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2.
Addict Biol ; 29(7): e13423, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38949205

ABSTRACT

In recent years, electronic cigarettes (e-cigs) have gained popularity as stylish, safe, and effective smoking cessation aids, leading to widespread consumer acceptance. Although previous research has explored the acute effects of combustible cigarettes or nicotine replacement therapy on brain functional activities, studies on e-cigs have been limited. Using fNIRS, we conducted graph theory analysis on the resting-state functional connectivity of 61 male abstinent smokers both before and after vaping e-cigs. And we performed Pearson correlation analysis to investigate the relationship between alterations in network metrics and changes in craving. E-cig use resulted in increased degree centrality, nodal efficiency, and local efficiency within the executive control network (ECN), while causing a decrease in these properties within the default model network (DMN). These alterations were found to be correlated with reductions in craving, indicating a relationship between differing network topologies in the ECN and DMN and decreased craving. These findings suggest that the impact of e-cig usage on network topologies observed in male smokers resembles the effects observed with traditional cigarettes and other forms of nicotine delivery, providing valuable insights into their addictive potential and effectiveness as aids for smoking cessation.


Subject(s)
Craving , Electronic Nicotine Delivery Systems , Executive Function , Spectroscopy, Near-Infrared , Vaping , Humans , Male , Adult , Executive Function/drug effects , Executive Function/physiology , Young Adult , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging , Brain/physiopathology , Brain/diagnostic imaging , Brain/drug effects , Smoking Cessation , Nerve Net/physiopathology , Nerve Net/diagnostic imaging , Nerve Net/drug effects
3.
Gut Microbes ; 16(1): 2360233, 2024.
Article in English | MEDLINE | ID: mdl-38949979

ABSTRACT

Functional gastrointestinal disorders (FGIDs), chronic disorders characterized by either abdominal pain, altered intestinal motility, or their combination, have a worldwide prevalence of more than 40% and impose a high socioeconomic burden with a significant decline in quality of life. Recently, FGIDs have been reclassified as disorders of gut-brain interaction (DGBI), reflecting the key role of the gut-brain bidirectional communication in these disorders and their impact on psychological comorbidities. Although, during the past decades, the field of DGBIs has advanced significantly, the molecular mechanisms underlying DGBIs pathogenesis and pathophysiology, and the role of the gut microbiome in these processes are not fully understood. This review aims to discuss the latest body of literature on the complex microbiota-gut-brain interactions and their implications in the pathogenesis of DGBIs. A better understanding of the existing communication pathways between the gut microbiome and the brain holds promise in developing effective therapeutic interventions for DGBIs.


Subject(s)
Brain-Gut Axis , Brain , Gastrointestinal Diseases , Gastrointestinal Microbiome , Gastrointestinal Microbiome/physiology , Humans , Brain-Gut Axis/physiology , Gastrointestinal Diseases/microbiology , Gastrointestinal Diseases/physiopathology , Brain/microbiology , Brain/physiopathology , Animals , Gastrointestinal Tract/microbiology
4.
Transl Psychiatry ; 14(1): 268, 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38951513

ABSTRACT

The urgency of addressing common mental disorders (bipolar disorder, attention-deficit hyperactivity disorder (ADHD), and schizophrenia) arises from their significant societal impact. Developing strategies to support psychiatrists is crucial. Previous studies focused on the relationship between these disorders and changes in the resting-state functional connectome's modularity, often using static functional connectivity (sFC) estimation. However, understanding the dynamic reconfiguration of resting-state brain networks with rich temporal structure is essential for comprehending neural activity and addressing mental health disorders. This study proposes an unsupervised approach combining spatial and temporal characterization of brain networks to classify common mental disorders using fMRI timeseries data from two cohorts (N = 408 participants). We employ the weighted stochastic block model to uncover mesoscale community architecture differences, providing insights into network organization. Our approach overcomes sFC limitations and biases in community detection algorithms by modelling the functional connectome's temporal dynamics as a landscape, quantifying temporal stability at whole-brain and network levels. Findings reveal individuals with schizophrenia exhibit less assortative community structure and participate in multiple motif classes, indicating less specialized network organization. Patients with schizophrenia and ADHD demonstrate significantly reduced temporal stability compared to healthy controls. This study offers insights into functional connectivity (FC) patterns' spatiotemporal organization and their alterations in common mental disorders, highlighting the potential of temporal stability as a biomarker.


