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1.
Neuroscience ; 542: 59-68, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38369007

RESUMO

Brain Computer Interface (BCI) is a highly promising human-computer interaction method that can utilize brain signals to control external devices. BCI based on functional near-infrared spectroscopy (fNIRS) is considered a relatively new and promising paradigm. fNIRS is a technique of measuring functional changes in cerebral hemodynamics. It detects changes in the hemodynamic activity of the cerebral cortex by measuring oxyhemoglobin and deoxyhemoglobin (HbR) concentrations and inversely predicts the neural activity of the brain. At the present time, Deep learning (DL) methods have not been widely used in fNIRS decoding, and there are fewer studies considering both spatial and temporal dimensions for fNIRS classification. To solve these problems, we proposed an end-to-end hybrid neural network for feature extraction of fNIRS. The method utilizes a spatial-temporal convolutional layer for automatic extraction of temporally valid information and uses a spatial attention mechanism to extract spatially localized information. A temporal convolutional network (TCN) is used to further utilize the temporal information of fNIRS before the fully connected layer. We validated our approach on a publicly available dataset including 29 subjects, including left-hand and right-hand motor imagery (MI), mental arithmetic (MA), and a baseline task. The results show that the method has few training parameters and high accuracy, providing a meaningful reference for BCI development.


Assuntos
Interfaces Cérebro-Computador , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Redes Neurais de Computação , Algoritmos , Córtex Cerebral/diagnóstico por imagem , Mãos , Eletroencefalografia/métodos , Imaginação
2.
Neuroimage ; 285: 120453, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37979895

RESUMO

For information from sensory organs to be processed by the brain, it is usually passed to appropriate areas of the cerebral cortex. Almost all of this information passes through the thalamus, a relay structure that reciprocally connects to the vast majority of the cortex. The thalamus facilitates this information transfer through a set of thalamocortical connections that vary in cellular structure, molecular profiles, innervation patterns, and firing rates. Additionally, corticothalamic connections allow for intracortical information transfer through the thalamus. These efferent and afferent connections between the thalamus and cortex have been the focus of many studies, and the importance of cortical connectivity in defining thalamus anatomy is demonstrated by multiple studies that parcellate the thalamus based on cortical connectivity profiles. Here, we examine correlated morphological variation between the thalamus and cortex, or thalamocortical structural covariance. For each voxel in the thalamus as a seed, we construct a cortical structural covariance map that represents correlated cortical volume variation, and examine whether high structural covariance is observed in cortical areas that are functionally relevant to the seed. Then, using these cortical structural covariance maps as features, we subdivide the thalamus into six non-overlapping regions (clusters of voxels), and assess whether cortical structural covariance is associated with cortical connectivity that specifically originates from these regions. We show that cortical structural covariance is high in areas of the cortex that are functionally related to the seed voxel, cortical structural covariance varies along cortical depth, and sharp transitions in cortical structural covariance profiles are observed when varying seed locations in the thalamus. Subdividing the thalamus based on structural covariance, we additionally demonstrate that the six thalamic clusters of voxels stratify cortical structural covariance along the dorsal-ventral, medial-lateral, and anterior-posterior axes. These cluster-associated structural covariance patterns are prominently detected in cortical regions innervated by fibers projecting out of their related thalamic subdivisions. Together, these results advance our understanding of how the thalamus and the cortex couple in their volumes. Our results indicate that these volume correlations reflect functional organization and structural connectivity, and further provides a novel segmentation of the mouse thalamus that can be used to examine thalamic structural variation and thalamocortical structural covariation in disease models.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Camundongos , Animais , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Vias Neurais , Encéfalo , Tálamo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem
3.
Brain Res Bull ; 205: 110837, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38043647

