. Two dimensions (i.e. mode stress and mode anxiety) were related to distinct patterns of brain functional connectome (r2 = 0.911, PFDR = 0.048; r2 = 0.901, PFDR = 0.037, respectively). Mode anxiety was characterized by high loadings in connectivity between affective network (AFN) and visual network (VN), while connectivity of the default mode network with dorsal attention network (DAN) were remarkably prominent in mode stress. Connectivity patterns within the DAN and between DAN and VN, ventral attention network, and AFN was common for both dimensions. The identified functional connectome can reliably predict mode stress (r = 0.37, MAE = 5.1, p < 0.001) and mode anxiety (r = 0.28, MAE = 5.4, p = 0.005) in the cross-validation. Our findings provide new insight into multivariate dimensions of COVID-related NAS, which may have implications for developing network-based biomarkers in psychological interventions for vulnerable individuals in the pandemic.

Neurometabolic alterations in children and adolescents with functional neurological disorder

OBJECTIVES

In vivo magnetic resonance spectroscopy (MRS) was used to investigate neurometabolic homeostasis in children with functional neurological disorder (FND) in three regions of interest: supplementary motor area (SMA), anterior default mode network (aDMN), and posterior default mode network (dDMN). Metabolites assessed included N-acetyl aspartate (NAA), a marker of neuron function; myo-inositol (mI), a glial-cell marker; choline (Cho), a membrane marker; glutamate plus glutamine (Glx), a marker of excitatory neurotransmission; γ-aminobutyric acid (GABA), a marker of inhibitor neurotransmission; and creatine (Cr), an energy marker. The relationship between excitatory (glutamate and glutamine) and inhibitory (GABA) neurotransmitter (E/I) balance was also examined.

METHODS

MRS data were acquired for 32 children with mixed FND (25 girls, 7 boys, aged 10.00 to 16.08 years) and 41 healthy controls of similar age using both short echo point-resolved spectroscopy (PRESS) and Mescher-Garwood point-resolved spectroscopy (MEGAPRESS) sequences in the three regions of interest.

RESULTS

In the SMA, children with FND had lower NAA/Cr, mI/Cr (trend level), and GABA/Cr ratios. In the aDMN, no group differences in metabolite ratios were found. In the pDMN, children with FND had lower NAA/Cr and mI/Cr (trend level) ratios. While no group differences in E/I balance were found (FND vs. controls), E/I balance in the aDMN was lower in children with functional seizures-a subgroup within the FND group. Pearson correlations found that increased arousal (indexed by higher heart rate) was associated with lower mI/Cr in the SMA and pDMN.

CONCLUSIONS

Our findings of multiple differences in neurometabolites in children with FND suggest dysfunction on multiple levels of the biological system: the neuron (lower NAA), the glial cell (lower mI), and inhibitory neurotransmission (lower GABA), as well as dysfunction in energy regulation in the subgroup with functional seizures.

Illness-Promoting Psychological Processes in Children and Adolescents with Functional Neurological Disorder

Previous studies suggest that subjective distress in children with functional neurological disorder (FND) is associated with stress-system dysregulation and modulates aberrant changes in neural networks. The current study documents illness-promoting psychological processes in 76 children with FND (60 girls and 16 boys, aged 10.00-17.08 years) admitted to the Mind-Body Program. The children completed a comprehensive family assessment and self-report measures, and they worked with the clinical team to identify psychological processes during their inpatient admission. A total of 47 healthy controls (35 girls and 12 boys, aged 8.58-17.92 years) also completed self-report measures, but were not assessed for illness-promoting psychological processes. Children with FND (vs. controls) reported higher levels of subjective distress (total DASS score, t(104.24) = 12.18; p ˂ 0.001) and more adverse childhood experiences across their lifespans (total ELSQ score, t(88.57) = 9.38; p ˂ 0.001). Illness-promoting psychological processes were identified in all children with FND. Most common were the following: chronic worries about schoolwork, friendships, or parental wellbeing (n = 64; 84.2%); attention to symptoms (n = 61; 80.3%); feeling sad (n = 58; 76.3%); experiencing a low sense of control (helplessness) in relation to symptoms (n = 44; 57.9%); pushing difficult thoughts out of mind (n = 44; 57.9%); self-critical rumination (n = 42; 55.3%); negative/catastrophic-symptom expectations (n = 40; 52.6%); avoidance of activities (n = 38; 50%); intrusive thoughts/feelings/memories associated with adverse events (n = 38, 50%); and pushing difficult feelings out of mind (n = 37; 48.7%). In children with FND-disabled enough to be admitted for inpatient treatment-illness-promoting psychological processes are part of the clinical presentation. They contribute to the child's ongoing sense of subjective distress, and if not addressed can maintain the illness process. A range of clinical interventions used to address illness-promoting psychological processes are discussed, along with illustrative vignettes.

Aberrant functional connectivity within and between brain networks in patients with early-onset bipolar disorder

OBJECTIVE

This study used independent component analysis (ICA) to investigate the connectivity patterns of resting-state functional large-scale brain networks in patients with early-onset bipolar disorder (BD).