Subject(s)
Attention Deficit Disorder with Hyperactivity , Brain , Connectome , Magnetic Resonance Imaging , Nerve Net , Schizophrenia , Humans , Schizophrenia/physiopathology , Schizophrenia/diagnostic imaging , Attention Deficit Disorder with Hyperactivity/physiopathology , Attention Deficit Disorder with Hyperactivity/diagnostic imaging , Female , Male , Adult , Brain/physiopathology , Brain/diagnostic imaging , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Bipolar Disorder/physiopathology , Bipolar Disorder/diagnostic imaging , Young Adult , Middle Aged , Mental Disorders/physiopathology , Mental Disorders/diagnostic imaging
5.
Sci Rep ; 14(1): 15154, 2024 07 02.
Article in English | MEDLINE | ID: mdl-38956297

ABSTRACT

Historically, the analysis of stimulus-dependent time-frequency patterns has been the cornerstone of most electroencephalography (EEG) studies. The abnormal oscillations in high-frequency waves associated with psychotic disorders during sensory and cognitive tasks have been studied many times. However, any significant dissimilarity in the resting-state low-frequency bands is yet to be established. Spectral analysis of the alpha and delta band waves shows the effectiveness of stimulus-independent EEG in identifying the abnormal activity patterns of pathological brains. A generalized model incorporating multiple frequency bands should be more efficient in associating potential EEG biomarkers with first-episode psychosis (FEP), leading to an accurate diagnosis. We explore multiple machine-learning methods, including random-forest, support vector machine, and Gaussian process classifier (GPC), to demonstrate the practicality of resting-state power spectral density (PSD) to distinguish patients of FEP from healthy controls. A comprehensive discussion of our preprocessing methods for PSD analysis and a detailed comparison of different models are included in this paper. The GPC model outperforms the other models with a specificity of 95.78% to show that PSD can be used as an effective feature extraction technique for analyzing and classifying resting-state EEG signals of psychiatric disorders.


Subject(s)
Electroencephalography , Psychotic Disorders , Support Vector Machine , Humans , Psychotic Disorders/physiopathology , Psychotic Disorders/diagnosis , Electroencephalography/methods , Female , Male , Adult , Young Adult , Rest/physiology , Machine Learning , Brain/physiopathology , Adolescent , Signal Processing, Computer-Assisted
6.
Trials ; 25(1): 441, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38956594

ABSTRACT

BACKGROUND: Major depressive disorder (MDD) is a leading cause of disability worldwide across domains of health and cognition, affecting overall quality of life. Approximately one third of individuals with depression do not fully respond to treatments (e.g., conventional antidepressants, psychotherapy) and alternative strategies are needed. Recent early phase trials suggest psilocybin may be a safe and efficacious intervention with rapid-acting antidepressant properties. Psilocybin is thought to exert therapeutic benefits by altering brain network connectivity and inducing neuroplastic changes that endure for weeks post-treatment. Although early clinical results are encouraging, psilocybin's acute neurobiological effects on neuroplasticity have not been fully investigated. We aim to examine for the first time how psilocybin acutely (intraday) and subacutely (weeks) alters functional brain networks implicated in depression. METHODS: Fifty participants diagnosed with MDD or persistent depressive disorder (PDD) will be recruited from a tertiary mood disorders clinic and undergo 1:1 randomization into either an experimental or control arm. Participants will be given either 25 mg psilocybin or 25 mg microcrystalline cellulose (MCC) placebo for the first treatment. Three weeks later, those in the control arm will transition to receiving 25 mg psilocybin. We will investigate whether treatments are associated with changes in arterial spin labelling and blood oxygenation level-dependent contrast neuroimaging assessments at acute and subacute timepoints. Primary outcomes include testing whether psilocybin demonstrates acute changes in (1) cerebral blood flow and (2) functional brain activity in networks associated with mood regulation and depression when compared to placebo, along with changes in MADRS score over time compared to placebo. Secondary outcomes include changes across complementary clinical psychiatric, cognitive, and functional scales from baseline to final follow-up. Serum peripheral neurotrophic and inflammatory biomarkers will be collected at baseline and follow-up to examine relationships with clinical response, and neuroimaging measures. DISCUSSION: This study will investigate the acute and additive subacute neuroplastic effects of psilocybin on brain networks affected by depression using advanced serial neuroimaging methods. Results will improve our understanding of psilocybin's antidepressant mechanisms versus placebo response and whether biological measures of brain function can provide early predictors of treatment response. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT06072898. Registered on 6 October 2023.


Subject(s)
Affect , Brain , Depressive Disorder, Major , Psilocybin , Randomized Controlled Trials as Topic , Humans , Psilocybin/therapeutic use , Psilocybin/adverse effects , Psilocybin/administration & dosage , Psilocybin/pharmacology , Affect/drug effects , Brain/diagnostic imaging , Brain/drug effects , Brain/physiopathology , Depressive Disorder, Major/drug therapy , Magnetic Resonance Imaging , Time Factors , Treatment Outcome , Adult , Neuronal Plasticity/drug effects , Young Adult , Male , Antidepressive Agents/therapeutic use , Female , Middle Aged
7.
BMC Neurosci ; 25(1): 30, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965489