RESUMO

Neuroimaging research has revealed significant changes in brain structure and function in patients with cervical spondylotic myelopathy(CSM). The thalamus plays a crucial role in this process, although its mechanisms of action remain incompletely understood. This study aimed to investigate whether spinal cord compression leads to alterations in the functional connectivity between the thalamus and the cerebral cortex, and to determine if such changes are associated with structural and functional remodeling of the brain in patients with CSM, and to identify potential neuroimaging biomarkers for classification. The study included 40 patients with CSM and 34 healthy controls(HCs) who underwent resting-state functional magnetic resonance imaging(fMRI) and structural MRI scans. Brain structural and functional metrics were quantified using functional connectivity(FC), fractional amplitude of low-frequency fluctuations(fALFF), surface-based morphometry(SBM), and independent component analysis(ICA) based on functional and structural MRI. Patients with CSM exhibited significantly reduced fALFF in the bilateral lateral lingual gyrus, bilateral calcarine fissure, left precentral gyrus and postcentral gyrus, left middle and superior occipital gyrus, left superior marginal gyrus, left inferior parietal gyrus, and right Rolandic operculum. ICA results revealed weakened functional connectivity between the sensorimotor network (SMN) and the left and right frontoparietal network(FPN), and lateral visual network (lVN), along with decreased connectivity between lVN and rFPN, and increased connectivity between lFPN and rFPN. Patients with CSM also had decreased sulcus depth in the bilateral insula, left precentral and postcentral gyrus, and right lingual gyrus and calcarine fissure. Furthermore, cervical spondylotic myelopathy patients showed decreased functional connectivity between the left ventral posterolateral nucleus (VPL) of the thalamus and the right middle occipital gyrus (MOG). Finally,multimodal neuroimaging with support vector machine(SVM) classified patients with CSM and healthy controls with 86.00% accuracy. Our study revealed that the decrease in functional connectivity between the thalamus and cortex mediated by spinal cord compression leads to structural and functional reorganization of the cortex. Features based on neuroimaging markers have the potential to become neuroimaging biomarkers for CSM.


Assuntos
Compressão da Medula Espinal , Doenças da Medula Espinal , Humanos , Córtex Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tálamo/diagnóstico por imagem , Biomarcadores
4.
Brain Behav ; 13(12): e3296, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37904336

RESUMO

Extensive research has demonstrated the critical role of selenium (Se) and selenoproteins in brain function and cognition. However, the impact of Se on brain cortical structure remains enigmatic. Therefore, this study used Mendelian randomization (MR) analysis to investigate the causal effect between Se levels and brain cortical structure. METHODS: This study utilizes 11 genetic variants associated with Se level variations, extracted from a large-scale genome-wide association study (GWAS) encompassed circulating Se levels (n = 5477) and toenail Se levels (n = 4162) in the European population. Outcome data were sourced from the summary statistics of the ENIGMA Consortium, comprising GWAS data from 51,666 individuals. The variables include cortical surface area (SA), thickness (TH) at the global level, and 34 functional cortical regions evaluated by magnetic resonance imaging. The inverse-variance-weighted method was used as the primary estimate. Additionally, sensitivity analyses were conducted to detect potential violations of assumptions underlying MR. RESULTS: At the global level, Se levels were not correlated with SA but showed a significant negative correlation with TH (ß = -0.00485 mm, SE = 0.00192, p = .0115). Heterogeneity was observed across different brain regions, with positive correlations found between Se levels and the TH of the parahippocampal gyrus, superior frontal gyrus, and frontal pole, whereas negative correlations were found with the TH of the inferior parietal lobe and middle temporal lobe. Regarding SA, Se levels exhibit positive correlations with the pars triangularis, caudal anterior cingulate, inferior parietal lobe, and banks of the superior temporal sulcus. Conversely, negative correlations were observed with the medial orbitofrontal cortex, posterior cingulate gyrus, insula, and the middle, superior, and transverse gyrus of the temporal lobe. No pleiotropy was detected. RESULTS: This MR study indicated that Se levels causally influence the brain cortical structure.