METHODS

ICA was used to extract brain functional network components from 43 early-onset BD patients and 21 healthy controls (HCs). Then, the functional connectivity (FC) and functional network connectivity (FNC) within and between the independent brain networks was calculated, and the correlation between the connectivity changes and neuropsychological scale was evaluated.

RESULTS

Compared with HCs, FC increased in the right hippocampus and inferior temporal gyrus, and left triangular inferior frontal gyrus of the anterior default mode network (aDMN); right median cingulate and paracingulate gyri, and inferior parietal lobule of the posterior DMN (pDMN); and right precentral and postcentral gyrus of the sensorimotor network (SMN) in early-onset BD patients. However, FC decreased in the left superior frontal gyrus of the aDMN, left paracentral lobule of the SMN, and left lingual gyrus and calcarine of the visual network in early-onset BD patients. There was no significant correlation between FC values of differential brain regions within resting-state networks (RSNs) and neuropsychological scores (uncorrected p > 0.05). In addition, the FNC among the pDMN-auditory network, pDMN-visual network, left frontoparietal network (lFPN)-visual network, lFPN-aDMN and dorsal attention network-ventral attention network (DAN-VAN) were increased in early-onset BD patients. The zFNC of the pDMN-visual network was positively correlated with the anxiety/somatization score (r = 0.5833, p < 0.0001) and sleep disorders (r = 0.6150, p < 0.0001). The zFNC of the lFPN-aDMN was positively correlated with despair (r = 0.4505, p = 0.004 × 10 < 0.05 after Bonferroni correction). The zFNC of the DAN-VAN was positively correlated with cognitive impairment (r = 0.4598, p = 0.0032 × 10 < 0.05 after Bonferroni correction). The zFNC of the DAN-VAN showed a positive correlation trend with the Hamilton Depression Scale (HAMD) total score (r = 0.4404, p = 0.005 × 10 = 0.05 after Bonferroni correction).

CONCLUSIONS

Patients with early-onset BD showed changes in a wide range of neural functional networks, involving changes in executive control, attention, perceptual regulation, cognition and other neural networks, which may provide new imaging evidence for understanding the pathogenesis of early-onset BD and for therapeutic intervention targets.

Evidence-Based Mind-Body Interventions for Children and Adolescents with Functional Neurological Disorder

LEARNING OBJECTIVES

• Develop and implement treatment plans for children and adolescents with functional neurological disorder (FND)• Outline a plan to increase awareness and standardize the care for patients with FND using evidence-based interventions.

ABSTRACT

Functional neurological disorder (FND) in children and adolescents involves the biological embedding of lived experience in the body and brain. This embedding culminates in stress-system activation or dysregulation and in aberrant changes in neural network function. In pediatric neurology clinics, FND represents up to one-fifth of patients. Current research shows good outcomes with prompt diagnosis and treatment using a biopsychosocial, stepped-care approach. At present, however-and worldwide-FND services are scarce, the result of long-standing stigma and ingrained belief that patients with FND do not suffer from a real ("organic") disorder and that they therefore do not require, or even deserve, treatment. Since 1994, the Mind-Body Program for children and adolescents with FND at The Children's Hospital at Westmead in Sydney, Australia-run by a consultation-liaison team-has delivered inpatient care to hundreds of patients with FND and outpatient care to hundreds of others. For less-disabled patients, the program enables community-based clinicians to implement biopsychosocial interventions locally by providing a positive diagnosis (by a neurologist or pediatrician), a biopsychosocial assessment and formulation (by clinicians from the consultation-liaison team), a physical therapy assessment, and clinical support (from the consultation-liaison team and the physiotherapist). In this Perspective we describe the elements of a biopsychosocial mind-body program intervention capable of providing, as needed, effective treatment to children and adolescents with FND. Our aim is to communicate to clinicians and institutions around the world what is needed to establish effective community treatment programs, as well as hospital inpatient and outpatient interventions, in their own health care settings.

COVID-19 Vaccination in Young People with Functional Neurological Disorder: A Case-Control Study

BACKGROUND

The emergence of acute-onset functional neurological symptoms, the focus of this study, is one of three stress responses related to immunisation. This case-control study documents the experience of 61 young people with past or current functional neurological disorder (FND) in relation to the COVID-19 vaccination program in Australia.

METHODS

Information about the young person's/parent's choice and response pertaining to COVID-19 vaccination was collected as part of routine clinical care or FND research program follow-up.

RESULTS

61 young people treated for FND (47 females, mean age = 16.22 years) and 46 healthy controls (34 females, mean age = 16.37 years) were included in the study. Vaccination rates were high: 58/61 (95.1%) in the FND group and 45/46 (97.8%) in the control group. In the FND group, 2 young people (2/61, 3.3%) presented with new-onset FND following COVID-19 vaccination; two young people with resolved FND reported an FND relapse (2/36, 5.56%); and two young people with unresolved FND (2/20, 10.0%) reported an FND exacerbation. In the control group no FND symptoms were reported.

CONCLUSIONS

Acute-onset FND symptoms following COVID-19 vaccination are uncommon in the general population. In young people prone to FND, COVID-19 vaccination can sometimes trigger new-onset FND, FND relapse, or FND exacerbation.