ABSTRACT

BACKGROUND: Alzheimer's disease (AD) and frontotemporal dementia (FTD) are the two most common neurodegenerative dementias, presenting with similar clinical features that challenge accurate diagnosis. Despite extensive research, the underlying pathophysiological mechanisms remain unclear, and effective treatments are limited. This study aims to investigate the alterations in brain network connectivity associated with AD and FTD to enhance our understanding of their pathophysiology and establish a scientific foundation for their diagnosis and treatment. METHODS: We analyzed preprocessed electroencephalogram (EEG) data from the OpenNeuro public dataset, comprising 36 patients with AD, 23 patients with FTD, and 29 healthy controls (HC). Participants were in a resting state with eyes closed. We estimated the average functional connectivity using the Phase Lag Index (PLI) for lower frequencies (delta and theta) and the Amplitude Envelope Correlation with leakage correction (AEC-c) for higher frequencies (alpha, beta, and gamma). Graph theory was applied to calculate topological parameters, including mean node degree, clustering coefficient, characteristic path length, global and local efficiency. A permutation test was then utilized to assess changes in brain network connectivity in AD and FTD based on these parameters. RESULTS: Both AD and FTD patients showed increased mean PLI values in the theta frequency band, along with increases in average node degree, clustering coefficient, global efficiency, and local efficiency. Conversely, mean AEC-c values in the alpha frequency band were notably diminished, which was accompanied by decreases average node degree, clustering coefficient, global efficiency, and local efficiency. Furthermore, AD patients in the occipital region showed an increase in theta band node degree and decreased alpha band clustering coefficient and local efficiency, a pattern not observed in FTD. CONCLUSIONS: Our findings reveal distinct abnormalities in the functional network topology and connectivity in AD and FTD, which may contribute to a better understanding of the pathophysiological mechanisms of these diseases. Specifically, patients with AD demonstrated a more widespread change in functional connectivity, while those with FTD retained connectivity in the occipital lobe. These observations could provide valuable insights for developing electrophysiological markers to differentiate between the two diseases.


Subject(s)
Alzheimer Disease , Brain , Electroencephalography , Frontotemporal Dementia , Humans , Frontotemporal Dementia/physiopathology , Alzheimer Disease/physiopathology , Female , Male , Aged , Electroencephalography/methods , Brain/physiopathology , Middle Aged , Nerve Net/physiopathology , Nerve Net/diagnostic imaging , Neural Pathways/physiopathology
8.
Medicine (Baltimore) ; 103(27): e38707, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38968538

ABSTRACT

BACKGROUND: Jin's three needle (JTN) is a commonly utilized treatment for ischemic stroke in China. Mirror therapy (MT) is also gradually transitioning from treating limb discomfort to restoring motor function in the damaged limb. Investigations into the 2 treatments' mechanisms of action are still ongoing. We used functional magnetic resonance imaging (fMRI) technique in this study to examine the effects of JTN combined with mirror therapy MT on brain function in patients with upper limb dysfunction in ischemic stroke, as well as potential central mechanisms. The goal was to provide a solid evidence-based medical basis to support the continued use of JTN combination MT. METHODS: This study will be a single-blind, randomized, and controlled experiment. Randomization was used to assign 20 patients who met the study's eligibility requirements to the JTN + MT treatment group or the JTN control group. Each intervention will last for 4 weeks, with 6 days of treatment per week. The JTN acupuncture points are 3 temporal acupuncture points on the opposite side of the wounded limb, 3 hand acupuncture points on the injured upper limb, 3 shoulder acupuncture points, Renzhong and Baihui, The (JTN + MT) group simultaneously takes MT for 30 minutes. fMRI of the brain using BOLD and T1-weighted images was done both before and after therapy. Brain areas exhibiting changes in regional homogeneity during the pre and posttreatment periods were analyzed. RESULTS: By the end of the treatment course, Jin three-needle therapy plus MT activated more relevant brain functional regions and increased cerebral blood oxygen perfusion than Jin three-needle therapy alone (P <.05). CONCLUSION: In patients with upper limb impairment following an ischemic stroke, JTN with MT may improve brain function reconstruction in the relevant areas.


Subject(s)
Acupuncture Therapy , Ischemic Stroke , Magnetic Resonance Imaging , Upper Extremity , Humans , Upper Extremity/physiopathology , Single-Blind Method , Ischemic Stroke/physiopathology , Ischemic Stroke/therapy , Ischemic Stroke/diagnostic imaging , Acupuncture Therapy/methods , Magnetic Resonance Imaging/methods , Male , Female , Middle Aged , Brain/diagnostic imaging , Brain/physiopathology , Stroke Rehabilitation/methods , Stroke Rehabilitation/instrumentation , Aged , Adult , Needles , Treatment Outcome
9.
Cereb Cortex ; 34(7)2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38960703