Assuntos
Selênio , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia
5.
Neuroimage ; 283: 120414, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37858906

RESUMO

The role of the thalamus in mediating the effects of lysergic acid diethylamide (LSD) was recently proposed in a model of communication and corroborated by imaging studies. However, a detailed analysis of LSD effects on nuclei-resolved thalamocortical connectivity is still missing. Here, in a group of healthy volunteers, we evaluated whether LSD intake alters the thalamocortical coupling in a nucleus-specific manner. Structural and resting-state functional Magnetic Resonance Imaging (MRI) data were acquired in a placebo-controlled study on subjects exposed to acute LSD administration. Structural MRI was used to parcel the thalamus into its constituent nuclei based on individual anatomy. Nucleus-specific changes of resting-state functional MRI (rs-fMRI) connectivity were mapped using a seed-based approach. LSD intake selectively increased the thalamocortical functional connectivity (FC) of the ventral complex, pulvinar, and non-specific nuclei. Functional coupling was increased between these nuclei and sensory cortices that include the somatosensory and auditory networks. The ventral and pulvinar nuclei also exhibited increased FC with parts of the associative cortex that are dense in serotonin type 2A receptors. These areas are hyperactive and hyper-connected upon LSD intake. At subcortical levels, LSD increased the functional coupling among the thalamus's ventral, pulvinar, and non-specific nuclei, but decreased the striatal-thalamic connectivity. These findings unravel some LSD effects on the modulation of subcortical-cortical circuits and associated behavioral outputs.


Assuntos
Pulvinar , Tálamo , Humanos , Tálamo/fisiologia , Imageamento por Ressonância Magnética , Córtex Cerebral/diagnóstico por imagem , Lobo Parietal , Vias Neurais
6.
Hum Brain Mapp ; 44(15): 5153-5166, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37605827

RESUMO

BACKGROUND: Spatial patterns of brain functional connectivity can vary substantially at the individual level. Applying cortical surface-based approaches with individualized rather than group templates may accelerate the discovery of biological markers related to psychiatric disorders. We investigated cortico-subcortical networks from multi-cohort data in people with schizophrenia spectrum disorders (SSDs) and healthy controls (HC) using individualized connectivity profiles. METHODS: We utilized resting-state and anatomical MRI data from n = 406 participants (n = 203 SSD, n = 203 HC) from four cohorts. Functional timeseries were extracted from previously defined intrinsic network subregions of the striatum, thalamus, and cerebellum as well as 80 cortical regions of interest, representing six intrinsic networks using (1) volume-based approaches, (2) a surface-based group atlas approaches, and (3) Personalized Intrinsic Network Topography (PINT). RESULTS: The correlations between all cortical networks and the expected subregions of the striatum, cerebellum, and thalamus were increased using a surface-based approach (Cohen's D volume vs. surface 0.27-1.00, all p < 10-6 ) and further increased after PINT (Cohen's D surface vs. PINT 0.18-0.96, all p < 10-4 ). In SSD versus HC comparisons, we observed robust patterns of dysconnectivity that were strengthened using a surface-based approach and PINT (Number of differing pairwise-correlations: volume: 404, surface: 570, PINT: 628, FDR corrected). CONCLUSION: Surface-based and individualized approaches can more sensitively delineate cortical network dysconnectivity differences in people with SSDs. These robust patterns of dysconnectivity were visibly organized in accordance with the cortical hierarchy, as predicted by computational models.


Assuntos
Córtex Cerebral , Neuroimagem Funcional , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Masculino , Feminino , Adulto , Córtex Cerebral/diagnóstico por imagem , Adolescente , Adulto Jovem , Imageamento por Ressonância Magnética , Descanso , Corpo Estriado/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Cerebelo/diagnóstico por imagem
7.
Schizophr Bull ; 49(5): 1375-1386, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37078906

