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1.
J Neural Eng ; 19(4)2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35797967

RESUMO

Objective. The neurocognitive attention functions involve the cooperation of multiple brain regions, and the defects in the cooperation will lead to attention-deficit/hyperactivity disorder (ADHD), which is one of the most common neuropsychiatric disorders for children. The current ADHD diagnosis is mainly based on a subjective evaluation that is easily biased by the experience of the clinicians and lacks the support of objective indicators. The purpose of this study is to propose a method that can effectively identify children with ADHD.Approach. In this study, we proposed a CNN-LSTM model to solve the three-class problems of classifying ADHD, attention deficit disorder (ADD) and healthy children, based on a public electroencephalogram (EEG) dataset that includes event-related potential (ERP) EEG signals of 144 children. The convolution visualization and saliency map methods were used to observe the features automatically extracted by the proposed model, which could intuitively explain how the model distinguished different groups.Main results. The results showed that our CNN-LSTM model could achieve an accuracy as high as 98.23% in a five-fold cross-validation method, which was significantly better than the current state-of-the-art CNN models. The features extracted by the proposed model were mainly located in the frontal and central areas, with significant differences in the time period mappings among the three different groups. The P300 and contingent negative variation (CNV) in the frontal lobe had the largest decrease in the healthy control (HC) group, and the ADD group had the smallest decrease. In the central area, only the HC group had a significant negative oscillation of CNV waves.Significance. The results of this study suggest that the CNN-LSTM model can effectively identify children with ADHD and its subtypes. The visualized features automatically extracted by this model could better explain the differences in the ERP response among different groups, which is more convincing than previous studies, and it could be used as more reliable neural biomarkers to help with more accurate diagnosis in the clinics.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Modelos Biológicos , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Criança , Eletroencefalografia , Potenciais Evocados/fisiologia , Humanos , Memória de Longo Prazo/fisiologia , Memória de Curto Prazo/fisiologia , Rede Nervosa/fisiopatologia , Reprodutibilidade dos Testes
2.
J Neuroimaging ; 32(6): 1211-1223, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35843726

RESUMO

BACKGROUND AND PURPOSE: Early diagnosis of cognitive impairment is important because symptoms can be delayed through therapies. Synaptic disconnections are the key characteristics of dementia, and through nonlinear complexity analysis of brain function, it is possible to identify long-range synaptic disconnections in the brain. METHODS: We investigated the capability of a novel upper-extremity function (UEF) dual-task paradigm in the functional MRI (fMRI) setting, where the participant flexes and extends their arm while counting, to differentiate between cognitively normal (CN) and those with mild cognitive impairment (MCI). We used multiscale entropy (MSE) complexity analysis of the blood oxygen-level dependent time-series across neural networks and brain regions. Outside of the fMRI, we used the UEF dual-task test, while the elbow kinematics were measured using motion sensors, to record the motor function score. RESULTS: Results showed 34% lower MSE values in MCI compared to CN (p<.04 for all regions and networks except cerebellum when counting down by one; effect size = 1.35±0.15) and a negative correlation between MSE values and age (average r2 of 0.30 for counting down by one and 0.36 for counting backward by three). Results also showed an improvement in the logistic regression model sensitivity by 14-24% in predicting the presence of MCI when brain function measure was added to the motor function score (kinematics data). CONCLUSIONS: Current findings suggest that combining measures of neural network and motor function, in addition to neuropsychological testing, may provide an accurate tool for assessing early-stage cognitive impairment and age-related decline in cognition.


Assuntos
Encéfalo , Disfunção Cognitiva , Atividade Motora , Comportamento Multitarefa , Rede Nervosa , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Cognição/fisiologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Comportamento Multitarefa/fisiologia , Fatores Etários , Sinapses/fisiologia , Transmissão Sináptica/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Rede Nervosa/fisiopatologia , Atividade Motora/fisiologia
3.
Sci Rep ; 12(1): 2969, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35194054

RESUMO

Neuropsychological studies reported that shift workers show reduced cognitive performance and circadian dysfunctions which may impact structural and functional brain networks. Here we tested the hypothesis whether night shift work is associated with resting-state functional connectivity (RSFC), cortical thickness and gray matter volume in participants of the 1000BRAINS study for whom information on night shift work and imaging data were available. 13 PRESENT and 89 FORMER night shift workers as well as 430 control participants who had never worked in shift (NEVER) met these criteria and were included in our study. No associations between night shift work, three graph-theoretical measures of RSFC of 7 functional brain networks and brain morphology were found after multiple comparison correction. Preceding multiple comparison correction, our results hinted at an association between more years of shift work and higher segregation of the visual network in PRESENT shift workers and between shift work experience and lower gray matter volume of the left thalamus. Extensive neuropsychological investigations supplementing objective imaging methodology did not reveal an association between night shift work and cognition after multiple comparison correction. Our pilot study suggests that night shift work does not elicit general alterations in brain networks and affects the brain only to a limited extent. These results now need to be corroborated in studies with larger numbers of participants.