ABSTRACT

Schizophrenia, as a chronic and persistent disorder, exhibits working memory deficits across various stages of the disorder, yet the neural mechanisms underlying these deficits remain elusive with inconsistent neuroimaging findings. We aimed to compare the brain functional changes of working memory in patients at different stages: clinical high risk, first-episode psychosis, and long-term schizophrenia, using meta-analyses of functional magnetic resonance imaging studies. Following a systematic literature search, 56 whole-brain task-based functional magnetic resonance imaging studies (15 for clinical high risk, 16 for first-episode psychosis, and 25 for long-term schizophrenia) were included. The separate and pooled neurofunctional mechanisms among clinical high risk, first-episode psychosis, and long-term schizophrenia were generated by Seed-based d Mapping toolbox. The clinical high risk and first-episode psychosis groups exhibited overlapping hypoactivation in the right inferior parietal lobule, right middle frontal gyrus, and left superior parietal lobule, indicating key lesion sites in the early phase of schizophrenia. Individuals with first-episode psychosis showed lower activation in left inferior parietal lobule than those with long-term schizophrenia, reflecting a possible recovery process or more neural inefficiency. We concluded that SCZ represent as a continuum in the early stage of illness progression, while the neural bases are inversely changed with the development of illness course to long-term course.


Subject(s)
Brain , Magnetic Resonance Imaging , Memory, Short-Term , Schizophrenia , Humans , Memory, Short-Term/physiology , Schizophrenia/physiopathology , Schizophrenia/diagnostic imaging , Brain/physiopathology , Brain/diagnostic imaging , Disease Progression , Memory Disorders/physiopathology , Memory Disorders/etiology , Memory Disorders/diagnostic imaging , Schizophrenic Psychology , Brain Mapping
10.
Elife ; 122024 Jul 08.
Article in English | MEDLINE | ID: mdl-38976325

ABSTRACT

In patients suffering absence epilepsy, recurring seizures can significantly decrease their quality of life and lead to yet untreatable comorbidities. Absence seizures are characterized by spike-and-wave discharges on the electroencephalogram associated with a transient alteration of consciousness. However, it is still unknown how the brain responds to external stimuli during and outside of seizures. This study aimed to investigate responsiveness to visual and somatosensory stimulation in Genetic Absence Epilepsy Rats from Strasbourg (GAERS), a well-established rat model for absence epilepsy. Animals were imaged under non-curarized awake state using a quiet, zero echo time, functional magnetic resonance imaging (fMRI) sequence. Sensory stimulations were applied during interictal and ictal periods. Whole-brain hemodynamic responses were compared between these two states. Additionally, a mean-field simulation model was used to explain the changes of neural responsiveness to visual stimulation between states. During a seizure, whole-brain responses to both sensory stimulations were suppressed and spatially hindered. In the cortex, hemodynamic responses were negatively polarized during seizures, despite the application of a stimulus. The mean-field simulation revealed restricted propagation of activity due to stimulation and agreed well with fMRI findings. Results suggest that sensory processing is hindered or even suppressed by the occurrence of an absence seizure, potentially contributing to decreased responsiveness during this absence epileptic process.


Subject(s)
Brain , Electroencephalography , Epilepsy, Absence , Magnetic Resonance Imaging , Animals , Rats , Epilepsy, Absence/physiopathology , Brain/physiopathology , Brain/diagnostic imaging , Male , Wakefulness/physiology , Disease Models, Animal , Seizures/physiopathology , Photic Stimulation
11.
Neurology ; 103(3): e209524, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-38981074