RESUMO

BACKGROUND AND HYPOTHESIS: Schizophrenia is a polygenetic mental disorder with heterogeneous positive and negative symptom constellations, and is associated with abnormal cortical connectivity. The thalamus has a coordinative role in cortical function and is key to the development of the cerebral cortex. Conversely, altered functional organization of the thalamus might relate to overarching cortical disruptions in schizophrenia, anchored in development. STUDY DESIGN: Here, we contrasted resting-state fMRI in 86 antipsychotic-naive first-episode early-onset schizophrenia (EOS) patients and 91 typically developing controls to study whether macroscale thalamic organization is altered in EOS. Employing dimensional reduction techniques on thalamocortical functional connectome (FC), we derived lateral-medial and anterior-posterior thalamic functional axes. STUDY RESULTS: We observed increased segregation of macroscale thalamic functional organization in EOS patients, which was related to altered thalamocortical interactions both in unimodal and transmodal networks. Using an ex vivo approximation of core-matrix cell distribution, we found that core cells particularly underlie the macroscale abnormalities in EOS patients. Moreover, the disruptions were associated with schizophrenia-related gene expression maps. Behavioral and disorder decoding analyses indicated that the macroscale hierarchy disturbances might perturb both perceptual and abstract cognitive functions and contribute to negative syndromes in patients. CONCLUSIONS: These findings provide mechanistic evidence for disrupted thalamocortical system in schizophrenia, suggesting a unitary pathophysiological framework.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tálamo/diagnóstico por imagem , Vias Neurais
8.
Brain Behav ; 13(2): e2894, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36692975

RESUMO

BACKGROUND AND PURPOSE: The autonomous sensory meridian response (ASMR) is a multimodal perceptual phenomenon in which specific sensory triggers evoke tingling sensations on the scalp, neck, and shoulders; these sensations are accompanied by a positive and calming affective state. Previous functional neuroimaging research has shown that ASMR experiences involve medial prefrontal and sensorimotor brain areas. The purpose of the current study was to examine whether there are structural differences in the cortex of individuals who experience ASMR. METHODS: Seventeen individuals with ASMR and 17 matched control participants completed an MPRAGE structural MRI scan. These data were analyzed to determine if group differences were present for measures of cortical thickness, cortical complexity, sulcal depth, and gyrification. RESULTS: ASMR was associated with reduced cortical thickness in a number of regions including the left precuneus, precentral gyrus, and insula, and the right orbitofrontal cortex, superior frontal cortex, and paracentral lobule. Reduced thickness was observed bilaterally in the supramarginal gyrus. Individuals with ASMR also showed less cortical complexity in the pars opercularis and pars triangularis. CONCLUSIONS: The differences in cortical thickness and complexity were in brain areas whose functions relate to the ASMR experience. These differences include neural regions related to phonological processing, sensorimotor functions, and attention.


Assuntos
Meridianos , Córtex Motor , Humanos , Encéfalo , Emoções , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Córtex Cerebral/diagnóstico por imagem
9.
Autism Res ; 16(2): 271-279, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36546577

RESUMO

There is converging evidence that abnormal thalamocortical interactions contribute to attention deficits and sensory sensitivities in autism spectrum disorder (ASD). However, previous functional MRI studies of thalamocortical connectivity in ASD have produced inconsistent findings in terms of both the direction (hyper vs. hypoconnectivity) and location of group differences. This may reflect, in part, the confounding effects of head motion during scans. In the present study, we investigated resting-state thalamocortical functional connectivity in 8-25 year-olds with ASD and their typically developing (TD) peers. We used pre-scan training, on-line motion correction, and rigorous data quality assurance protocols to minimize motion confounds. ASD participants showed increased thalamic connectivity with temporal cortex relative to TD. Both groups showed similar age-related decreases in thalamic connectivity with occipital cortex, consistent with a process of circuit refinement. Findings of thalamocortical hyperconnectivity in ASD are consistent with other evidence that decreased thalamic inhibition leads to increase and less filtered sensory information reaching the cortex where it disrupts attention and contributes to sensory sensitivity. This literature motivates studies of mechanisms, functional consequences, and treatment of thalamocortical circuit dysfunction in ASD.