Assuntos
Encéfalo/fisiopatologia , Cognição , Rede Nervosa/fisiopatologia , Jornada de Trabalho em Turnos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
4.
Sci Rep ; 12(1): 1319, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35079038

RESUMO

Synchronization has an important role in neural networks dynamics that is mostly accompanied by cognitive activities such as memory, learning, and perception. These activities arise from collective neural behaviors and are not totally understood yet. This paper aims to investigate a cortical model from this perspective. Historically, epilepsy has been regarded as a functional brain disorder associated with excessive synchronization of large neural populations. Epilepsy is believed to arise as a result of complex interactions between neural networks characterized by dynamic synchronization. In this paper, we investigated a network of neural populations in a way the dynamics of each node corresponded to the Jansen-Rit neural mass model. First, we study a one-column Jansen-Rit neural mass model for four different input levels. Then, we considered a Watts-Strogatz network of Jansen-Rit oscillators. We observed an epileptic activity in the weak input level. The network is considered to change various parameters. The detailed results including the mean time series, phase spaces, and power spectrum revealed a wide range of different behaviors such as epilepsy, healthy, and a transition between synchrony and asynchrony states. In some points of coupling coefficients, there is an abrupt change in the order parameters. Since the critical state is a dynamic candidate for healthy brains, we considered some measures of criticality and investigated them at these points. According to our study, some markers of criticality can occur at these points, while others may not. This occurrence is a result of the nature of the specific order parameter selected to observe these markers. In fact, The definition of a proper order parameter is key and must be defined properly. Our view is that the critical points exhibit clear characteristics and invariance of scale, instead of some types of markers. As a result, these phase transition points are not critical as they show no evidence of scaling invariance.


Assuntos
Córtex Cerebral/fisiologia , Sincronização Cortical/fisiologia , Epilepsia/fisiopatologia , Modelos Neurológicos , Rede Nervosa/fisiologia , Rede Nervosa/fisiopatologia , Ritmo alfa/fisiologia , Cognição/fisiologia , Humanos , Memória/fisiologia , Neurônios/fisiologia , Percepção/fisiologia
5.
PLoS One ; 17(1): e0262310, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34986206

RESUMO

Neonatal brain injury may impact brain development and lead to lifelong functional impairments. Hypoxic-ischemic encephalopathy (HIE) and congenital heart disease (CHD) are two common causes of neonatal brain injury differing in timing and mechanism. Maturation of whole-brain neural networks can be quantified during development using diffusion magnetic resonance imaging (dMRI) in combination with graph theory metrics. DMRI of 35 subjects with CHD and 62 subjects with HIE were compared to understand differences in the effects of HIE and CHD on the development of network topological parameters and functional outcomes. CHD newborns had worse 12-18 month language (P<0.01) and 30 month cognitive (P<0.01), language (P = 0.05), motor outcomes (P = 0.01). Global efficiency, a metric of brain integration, was lower in CHD (P = 0.03) than in HIE, but transitivity, modularity and small-worldness were similar. After controlling for clinical factors known to affect neurodevelopmental outcomes, we observed that global efficiency was highly associated with 30 month motor outcomes (P = 0.02) in both groups. To explore neural correlates of adverse language outcomes in CHD, we used hypothesis-based and data-driven approaches to identify pathways with altered structural connectivity. We found that connectivity strength in the superior longitudinal fasciculus (SLF) tract 2 was inversely associated with expressive language. After false discovery rate correction, a whole connectome edge analysis identified 18 pathways that were hypoconnected in the CHD cohort as compared to HIE. In sum, our study shows that neonatal structural connectivity predicts early motor development after HIE or in subjects with CHD, and regional SLF connectivity is associated with language outcomes. Further research is needed to determine if and how brain networks change over time and whether those changes represent recovery or ongoing dysfunction. This knowledge will directly inform strategies to optimize neurologic functional outcomes after neonatal brain injury.