ABSTRACT

BACKGROUND AND OBJECTIVES: Temporal lobe epilepsy (TLE) is assumed to follow a steady course that is similar across patients. To date, phenotypic and temporal diversities of TLE evolution remain unknown. In this study, we aimed at simultaneously characterizing these sources of variability based on cross-sectional data. METHODS: We studied consecutive patients with TLE referred for evaluation by neurologists to the Montreal Neurological Institute epilepsy clinic, who underwent in-patient video EEG monitoring and multimodal imaging at 3 Tesla, comprising 3D T1 and fluid-attenuated inversion recovery and 2D diffusion-weighted MRI. The cohort included patients with drug-resistant epilepsy and patients with drug-responsive epilepsy. The neuropsychological evaluation included Wechsler Adult Intelligence Scale-III and Leonard tapping task. The control group consisted of participants without TLE recruited through advertisement and who underwent the same MRI acquisition as patients. Based on surface-based analysis of key MRI markers of pathology (gray matter morphology and white matter microstructure), the Subtype and Stage Inference algorithm estimated subtypes and stages of brain pathology to which individual patients were assigned. The number of subtypes was determined by running the algorithm 100 times and estimating mean and SD of disease trajectories and the consistency of patients' assignments based on 1,000 bootstrap samples. Effect of normal aging was subtracted from patients. We examined associations with clinical and cognitive parameters and utility for individualized predictions. RESULTS: We studied 82 patients with TLE (52 female, mean age 35 ± 10 years; 11 drug-responsive) and 41 control participants (23 male, mean age 32 ± 8 years). Among 57 operated, 43/37/20 had Engel-I outcome/hippocampal sclerosis/hippocampal isolated gliosis, respectively. We identified 3 trajectory subtypes: S1 (n = 35), led by ipsilateral hippocampal atrophy and gliosis, followed by white-matter damage; S2 (n = 27), characterized by bilateral neocortical atrophy, followed by ipsilateral hippocampal atrophy and gliosis; and S3 (n = 20), typified by bilateral limbic white-matter damage, followed by bilateral hippocampal gliosis. Patients showed high assignability to their subtypes and stages (>90% bootstrap agreement). S1 had the highest proportions of patients with early disease onset (effect size d = 0.27 vs S2, d = 0.73 vs S3), febrile convulsions (χ2 = 3.70), drug resistance (χ2 = 2.94), a positive MRI (χ2 = 8.42), hippocampal sclerosis (χ2 = 7.57), and Engel-I outcome (χ2 = 1.51), pFDR < 0.05 across all comparisons. S2 and S3 exhibited the intermediate and lowest proportions, respectively. Verbal IQ and digit span were lower in S1 (d = 0.65 and d = 0.50, pFDR < 0.05) and S2 (d = 0.76 and d = 1.09, pFDR < 0.05), compared with S3. We observed progressive decline in sequential motor tapping in S1 and S3 (T = -3.38 and T = -4.94, pFDR = 0.027), compared with S2 (T = 2.14, pFDR = 0.035). S3 showed progressive decline in digit span (T = -5.83, p = 0.021). Supervised classifiers trained on subtype and stage outperformed subtype-only and stage-only models predicting drug response in 73% ± 1.0% (vs 70% ± 1.4% and 63% ± 1.3%) and 76% ± 1.6% for Engel-I outcome (vs 71% ± 0.8% and 72% ± 1.1%), pFDR < 0.05 across all comparisons. DISCUSSION: Cross-sectional MRI-derived models provide reliable prognostic markers of TLE disease evolution, which follows distinct trajectories, each associated with divergent patterns of hippocampal and whole-brain structural alterations, as well as cognitive and clinical profiles.


Subject(s)
Disease Progression , Epilepsy, Temporal Lobe , Magnetic Resonance Imaging , Humans , Epilepsy, Temporal Lobe/diagnostic imaging , Epilepsy, Temporal Lobe/physiopathology , Female , Male , Adult , Middle Aged , Cross-Sectional Studies , Electroencephalography , Brain/diagnostic imaging , Brain/pathology , Brain/physiopathology , Drug Resistant Epilepsy/diagnostic imaging , Drug Resistant Epilepsy/physiopathology , Drug Resistant Epilepsy/pathology , Young Adult , White Matter/diagnostic imaging , White Matter/pathology , Gray Matter/diagnostic imaging , Gray Matter/pathology , Neuropsychological Tests
13.
Int J Hyperthermia ; 41(1): 2376678, 2024.
Article in English | MEDLINE | ID: mdl-38991553

ABSTRACT

PURPOSE: To investigate how passive hyperthermia affect the resting-state functional brain activity based on an acute mouse model after heat stress exposure. MATERIALS AND METHODS: Twenty-eight rs-fMRI data of C57BL/6J male mice which weighing about 24 ∼ 29 g and aged 12 ∼ 16 weeks were collected. The mice in the hyperthermia group (HT, 40 °C ± 0.5 °C, 40 min) were subjected to passive hyperthermia before the anesthesia preparation for scanning. While the normal control group (NC) was subjected to normothermia condition (NC, 20 °C ± 2 °C, 40 min). After data preprocessing, we performed independent component analysis (ICA) and region of interested (ROI)-ROI functional connectivity (FC) analyses on the data of both HT (n = 13) and NC (n = 15). RESULTS: The group ICA analysis showed that the HT and the NC both included 11 intrinsic connectivity networks (ICNs), and can be divided into four types of networks: the cortical network (CN), the subcortical network (SN), the default mode network (DMN), and cerebellar networks. CN and SN belongs to sensorimotor network. Compared with NC, the functional network organization of ICNs in the HT was altered and the overall functional intensity was decreased. Furthermore, 13 ROIs were selected in CN, SN, and DMN for further ROI-ROI FC analysis. The ROI-ROI FC analysis showed that passive hyperthermia exposure significantly reduced the FC strength in the overall brain represented by CN, SN, DMN of mice. CONCLUSION: Prolonged exposure to high temperature has a greater impact on the overall perception and cognitive level of mice, which might help understand the relationship between neuronal activities and physiological thermal sensation and regulation as well as behavioral changes.