Assuntos
Transtorno do Espectro Autista , Humanos , Criança , Adulto Jovem , Transtorno do Espectro Autista/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Lobo Occipital , Vias Neurais/diagnóstico por imagem , Mapeamento Encefálico/métodos
10.
J Neurophysiol ; 129(1): 17-40, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36197013

RESUMO

Multiple large-scale networks populate human association cortex. Here, we explored the functional properties of these networks by exploiting trial-to-trial variation in component-processing demands. In two behavioral studies (n = 136 and n = 238), participants quantified strategies used to solve individual task trials that spanned remembering, imagining future scenarios, and various control trials. These trials were also all scanned in an independent sample of functional MRI participants (n = 10), each with sufficient data to precisely define within-individual networks. Stable latent factors varied across trials and correlated with trial-level functional responses selectively across networks. One network linked to parahippocampal cortex, labeled Default Network A (DN-A), tracked scene construction, including for control trials that possessed minimal episodic memory demands. To the degree, a trial encouraged participants to construct a mental scene with imagery and awareness about spatial locations of objects or places, the response in DN-A increased. The juxtaposed Default Network B (DN-B) showed no such response but varied in relation to social processing demands. Another adjacent network, labeled Frontoparietal Network B (FPN-B), robustly correlated with trial difficulty. These results support that DN-A and DN-B are specialized networks differentially supporting information processing within spatial and social domains. Both networks are dissociable from a closely juxtaposed domain-general control network that tracks cognitive effort.NEW & NOTEWORTHY Tasks shown to differentially recruit parallel association networks are multifaceted, leaving open questions about network processes. Here, examining trial-to-trial network response properties in relation to trial traits reveals new insights into network functions. In particular, processes linked to scene construction selectively recruit a distributed network with links to parahippocampal and retrosplenial cortices, including during trials designed not to rely on the personal past. Adjacent networks show distinct patterns, providing novel evidence of functional specialization.


Assuntos
Córtex Cerebral , Memória Episódica , Humanos , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Cognição , Rememoração Mental/fisiologia , Giro do Cíngulo , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico
11.
Neuroimage Clin ; 35: 103102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35777251

RESUMO

Rolandic epilepsy (RE) is the most common focal, idiopathic, developmental epilepsy, characterized by a transient period of sleep-potentiated seizures and epileptiform discharges in the inferior Rolandic cortex during childhood. The cause of RE remains unknown but converging evidence has identified abnormalities in the Rolandic thalamocortical circuit. To better localize this transient disease, we evaluated Rolandic thalamocortical functional and structural connectivity in the sensory and motor circuits separately during the symptomatic and asymptomatic phases of this disease. We collected high resolution structural, diffusion, and resting state functional MRI data in a prospective cohort of children with active RE (n = 17), resolved RE (n = 21), and controls (n = 33). We then computed the functional and structural connectivity between the inferior Rolandic cortex and the ventrolateral (VL) nucleus of the thalamus (efferent pathway) and the ventroposterolateral (VPL) nucleus of the thalamus (afferent pathway) across development in children with active, resolved RE and controls. We compared connectivity with age in each group using linear mixed-effects models. We found that children with active RE have increasing thalamocortical functional connectivity between the VL thalamus and inferior motor cortex with age (p = 0.022) that is not observed in controls or resolved RE. In contrast, children with resolved RE have increasing thalamocortical structural connectivity between the VL nucleus and the inferior motor cortex with age (p = 0.025) that is not observed in controls or active RE. No relationships were identified between VPL nuclei and the inferior sensory cortex with age in any group. These findings localize the functional and structural thalamocortical circuit disruption in RE to the efferent thalamocortical motor pathway. Further work is required to determine how these circuit abnormalities contribute to the emergence and resolution of symptoms in this developmental disease.