Assuntos
Lesões Encefálicas/fisiopatologia , Encéfalo/fisiopatologia , Criança , Conectoma/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Cardiopatias Congênitas/fisiopatologia , Humanos , Hipóxia-Isquemia Encefálica/fisiopatologia , Recém-Nascido , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/fisiopatologia , Vias Neurais/fisiopatologia , Estudos Prospectivos
6.
Neural Plast ; 2022: 9941832, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035474

RESUMO

Background: Visual symptoms are common in patients with migraine, even in interictal periods. The purpose was to assess the association between dynamic functional connectivity (dFC) of the visual cortex and clinical characteristics in migraine without aura (MwoA) patients. Methods: We enrolled fifty-five MwoA patients as well as fifty gender- and age-matched healthy controls. Regional visual cortex alterations were investigated using regional homogeneity (ReHo) and amplitude of low-frequency fluctuation (ALFF). Then, significant regions were selected as seeds for conducting dFC between the visual cortex and the whole brain. Results: Relative to healthy controls, MwoA patients exhibited decreased ReHo and ALFF values in the right lingual gyrus (LG) and increased ALFF values in the prefrontal cortex. The right LG showed abnormal dFC within the visual cortex and with other core brain networks. Additionally, ReHo values for the right LG were correlated with duration of disease and ALFF values of the right inferior frontal gyrus and middle frontal gyrus were correlated with headache frequency and anxiety scores, respectively. Moreover, the abnormal dFC of the right LG with bilateral cuneus was positively correlated with anxiety scores. Conclusions: The dFC abnormalities of the visual cortex may be involved in pain integration with multinetworks and associated with anxiety disorder in episodic MwoA patients.


Assuntos
Encéfalo/diagnóstico por imagem , Enxaqueca sem Aura/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Vias Visuais/diagnóstico por imagem , Adulto , Encéfalo/fisiopatologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Enxaqueca sem Aura/fisiopatologia , Rede Nervosa/fisiopatologia , Vias Visuais/fisiopatologia , Adulto Jovem
7.
Cells ; 11(2)2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35053352

RESUMO

For Alzheimer's disease (AD), aging is the main risk factor, but whether cognitive impairments due to aging resemble early AD deficits is not yet defined. When working with mouse models of AD, the situation is just as complicated, because only a few studies track the progression of the disease at different ages, and most ignore how the aging process affects control mice. In this work, we addressed this problem by comparing the aging process of PS2APP (AD) and wild-type (WT) mice at the level of spontaneous brain electrical activity under anesthesia. Using local field potential recordings, obtained with a linear probe that traverses the posterior parietal cortex and the entire hippocampus, we analyzed how multiple electrical parameters are modified by aging in AD and WT mice. With this approach, we highlighted AD specific features that appear in young AD mice prior to plaque deposition or that are delayed at 12 and 16 months of age. Furthermore, we identified aging characteristics present in WT mice but also occurring prematurely in young AD mice. In short, we found that reduction in the relative power of slow oscillations (SO) and Low/High power imbalance are linked to an AD phenotype at its onset. The loss of SO connectivity and cortico-hippocampal coupling between SO and higher frequencies as well as the increase in UP-state and burst durations are found in young AD and old WT mice. We show evidence that the aging process is accelerated by the mutant PS2 itself and discuss such changes in relation to amyloidosis and gliosis.


Assuntos
Envelhecimento/patologia , Doença de Alzheimer/patologia , Potenciais de Ação/fisiologia , Doença de Alzheimer/complicações , Doença de Alzheimer/fisiopatologia , Amiloidose/complicações , Amiloidose/patologia , Amiloidose/fisiopatologia , Animais , Ritmo Delta/fisiologia , Progressão da Doença , Gliose/complicações , Gliose/patologia , Gliose/fisiopatologia , Hipocampo/patologia , Camundongos Endogâmicos C57BL , Rede Nervosa/fisiopatologia , Placa Amiloide/complicações , Placa Amiloide/patologia , Placa Amiloide/fisiopatologia
8.
Brain Res ; 1779: 147787, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35041843

RESUMO

Temporal lobe epilepsy (TLE) is one of the most common focal pharmacotherapy-resistant epilepsy in adults. Previous studies have shown significantly higher numbers of neurons in the neocortical white matter in TLE patients than in controls. The aim of this work was to investigate whether white matter neurons are part of the neuronal circuitry. Therefore, we studied the distribution and density of synapses in surgically resected neocortical tissue of pharmacotherapy-resistant TLE patients. Neocortical white matter of temporal lobe from non-epileptic patients were used as controls. Synapses and neurons were visualized with immunohistochemistry using antibodies against synaptophysin and NeuN, respectively. The presence of synaptophysin in presynaptic terminals was verified by electron microscopy. Quantification of immunostaining was performed and the data of the patients' cognitive tests as well as clinical records were compared to the density of neurons and synapses. Synaptophysin density in the white matter of TLE patients was significantly higher than in controls. In TLE, a significant correlation was found between synaptophysin immunodensity and density of white matter neurons. Neuronal as well as synaptophysin density significantly correlated with scores of verbal memory of TLE patients. Neurosurgical outcome of TLE patients did not significantly correlate with histological data, although, higher neuronal and synaptophysin densities were observed in patients with favorable post-surgical outcome. Our results suggest that white matter neurons in TLE patients receive substantial synaptic input and indicate that white matter neurons may be integrated in epileptic neuronal networks responsible for the development or maintenance of seizures.