Subject(s)
Brain , Hyperthermia , Mice, Inbred C57BL , Animals , Mice , Male , Brain/physiopathology , Brain/diagnostic imaging , Hyperthermia/physiopathology , Magnetic Resonance Imaging/methods
14.
Arq Neuropsiquiatr ; 82(7): 1-11, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38977265

ABSTRACT

BACKGROUND: Alzheimer disease (AD) leads to cognitive decline and alters functional connectivity (FC) in key brain regions. Resting-state functional magnetic resonance imaging (rs-fMRI) assesses these changes using static-FC for overall correlation and dynamic-FC for temporal variability. OBJECTIVE: In AD, there is altered FC compared to normal conditions. The present study investigates possible region-specific functional abnormalities occurring longitudinally over 1 year. Our aim is to evaluate the potential usefulness of the static and dynamic approaches in identifying biomarkers of AD progression. METHODS: The study involved 15 AD and 20 healthy participants from the Alzheimer's Disease Neuroimaging Initiative 2 (ADNI2) database, tracked over 2 visits within 1 year. Using constrained-independent component analysis, we assessed FC changes across 80-regions of interest in AD over the year, examining both static and dynamic conditions. RESULTS: The average regional FC decreased in AD compared to healthy subjects at baseline and after 1 year. The dynamic condition identifies similarities with a few additional changes in the FC compared to the static condition. In both analyses, the baseline assessment revealed reduced connectivity between the following regions: right-middle-occipital and left-superior-occipital, left-hippocampus and right-postcentral, left-lingual and left-fusiform, and precuneus and left-thalamus. Additionally, increased connectivity was found between the left-superior-occipital and precuneus regions. In the 1-year AD assessment, increased connectivity was noted between the right-superior-temporal-pole and right-insular, right-hippocampus and left-caudate, right-middle-occipital and right-superior-temporal-pole, and posterior-cingulate-cortex and middle-temporal-pole regions. CONCLUSION: Significant changes were observed at baseline in the frontal, occipital, and core basal-ganglia regions, progressing towards the temporal lobe and subcortical regions in the following year. After 1 year, we observed the aforementioned region-specific neurological differences in AD, significantly aiding diagnosis and disease tracking.


ANTECEDENTES: A doença de Alzheimer (DA) leva ao declínio cognitivo e altera a conectividade funcional (CF) em regiões-chave do cérebro. A ressonância magnética funcional em estado de repouso (rs-fMRI) avalia essas alterações usando CF estática para correlação geral e CF dinâmica para variabilidade temporal. OBJETIVO: Na DA, há CF alterada em relação às condições normais. O presente estudo investiga possíveis anormalidades funcionais específicas da região que ocorrem longitudinalmente ao longo de um ano. Nosso objetivo é avaliar a utilidade potencial das abordagens estáticas e dinâmicas na identificação de biomarcadores da progressão da DA. MéTODOS: O estudo envolveu 15 participantes com DA e 20 participantes saudáveis do banco de dados da Iniciativa de Neuroimagem da Doença de Alzheimer 2 (ADNI2), rastreados em duas visitas no período de um ano. Usando análise de componentes independentes e restritos, avaliamos as mudanças de CF em 80 regiões de interesse na DA ao longo do ano, examinando condições estáticas e dinâmicas. RESULTADOS: A CF regional média diminuiu na DA em comparação com indivíduos saudáveis no início do estudo e após um ano. A condição dinâmica identifica semelhanças com algumas alterações adicionais na CF em comparação com a condição estática. Em ambas as análises, a avaliação inicial revelou conectividade reduzida entre as seguintes regiões: occipital médio direito e occipital superior esquerdo, hipocampo esquerdo e pós-central direito, lingual esquerdo e fusiforme esquerdo, e precuneus e tálamo esquerdo. Além disso, foi encontrada maior conectividade entre as regiões occipital superior esquerda e precuneus. Na avaliação de DA de um ano, foi observada conectividade aumentada entre o polo temporal superior direito e o insular direito, o hipocampo direito e o caudado esquerdo, occipital médio direito e o polo temporal superior direito, e regiões posteriores do córtex cingulado e do polo temporal médio. CONCLUSãO: Mudanças significativas foram observadas no início do estudo nas regiões frontal, occipital e dos gânglios basais centrais, progredindo em direção ao lobo temporal e regiões subcorticais no ano seguinte. Após um ano, observamos as diferenças neurológicas específicas da região acima mencionadas na DA, auxiliando significativamente no diagnóstico e no rastreamento da doença.


Subject(s)
Alzheimer Disease , Brain , Magnetic Resonance Imaging , Humans , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/physiopathology , Longitudinal Studies , Male , Female , Aged , Brain/diagnostic imaging , Brain/physiopathology , Disease Progression , Case-Control Studies , Aged, 80 and over , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/physiopathology , Brain Mapping/methods , Middle Aged
15.
Commun Biol ; 7(1): 851, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38992101

ABSTRACT

In autism spectrum disorder (ASD), atypical sensory experiences are often associated with irregularities in predictive coding, which proposes that the brain creates hierarchical sensory models via a bidirectional process of predictions and prediction errors. However, it remains unclear how these irregularities manifest across different functional hierarchies in the brain. To address this, we study a marmoset model of ASD induced by valproic acid (VPA) treatment. We record high-density electrocorticography (ECoG) during an auditory task with two layers of temporal control, and applied a quantitative model to quantify the integrity of predictive coding across two distinct hierarchies. Our results demonstrate a persistent pattern of sensory hypersensitivity and unstable predictions across two brain hierarchies in VPA-treated animals, and reveal the associated spatio-spectro-temporal neural signatures. Despite the regular occurrence of imprecise predictions in VPA-treated animals, we observe diverse configurations of underestimation or overestimation of sensory regularities within the hierarchies. Our results demonstrate the coexistence of the two primary Bayesian accounts of ASD: overly-precise sensory observations and weak prior beliefs, and offer a potential multi-layered biomarker for ASD, which could enhance our understanding of its diverse symptoms.