Assuntos
Epilepsia Rolândica , Córtex Cerebral/diagnóstico por imagem , Criança , Epilepsia Rolândica/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Estudos Prospectivos , Tálamo/diagnóstico por imagem
12.
Neuroimage ; 255: 119175, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35390460

RESUMO

OBJECTIVE: Gamma synchrony is a fundamental functional property of the cerebral cortex, impaired in multiple neuropsychiatric conditions (i.e. schizophrenia, Alzheimer's disease, stroke etc.). Auditory stimulation in the gamma range allows to drive gamma synchrony of the entire cortical mantle and to estimate the efficiency of the mechanisms sustaining it. As gamma synchrony depends strongly on the interplay between parvalbumin-positive interneurons and pyramidal neurons, we hypothesize an association between cortical thickness and gamma synchrony. To test this hypothesis, we employed a combined magnetoencephalography (MEG) - Magnetic Resonance Imaging (MRI) study. METHODS: Cortical thickness was estimated from anatomical MRI scans. MEG measurements related to exposure of 40 Hz amplitude modulated tones were projected onto the cortical surface. Two measures of cortical synchrony were considered: (a) inter-trial phase consistency at 40 Hz, providing a vertex-wise estimation of gamma synchronization, and (b) phase-locking values between primary auditory cortices and whole cortical mantle, providing a measure of long-range cortical synchrony. A correlation between cortical thickness and synchronization measures was then calculated for 72 MRI-MEG scans. RESULTS: Both inter-trial phase consistency and phase locking values showed a significant positive correlation with cortical thickness. For inter-trial phase consistency, clusters of strong associations were found in the temporal and frontal lobes, especially in the bilateral auditory and pre-motor cortices. Higher phase-locking values corresponded to higher cortical thickness in the frontal, temporal, occipital and parietal lobes. DISCUSSION AND CONCLUSIONS: In healthy subjects, a thicker cortex corresponds to higher gamma synchrony and connectivity in the primary auditory cortex and beyond, likely reflecting underlying cell density involved in gamma circuitries. This result hints towards an involvement of gamma synchrony together with underlying brain structure in brain areas for higher order cognitive functions. This study contributes to the understanding of inherent cortical functional and structural brain properties, which might in turn constitute the basis for the definition of useful biomarkers in patients showing aberrant gamma synchronization.


Assuntos
Córtex Auditivo , Esquizofrenia , Estimulação Acústica/métodos , Córtex Auditivo/fisiologia , Córtex Cerebral/diagnóstico por imagem , Potenciais Evocados Auditivos/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Magnetoencefalografia/métodos
13.
Neurosci Lett ; 772: 136484, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35108589

RESUMO

Occupational burnout has become a pervasive problem, especially among medical professionals who are highly vulnerable to burnout. Since the beginning of the COVID-19 pandemic, medical professionals have faced greater levels of stress. It is critical to increase our understanding of the neurobiological mechanisms of burnout among medical professionals for the benefit of healthcare systems. Therefore, in this study, we investigated structural brain correlates of burnout severity in medical professionals using a voxel-based morphometric technique. Nurses in active service underwent structural magnetic resonance imaging. Two core dimensions of burnout, namely, emotional exhaustion and depersonalization, were assessed using self-reported psychological questionnaires. Levels of emotional exhaustion were found to be negatively correlated with gray matter (GM) volumes in the bilateral ventromedial prefrontal cortex (vmPFC) and left insula. Moreover, levels of depersonalization were negatively correlated with GM volumes in the left vmPFC and left thalamus. Altogether, these findings contribute to a better understanding of the neural mechanisms of burnout and may provide helpful insights for developing effective interventions for medical professionals.


Assuntos
Encéfalo/diagnóstico por imagem , Esgotamento Profissional/diagnóstico por imagem , Adulto , COVID-19 , Córtex Cerebral/diagnóstico por imagem , Despersonalização , Emoções , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Enfermeiras e Enfermeiros , Pandemias , Córtex Pré-Frontal/diagnóstico por imagem , Autorrelato , Inquéritos e Questionários , Tálamo/diagnóstico por imagem , Adulto Jovem
14.
Neuroimage Clin ; 33: 102953, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35139478