Assuntos
Epilepsia Resistente a Medicamentos/fisiopatologia , Epilepsia do Lobo Temporal/fisiopatologia , Neocórtex/fisiopatologia , Rede Nervosa/fisiopatologia , Neurônios/fisiologia , Sinapses/fisiologia , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia do Lobo Temporal/cirurgia , Humanos , Neocórtex/cirurgia , Sinaptofisina/metabolismo , Aprendizagem Verbal/fisiologia , Substância Branca
9.
Sci Rep ; 12(1): 114, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997092

RESUMO

Microglia are subject to change in tandem with the endogenously generated biological oscillations known as our circadian rhythm. Studies have shown microglia harbor an intrinsic molecular clock which regulates diurnal changes in morphology and influences inflammatory responses. In the adult brain, microglia play an important role in the regulation of condensed extracellular matrix structures called perineuronal nets (PNNs), and it has been suggested that PNNs are also regulated in a circadian and diurnal manner. We sought to determine whether microglia mediate the diurnal regulation of PNNs via CSF1R inhibitor dependent microglial depletion in C57BL/6J mice, and how the absence of microglia might affect cortical diurnal gene expression rhythms. While we observe diurnal differences in microglial morphology, where microglia are most ramified at the onset of the dark phase, we do not find diurnal differences in PNN intensity. However, PNN intensity increases across many brain regions in the absence of microglia, supporting a role for microglia in the regulation of PNNs. Here, we also show that cortical diurnal gene expression rhythms are intact, with no cycling gene changes without microglia. These findings demonstrate a role for microglia in the maintenance of PNNs, but not in the maintenance of diurnal rhythms.


Assuntos
Ondas Encefálicas , Ritmo Circadiano , Microglia/patologia , Rede Nervosa/patologia , Córtex Somatossensorial/patologia , Animais , Ondas Encefálicas/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/genética , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/genética , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/metabolismo , Regulação da Expressão Gênica , Masculino , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/metabolismo , Rede Nervosa/fisiopatologia , Compostos Orgânicos/farmacologia , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Córtex Somatossensorial/efeitos dos fármacos , Córtex Somatossensorial/metabolismo , Córtex Somatossensorial/fisiopatologia , Fatores de Tempo
10.
Hum Brain Mapp ; 43(2): 681-699, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655259

RESUMO

Emerging studies corroborate the importance of neuroimaging biomarkers and machine learning to improve diagnostic classification of amyotrophic lateral sclerosis (ALS). While most studies focus on structural data, recent studies assessing functional connectivity between brain regions by linear methods highlight the role of brain function. These studies have yet to be combined with brain structure and nonlinear functional features. We investigate the role of linear and nonlinear functional brain features, and the benefit of combining brain structure and function for ALS classification. ALS patients (N = 97) and healthy controls (N = 59) underwent structural and functional resting state magnetic resonance imaging. Based on key hubs of resting state networks, we defined three feature sets comprising brain volume, resting state functional connectivity (rsFC), as well as (nonlinear) resting state dynamics assessed via recurrent neural networks. Unimodal and multimodal random forest classifiers were built to classify ALS. Out-of-sample prediction errors were assessed via five-fold cross-validation. Unimodal classifiers achieved a classification accuracy of 56.35-61.66%. Multimodal classifiers outperformed unimodal classifiers achieving accuracies of 62.85-66.82%. Evaluating the ranking of individual features' importance scores across all classifiers revealed that rsFC features were most dominant in classification. While univariate analyses revealed reduced rsFC in ALS patients, functional features more generally indicated deficits in information integration across resting state brain networks in ALS. The present work undermines that combining brain structure and function provides an additional benefit to diagnostic classification, as indicated by multimodal classifiers, while emphasizing the importance of capturing both linear and nonlinear functional brain properties to identify discriminative biomarkers of ALS.