Subject(s)
Autism Spectrum Disorder , Brain , Callithrix , Disease Models, Animal , Animals , Autism Spectrum Disorder/physiopathology , Autism Spectrum Disorder/chemically induced , Brain/physiopathology , Brain/drug effects , Male , Valproic Acid/pharmacology , Electrocorticography
16.
Sci Rep ; 14(1): 16020, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38992236

ABSTRACT

Patients with degenerative cervical myelopathy (DCM) experience structural and functional brain reorganization. However, few studies have investigated the influence of sex on cerebral alterations. The present study investigates the role of sex on brain functional connectivity (FC) and global network topology in DCM and healthy controls (HCs). The resting-state functional MRI data was acquired for 100 patients (58 males vs. 42 females). ROI-to-ROI FC and network topological features were characterized for each patient and HC. Group differences in FC and network topological features were examined. Compared to healthy counterparts, DCM males exhibited higher FC between vision-related brain regions, and cerebellum, brainstem, and thalamus, but lower FC between the intracalcarine cortex and frontal and somatosensory cortices, while DCM females demonstrated higher FC between the thalamus and cerebellar and sensorimotor regions, but lower FC between sensorimotor and visual regions. DCM males displayed higher FC within the cerebellum and between the posterior cingulate cortex (PCC) and vision-related regions, while DCM females displayed higher FC between frontal regions and the PCC, cerebellum, and visual regions. Additionally, DCM males displayed significantly greater intra-network connectivity and efficiency compared to healthy counterparts. Results from the present study imply sex-specific supraspinal functional alterations occur in patients with DCM.


Subject(s)
Magnetic Resonance Imaging , Humans , Female , Male , Middle Aged , Magnetic Resonance Imaging/methods , Spinal Cord Diseases/physiopathology , Spinal Cord Diseases/diagnostic imaging , Nerve Net/physiopathology , Nerve Net/diagnostic imaging , Aged , Brain/physiopathology , Brain/diagnostic imaging , Adult , Sex Characteristics , Brain Mapping/methods , Neural Pathways/physiopathology , Sex Factors , Case-Control Studies
17.
Hum Brain Mapp ; 45(10): e26720, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38994740

ABSTRACT

Electro/Magneto-EncephaloGraphy (EEG/MEG) source imaging (EMSI) of epileptic activity from deep generators is often challenging due to the higher sensitivity of EEG/MEG to superficial regions and to the spatial configuration of subcortical structures. We previously demonstrated the ability of the coherent Maximum Entropy on the Mean (cMEM) method to accurately localize the superficial cortical generators and their spatial extent. Here, we propose a depth-weighted adaptation of cMEM to localize deep generators more accurately. These methods were evaluated using realistic MEG/high-density EEG (HD-EEG) simulations of epileptic activity and actual MEG/HD-EEG recordings from patients with focal epilepsy. We incorporated depth-weighting within the MEM framework to compensate for its preference for superficial generators. We also included a mesh of both hippocampi, as an additional deep structure in the source model. We generated 5400 realistic simulations of interictal epileptic discharges for MEG and HD-EEG involving a wide range of spatial extents and signal-to-noise ratio (SNR) levels, before investigating EMSI on clinical HD-EEG in 16 patients and MEG in 14 patients. Clinical interictal epileptic discharges were marked by visual inspection. We applied three EMSI methods: cMEM, depth-weighted cMEM and depth-weighted minimum norm estimate (MNE). The ground truth was defined as the true simulated generator or as a drawn region based on clinical information available for patients. For deep sources, depth-weighted cMEM improved the localization when compared to cMEM and depth-weighted MNE, whereas depth-weighted cMEM did not deteriorate localization accuracy for superficial regions. For patients' data, we observed improvement in localization for deep sources, especially for the patients with mesial temporal epilepsy, for which cMEM failed to reconstruct the initial generator in the hippocampus. Depth weighting was more crucial for MEG (gradiometers) than for HD-EEG. Similar findings were found when considering depth weighting for the wavelet extension of MEM. In conclusion, depth-weighted cMEM improved the localization of deep sources without or with minimal deterioration of the localization of the superficial sources. This was demonstrated using extensive simulations with MEG and HD-EEG and clinical MEG and HD-EEG for epilepsy patients.