RESUMO

OBJECTIVE: The integration of somatosensory, ocular motor and vestibular signals is necessary for self-location in space and goal-directed action. We aimed to detect remote changes in the cerebral cortex after thalamic infarcts to reveal the thalamo-cortical connections necessary for multisensory processing and ocular motor control. METHODS: Thirteen patients with unilateral ischemic thalamic infarcts presenting with vestibular, somatosensory, and ocular motor symptoms were examined longitudinally in the acute phase and after six months. Voxel- and surface-based morphometry were used to detect changes in vestibular and multisensory cortical areas and known hubs of central ocular motor processing. The results were compared with functional connectivity data in 50 healthy volunteers. RESULTS: Patients with paramedian infarcts showed impaired saccades and vestibular perception, i.e., tilts of the subjective visual vertical (SVV). The most common complaint in these patients was double vision or vertigo / dizziness. Posterolateral thalamic infarcts led to tilts of the SVV and somatosensory deficits without vertigo. Tilts of the SVV were higher in paramedian compared to posterolateral infarcts (median 11.2° vs 3.8°). Vestibular and ocular motor symptoms recovered within six months. Somatosensory deficits persisted. Structural longitudinal imaging showed significant volume reduction in subcortical structures connected to the infarcted thalamic nuclei (vestibular nuclei region, dentate nucleus region, trigeminal root entry zone, medial lemniscus, superior colliculi). Volume loss was evident in connections to the frontal, parietal and cingulate lobes. Changes were larger in the ipsilesional hemisphere but were also detected in homotopical regions contralesionally. The white matter volume reduction led to deformation of the cortical projection zones of the infarcted nuclei. CONCLUSIONS: White matter volume loss after thalamic infarcts reflects sensory input from the brainstem as well the cortical projections of the main affected nuclei for sensory and ocular motor processing. Changes in the cortical geometry seem not to reflect gray matter atrophy but rather reshaping of the cortical surface due to the underlying white matter atrophy.


Assuntos
Vestíbulo do Labirinto , Substância Branca , Córtex Cerebral/diagnóstico por imagem , Infarto Cerebral/complicações , Infarto Cerebral/diagnóstico por imagem , Humanos , Tálamo/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
15.
Med Image Anal ; 77: 102316, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34979433

RESUMO

Increasing evidence suggests that cortical folding patterns of human cerebral cortex manifest overt structural and functional differences. However, for interpretability, few studies leverage advanced techniques (e.g., deep learning) to investigate the difference among cortical folds, resulting in more differences yet to be extensively explored. To this end, we proposed an effective topology-preserving transfer learning framework to differentiate cortical fMRI time series extracted from cortical folds. Our framework consists of three main parts: (1) Neural architecture search (NAS), which is used to devise a well-performing network structure based on an initialized hand-designed super-graph in an image dataset; (2) Topology-preserving transfer, which takes the model searched by NAS as the source network, keeping the topological connectivity in the network unchanged, while transforming all 2D operations including convolution and pooling into 1D, therefore resulting in a topology-preserving network, named TPNAS-Net; (3) Classification and correlation analysis, which involves using the TPNAS-Net to classify 1D cortical fMRI time series for each individual brain, and performing a group difference analysis between autism spectrum disorder (ASD) and healthy control (HC) and correlation analysis with clinical information (i.e., age). Extensive experiments on two ASD datasets obtain consistent results, demonstrating that the TPNAS-Net not only discriminates cortical folding patterns at high classification accuracy, but also captures subtle differences between ASD and HC (p-value = 0.042). In addition, we discover that there is a positive correlation between the classification accuracy and age in ASD (r = 0.39, p-value = 0.04). These findings together suggest that structural and functional differences in cortical folding patterns between ASD and HC may provide a potentially useful biomarker for the diagnosis of ASD.