Assuntos
Esclerose Amiotrófica Lateral , Encéfalo , Conectoma , Aprendizado Profundo , Imageamento por Ressonância Magnética , Rede Nervosa , Adulto , Idoso , Esclerose Amiotrófica Lateral/classificação , Esclerose Amiotrófica Lateral/diagnóstico por imagem , Esclerose Amiotrófica Lateral/patologia , Esclerose Amiotrófica Lateral/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/fisiopatologia , Conectoma/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Rede Nervosa/fisiopatologia
11.
Hum Brain Mapp ; 43(2): 633-646, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34609038

RESUMO

Neuromodulation treatment effect size for bothersome tinnitus may be larger and more predictable by adopting a target selection approach guided by personalized striatal networks or functional connectivity maps. Several corticostriatal mechanisms are likely to play a role in tinnitus, including the dorsal/ventral striatum and the putamen. We examined whether significant tinnitus treatment response by deep brain stimulation (DBS) of the caudate nucleus may be related to striatal network increased functional connectivity with tinnitus networks that involve the auditory cortex or ventral cerebellum. The first study was a cross-sectional 2-by-2 factorial design (tinnitus, no tinnitus; hearing loss, normal hearing, n = 68) to define cohort level abnormal functional connectivity maps using high-field 7.0 T resting-state fMRI. The second study was a pilot case-control series (n = 2) to examine whether tinnitus modulation response to caudate tail subdivision stimulation would be contingent on individual level striatal connectivity map relationships with tinnitus networks. Resting-state fMRI identified five caudate subdivisions with abnormal cohort level functional connectivity maps. Of those, two connectivity maps exhibited increased connectivity with tinnitus networks-dorsal caudate head with Heschl's gyrus and caudate tail with the ventral cerebellum. DBS of the caudate tail in the case-series responder resulted in dramatic reductions in tinnitus severity and loudness, in contrast to the nonresponder who showed no tinnitus modulation. The individual level connectivity map of the responder was in alignment with the cohort expectation connectivity map, where the caudate tail exhibited increased connectivity with tinnitus networks, whereas the nonresponder individual level connectivity map did not.


Assuntos
Córtex Auditivo/fisiopatologia , Núcleo Caudado/fisiopatologia , Cerebelo/fisiopatologia , Conectoma , Estimulação Encefálica Profunda , Perda Auditiva/fisiopatologia , Rede Nervosa/fisiopatologia , Zumbido/fisiopatologia , Zumbido/terapia , Adulto , Idoso , Córtex Auditivo/diagnóstico por imagem , Estudos de Casos e Controles , Núcleo Caudado/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Estudos Transversais , Feminino , Perda Auditiva/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Zumbido/diagnóstico por imagem
12.
Neurorehabil Neural Repair ; 36(1): 61-68, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34711080

RESUMO

OBJECTIVE: To compare the effects of high-frequency (10 Hz) versus low-frequency (1 Hz) repetitive Transcranial Magnetic Stimulation (rTMS) on motor recovery and functional reorganization of the cortical motor network during the early phase of stroke. METHODS: Forty-six hospitalized, first-ever ischemic stroke patients in early stage (within two weeks) with upper limb motor deficits were recruited. They were randomly allocated to three groups with 10 Hz ipsilesional rTMS, 1 Hz contralesional rTMS, and sham rTMS of five daily session. All patients underwent motor function (Upper Extremity Fugl-Meyer), neurophysiological and resting-state  functional Magnetic Resonance Imaging (fMRI) (rs-fMRI) assessments before and after rTMS intervention. Motor recovery (△Fugl-Meyer Assessment) was defined as motor function changes before and after rTMS intervention. Motor function assessment was reevaluated at time point of three month follow-up. RESULTS: The two real rTMS groups manifested greater motor improvements than the sham group. The effect sustained for at least 3 months after the end of the treatment sessions. Compared with the sham group, 10 Hz ipsilesional rTMS group presented increased resting-state functional connectivity (FC) between ipsilesional primary motor cortex (M1) and contralesional M1 (P = .007), whereas 1 Hz contralesional rTMS group presented increased FC between contralesional M1 and ipsilesional supplementary motor area (P = .010), which were positively correlated with motor recovery (P < .05). CONCLUSION: Beneficial effect of rTMS on motor recovery might be underlaid by increased FC between stimulating site and the remote motor areas, highlighting the motor network reorganization mechanism of rTMS in early post-stroke phase.