Subject(s)
Electroencephalography , Entropy , Magnetoencephalography , Humans , Magnetoencephalography/methods , Electroencephalography/methods , Adult , Female , Male , Computer Simulation , Young Adult , Epilepsy/physiopathology , Epilepsy/diagnostic imaging , Middle Aged , Brain Mapping/methods , Brain/diagnostic imaging , Brain/physiopathology , Hippocampus/diagnostic imaging , Hippocampus/physiopathology , Models, Neurological
20.
Zhongguo Zhen Jiu ; 44(7): 740-8, 2024 Jul 12.
Article in Chinese | MEDLINE | ID: mdl-38986585

ABSTRACT

OBJECTIVE: To observe the clinical effect of "brain-gut coherence" method of acupuncture on cerebral ischemic stroke (CIS) and explore its action mechanism. METHODS: A total of 82 patients with CIS were randomly divided into an observation group (41 cases, 3 cases dropped out, 2 cases discontinued) and a control group (41 cases, 4 cases dropped out, 2 cases excluded). The conventional basic treatment was administered in the two groups. Additionally, in the observation group, "brain-gut coherence" method of acupuncture was delivered. The stimulating points included the parietal and temporal anterior oblique line on the affected side, Zhongwan (CV 12), Guanyuan (CV 4), and bilateral Tianshu (ST 25), Zusanli (ST 36), Shangjuxu (ST 37) and Xiajuxu (ST 39). In the control group, the routine acupuncture was operated at Baihui (GV 20), Yintang (GV 24+), bilateral Fengchi (GB 20) and Zusanli (ST 36), and Hegu (LI 4), Jianyu (LI 15), Quchi (LI 11), Waiguan (TE 5), Futu (ST 32), Sanyinjiao (SP 6) and Taichong (LR 3) on the affected side. Acupuncture stimulation lasted 30 min each time, once daily, and for 5 days a week. The intervention for 4 weeks was required. The scores of Fugl-Meyer assessment scale (FMA), Berg balance scale (BBS) and the modified Barthel index (MBI), as well as the score of gastrointestinal symptoms were compared before and after treatment in the two groups. The neutrophil count (NUE) and the content of the serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) were detected before and after treatment in the two groups. Using 16S rRNA gene sequencing, the structure and relative abundance of intestinal microflora was detected before and after treatment; and with the enzyme linked immunosorbent assay (ELISA) adopted, the levels of intestinal fatty acid-binding protein (iFABP), D-lactate (D-LA), lipopolysaccharide (LPS), lipopolysaccharide binding protein (LBP), tumor necrosis factor-α(TNF-α), interleukin (IL)-1ß and IL-6 in the serum were detected before and after treatment in the two groups. RESULTS: After treatment, the scores of FMA, BBS and MBI were increased (P<0.05), and the scores of gastrointestinal symptoms were decreased (P<0.05) compared with those before treatment in the two groups. Compared with the control group, the scores of FMA, BBS and MBI were higher (P<0.05) and the score of gastrointestinal symptoms was lower (P<0.05) in the observation group after treatment. NEU and the content of serum NT-proBNP were reduced in the two groups (P<0.05), and the content of serum NT-proBNP in the observation group was lower than that of the control group (P<0.05) after treatment. Chao1, Ace, Sobs and Shannon indexes were increased after treatment compared with those before treatment in the two groups (P<0.05); and these indexes in the observation group were higher when compared with the control group (P<0.05). After treatment, the relative abundance of Bacteroidaceae, Enterobacteriaceae, Oscillospiraceae, Streptococcaceae and Sutterellaceae was reduced in comparison with that before treatment in the two groups (P<0.05); and the relative abundance of these microflora was lower in the observation group when compared with the control group (P<0.05). After treatment, the relative abundance of Lachnospiraceae, Ruminococcaceae, Bifidobacteriaceae and Coriobacteriaceae was increased in comparison with that before treatment in the two groups (P<0.05); and the relative abundance of these microflora was elevated in the observation group when compared with the control group (P<0.05). After treatment, the levels of iFABP, D-LA, LPS, LBP, TNF-α, IL-1ß and IL-6 were reduced when compared with those before treatment in the two groups (P<0.05), and these levels of the observation group were lower than those of the control group (P<0.05). CONCLUSION: "Brain-gut coherence" method of acupuncture can improve the motor function and gastrointestinal function of the patients with cerebral ischemic stroke, which may be related to modulating the structure of intestinal microflora, alleviating inflammatory reactions and accelerating the intestinal barrier repair.


Subject(s)
Acupuncture Points , Acupuncture Therapy , Gastrointestinal Microbiome , Ischemic Stroke , Humans , Male , Middle Aged , Female , Aged , Ischemic Stroke/therapy , Ischemic Stroke/physiopathology , Brain/physiopathology , Adult , Treatment Outcome , Motor Activity , Interleukin-6/blood , Tumor Necrosis Factor-alpha/blood
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