Assuntos
Conectoma , Imageamento por Ressonância Magnética , Córtex Motor/fisiopatologia , Rede Nervosa/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Estimulação Magnética Transcraniana , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Avaliação de Resultados em Cuidados de Saúde , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia
13.
Nat Rev Neurosci ; 23(1): 35-52, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34728833

RESUMO

Various environmental stressors, such as extreme temperatures (hot and cold), pathogens, predators and insufficient food, can threaten life. Remarkable progress has recently been made in understanding the central circuit mechanisms of physiological responses to such stressors. A hypothalamomedullary neural pathway from the dorsomedial hypothalamus (DMH) to the rostral medullary raphe region (rMR) regulates sympathetic outflows to effector organs for homeostasis. Thermal and infection stress inputs to the preoptic area dynamically alter the DMH → rMR transmission to elicit thermoregulatory, febrile and cardiovascular responses. Psychological stress signalling from a ventromedial prefrontal cortical area to the DMH drives sympathetic and behavioural responses for stress coping, representing a psychosomatic connection from the corticolimbic emotion circuit to the autonomic and somatic motor systems. Under starvation stress, medullary reticular neurons activated by hunger signalling from the hypothalamus suppress thermogenic drive from the rMR for energy saving and prime mastication to promote food intake. This Perspective presents a combined neural network for environmental stress responses, providing insights into the central circuit mechanism for the integrative regulation of systemic organs.


Assuntos
Hipotálamo/fisiologia , Hipotálamo/fisiopatologia , Bulbo/fisiologia , Bulbo/fisiopatologia , Rede Nervosa/fisiologia , Rede Nervosa/fisiopatologia , Estresse Fisiológico , Estresse Psicológico/fisiopatologia , Animais , Regulação da Temperatura Corporal/fisiologia , Transtornos de Estresse por Calor/fisiopatologia , Humanos , Vias Neurais/fisiologia
14.
Hum Brain Mapp ; 43(2): 581-592, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34729858

RESUMO

Lifelong bilingualism is associated with delayed dementia onset, suggesting a protective effect on the brain. Here, we aim to study the effects of lifelong bilingualism as a dichotomous and continuous phenomenon, on brain metabolism and connectivity in individuals with Alzheimer's dementia. Ninety-eight patients with Alzheimer's dementia (56 monolinguals; 42 bilinguals) from three centers entered the study. All underwent an [18F]-fluorodeoxyglucose positron emission tomography (PET) imaging session. A language background questionnaire measured the level of language use for conversation and reading. Severity of brain hypometabolism and strength of connectivity of the major neurocognitive networks was compared across monolingual and bilingual individuals, and tested against the frequency of second language life-long usage. Age, years of education, and MMSE score were included in all above mentioned analyses as nuisance covariates. Cerebral hypometabolism was more severe in bilingual compared to monolingual patients; severity of hypometabolism positively correlated with the degree of second language use. The metabolic connectivity analyses showed increased connectivity in the executive, language, and anterior default mode networks in bilingual compared to monolingual patients. The change in neuronal connectivity was stronger in subjects with higher second language use. All effects were most pronounced in the left cerebral hemisphere. The neuroprotective effects of lifelong bilingualism act both against neurodegenerative processes and through the modulation of brain networks connectivity. These findings highlight the relevance of lifelong bilingualism in brain reserve and compensation, supporting bilingual education and social interventions aimed at usage, and maintenance of two or more languages, including dialects, especially crucial in the elderly people.


Assuntos
Doença de Alzheimer/fisiopatologia , Córtex Cerebral/fisiopatologia , Conectoma , Multilinguismo , Rede Nervosa/fisiopatologia , Neuroproteção/fisiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Fatores de Proteção
15.
Neurobiol Aging ; 109: 166-175, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34740078

RESUMO

White matter hyperintensities (WMH) are associated with greater falls risk and slow gait speed. Whether these deficits are caused by the disruption of large-scale functional networks remains inconclusive. Further, physical activity moderates the association between WMHs and falls, but whether this extends to the disruption of functional networks remains unknown. One hundred and sixty-four adults (>55 years old) were included in this study. Using lesion network mapping, we identified significant correlations between the percentage of WMH-related disruption of the dorsal attention network and Physiological Profile Assessment (PPA) score (r = 0.24, p < 0.01); and between disruption of both the sensorimotor (r = 0.23, p < 0.01) and ventral attention networks (r = 0.21, p = 0.01) with foam sway. There were no significant associations with floor sway or gait speed. Physical activity moderated the association between the dorsal attention network and PPA score (p = 0.045). Thus, future research should investigate whether physical activity should be recommended in the clinical management of older adults with cerebral small vessel disease.


Assuntos
Acidentes por Quedas , Rede Nervosa/patologia , Substância Branca/patologia , Idoso , Idoso de 80 Anos ou mais , Atenção/fisiologia , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Risco , Córtex Sensório-Motor/fisiologia , Córtex Sensório-Motor/fisiopatologia , Velocidade de Caminhada , Substância Branca/fisiopatologia
16.
Urology ; 159: 133-138, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34688769

RESUMO

OBJECTIVES: To detect seed-based functional connectivity (FC) between various cortical sub-regions and the thalamus in lifelong premature ejaculation (LPE) patients and explore whether specific thalamocortical networks are significantly altered in PE patients compared to healthy controls (HCs) METHODS: Fifty non-medicated LPE patients and 40 age-matched HCs underwent a resting-state functional MRI. FC was adopted to identify specific thalamocortical connectivity between the thalamus and 6 cortical regions of interest (i.e., the motor cortex/supplementary motor, the prefrontal cortex, the temporal lobe, the posterior parietal cortex, the somatosensory cortex and the occipital lobe). In LPE patients, regression analysis was subsequently conducted to assess relationships of thalamocortical connectivity with the Premature Ejaculation Diagnostic Tool (PEDT) score and the Intravaginal Ejaculatory Latency Time (IELT). RESULTS: LPE patients had significantly decreased FC between the motor cortex and bilateral ventral thalamus, between the prefrontal cortex and left dorsomedial thalamus, as well as between the temporal cortex and bilateral ventromedial thalamus. In LPE patients, PEDT score was significantly positively associated with the thalamus-posterior parietal cortex FC, and negatively associated with the thalamus-temporal cortex FC, while IELT was positively associated with the thalamus-temporal cortex and thalamus-motor cortex FC. CONCLUSION: These results enrich the imaging evidence for the understanding of the neurobiological mechanisms and/or consequences of LPE.


Assuntos
Córtex Cerebral , Conectoma/métodos , Rede Nervosa , Ejaculação Precoce , Tálamo , Adulto , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/patologia , Rede Nervosa/fisiopatologia , Neurofisiologia , Ejaculação Precoce/diagnóstico , Ejaculação Precoce/fisiopatologia , Tálamo/diagnóstico por imagem , Tálamo/fisiopatologia
17.
J Clin Endocrinol Metab ; 107(3): e1167-e1180, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34665863

RESUMO

CONTEXT: About one-third of diabetic patients suffer from neuropathic pain, which is poorly responsive to analgesic therapy and associated with greater autonomic dysfunction. Previous research on diabetic neuropathy mainly links pain and autonomic dysfunction to peripheral nerve degeneration resulting from systemic metabolic disturbances, but maladaptive plasticity in the central pain and autonomic systems following peripheral nerve injury has been relatively ignored. OBJECTIVE: This study aimed to investigate how the brain is affected in painful diabetic neuropathy (PDN), in terms of altered structural connectivity (SC) of the thalamus and hypothalamus that are key regions modulating nociceptive and autonomic responses. METHODS: We recruited 25 PDN and 13 painless (PLDN) diabetic neuropathy patients, and 27 healthy adults as controls. The SC of the thalamus and hypothalamus with limbic regions mediating nociceptive and autonomic responses was assessed using diffusion tractography. RESULTS: The PDN patients had significantly lower thalamic and hypothalamic SC of the right amygdala compared with the PLDN and control groups. In addition, lower thalamic SC of the insula was associated with more severe peripheral nerve degeneration, and lower hypothalamic SC of the anterior cingulate cortex was associated with greater autonomic dysfunction manifested by decreased heart rate variability. CONCLUSION: Our findings indicate that alterations in brain structural connectivity could be a form of maladaptive plasticity after peripheral nerve injury, and also demonstrate a pathophysiological association between disconnection of the limbic circuitry and pain and autonomic dysfunction in diabetes.


Assuntos
Neuropatias Diabéticas/fisiopatologia , Hipotálamo/fisiopatologia , Neuralgia/fisiopatologia , Disautonomias Primárias/fisiopatologia , Tálamo/fisiopatologia , Adaptação Fisiológica , Adulto , Idoso , Sistema Nervoso Autônomo/fisiologia , Conectoma , Imagem de Tensor de Difusão , Feminino , Humanos , Hipotálamo/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Vias Neurais/fisiopatologia , Plasticidade Neuronal/fisiologia , Tálamo/diagnóstico por imagem
18.
Hum Brain Mapp ; 43(2): 844-859, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34716740

RESUMO

Sensorimotor abnormalities are common in autism spectrum disorder (ASD) and predictive of functional outcomes, though their neural underpinnings remain poorly understood. Using functional magnetic resonance imaging, we examined both brain activation and functional connectivity during visuomotor behavior in 27 individuals with ASD and 30 typically developing (TD) controls (ages 9-35 years). Participants maintained a constant grip force while receiving visual feedback at three different visual gain levels. Relative to controls, ASD participants showed increased force variability, especially at high gain, and reduced entropy. Brain activation was greater in individuals with ASD than controls in supplementary motor area, bilateral superior parietal lobules, and contralateral middle frontal gyrus at high gain. During motor action, functional connectivity was reduced between parietal-premotor and parietal-putamen in individuals with ASD compared to controls. Individuals with ASD also showed greater age-associated increases in functional connectivity between cerebellum and visual, motor, and prefrontal cortical areas relative to controls. These results indicate that visuomotor deficits in ASD are associated with atypical activation and functional connectivity of posterior parietal, premotor, and striatal circuits involved in translating sensory feedback information into precision motor behaviors, and that functional connectivity of cerebellar-cortical sensorimotor and nonsensorimotor networks show delayed maturation.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Encéfalo/fisiopatologia , Conectoma , Rede Nervosa/fisiopatologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Adulto Jovem
19.
Schizophr Bull ; 48(1): 251-261, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-34337670

RESUMO

BACKGROUND: Thalamocortical circuit imbalance characterized by prefronto-thalamic hypoconnectivity and sensorimotor-thalamic hyperconnectivity has been consistently documented at rest in schizophrenia (SCZ). However, this thalamocortical imbalance has not been studied during task engagement to date, limiting our understanding of its role in cognitive dysfunction in schizophrenia. METHODS: Both n-back working memory (WM) task-fMRI and resting-state fMRI data were collected from 172 patients with SCZ and 103 healthy control subjects (HC). A replication sample with 49 SCZ and 48 HC was independently obtained. Sixteen thalamic subdivisions were employed as seeds for the analysis. RESULTS: During both task-performance and rest, SCZ showed thalamic hyperconnectivity with sensorimotor cortices, but hypoconnectivity with prefrontal-cerebellar regions relative to controls. Higher sensorimotor-thalamic connectivity and lower prefronto-thalamic connectivity both relate to poorer WM performance (lower task accuracy and longer response time) and difficulties in discriminating target from nontarget (lower d' score) in n-back task. The prefronto-thalamic hypoconnectivity and sensorimotor-thalamic hyperconnectivity were anti-correlated both in SCZ and HCs; this anti-correlation was more pronounced with less cognitive demand (rest>0-back>2-back). These findings replicated well in the second sample. Finally, the hypo- and hyper-connectivity patterns during resting-state positively correlated with the hypo- and hyper-connectivity during 2-back task-state in SCZ respectively. CONCLUSIONS: The thalamocortical imbalance reflected by prefronto-thalamic hypoconnectivity and sensorimotor-thalamic hyperconnectivity is present both at rest and during task engagement in SCZ and relates to working memory performance. The frontal reduction, sensorimotor enhancement pattern of thalamocortical imbalance is a state-invariant feature of SCZ that affects a core cognitive function.


Assuntos
Disfunção Cognitiva/fisiopatologia , Conectoma , Transtornos da Memória/fisiopatologia , Memória de Curto Prazo/fisiologia , Rede Nervosa/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/fisiopatologia , Córtex Sensório-Motor/fisiopatologia , Tálamo/fisiopatologia , Adulto , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Feminino , Humanos , Masculino , Transtornos da Memória/diagnóstico por imagem , Transtornos da Memória/etiologia , Rede Nervosa/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Esquizofrenia/complicações , Esquizofrenia/diagnóstico por imagem , Córtex Sensório-Motor/diagnóstico por imagem , Tálamo/diagnóstico por imagem
20.
Artigo em Inglês | MEDLINE | ID: mdl-34389436

RESUMO

BACKGROUND: The latest studies have considered the time-dependent structures in dynamic brain networks. However, the effect of periphery structures on the temporal flow of information remains unexplored in patients with major depressive disorder (MDD). In this work, we aimed to explore the pattern of interactions between brain regions in MDD across space and time. METHODS: We concentrated on the temporal reachability of nodes in temporal brain networks derived from the resting-state functional magnetic resonance imaging (rs-fMRI) of 55 MDD patients and 62 sex-, age-matched healthy controls. Specifically, temporal connectedness and temporal efficiency (TEF) were estimated based on the length of temporal paths between node pairs. Subsequently, the temporal clustering coefficient (TCC) and temporal distance were jointly employed to explore the patterns in which a node's periphery structure affects its reachability. RESULTS: Significantly higher TEF and lower TCC were found in temporal brain networks in MDD. Besides, significant between-group differences of nodal TCC were detected in regions of sensory perception systems. Considering the temporal paths that begin or end at these regions, MDD patients showed several altered temporal distances. CONCLUSION: Our results showed that the temporal reachability of specific brain regions in MDD could be affected as their periphery structures evolve, which may explain the dysfunction of sensory perception systems in the spatiotemporal domain.


Assuntos
Encéfalo/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Rede Nervosa/fisiopatologia , Percepção , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Fatores de Tempo
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