Assuntos
Transtorno do Espectro Autista , Encéfalo , Córtex Cerebral/diagnóstico por imagem , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Extratos Vegetais
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.
Hum Brain Mapp ; 43(2): 647-664, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34738276

RESUMO

Music is known to induce emotions and activate associated memories, including musical memories. In adults, it is well known that music activates both working memory and limbic networks. We have recently discovered that as early as during the newborn period, familiar music is processed differently from unfamiliar music. The present study evaluates music listening effects at the brain level in newborns, by exploring the impact of familiar or first-time music listening on the subsequent resting-state functional connectivity in the brain. Using a connectome-based framework, we describe resting-state functional connectivity (RS-FC) modulation after music listening in three groups of newborn infants, in preterm infants exposed to music during their neonatal-intensive-care-unit (NICU) stay, in control preterm, and full-term infants. We observed modulation of the RS-FC between brain regions known to be implicated in music and emotions processing, immediately following music listening in all newborn infants. In the music exposed group, we found increased RS-FC between brain regions known to be implicated in familiar and emotionally arousing music and multisensory processing, and therefore implying memory retrieval and associative memory. We demonstrate a positive correlation between the occurrence of the prior music exposure and increased RS-FC in brain regions implicated in multisensory and emotional processing, indicating strong engagement of musical memories; and a negative correlation with the Default Mode Network, indicating disengagement due to the aforementioned cognitive processing. Our results describe the modulatory effect of music listening on brain RS-FC that can be linked to brain correlates of musical memory engrams in preterm infants.


Assuntos
Tonsila do Cerebelo/fisiologia , Percepção Auditiva/fisiologia , Córtex Cerebral/fisiologia , Conectoma , Rede de Modo Padrão/fisiologia , Emoções/fisiologia , Recém-Nascido Prematuro/fisiologia , Música , Reconhecimento Psicológico/fisiologia , Tálamo/fisiologia , Tonsila do Cerebelo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Rede de Modo Padrão/diagnóstico por imagem , Feminino , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Tálamo/diagnóstico por imagem
18.
Brain Res ; 1775: 147739, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34843702

RESUMO

Selective listening to speech depends on widespread networks of the brain, but how the involvement of different neural systems in speech processing is affected by factors such as the task performed by a listener and speech intelligibility remains poorly understood. We used functional magnetic resonance imaging to systematically examine the effects that performing different tasks has on neural activations during selective attention to continuous audiovisual speech in the presence of task-irrelevant speech. Participants viewed audiovisual dialogues and attended either to the semantic or the phonological content of speech, or ignored speech altogether and performed a visual control task. The tasks were factorially combined with good and poor auditory and visual speech qualities. Selective attention to speech engaged superior temporal regions and the left inferior frontal gyrus regardless of the task. Frontoparietal regions implicated in selective auditory attention to simple sounds (e.g., tones, syllables) were not engaged by the semantic task, suggesting that this network may not be not as crucial when attending to continuous speech. The medial orbitofrontal cortex, implicated in social cognition, was most activated by the semantic task. Activity levels during the phonological task in the left prefrontal, premotor, and secondary somatosensory regions had a distinct temporal profile as well as the highest overall activity, possibly relating to the role of the dorsal speech processing stream in sub-lexical processing. Our results demonstrate that the task type influences neural activations during selective attention to speech, and emphasize the importance of ecologically valid experimental designs.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Córtex Cerebral/diagnóstico por imagem , Percepção Visual/fisiologia , Estimulação Acústica , Adulto , Córtex Cerebral/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estimulação Luminosa , Adulto Jovem
19.
Hum Brain Mapp ; 43(3): 974-984, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34816523

RESUMO

Recent evidence suggests that presupplementary motor area (pre-SMA) and inferior frontal gyrus (IFG) play an important role in response inhibition. However, no study has investigated the relationship between these brain networks at resting-state and response inhibition in obsessive-compulsive disorder (OCD). We performed resting-state functional magnetic resonance imaging scans and then measured the response inhibition of 41 medication-free OCD patients and 49 healthy control (HC) participants by using the stop-signal task outside the scanner. We explored the differences between OCD and HC groups in the functional connectivity of pre-SMA and IFG associated with the ability of motor response inhibition. OCD patients showed a longer stop-signal reaction time (SSRT). Compared to HC, OCD patients exhibit different associations between the ability of motor response inhibition and the functional connectivity between pre-SMA and IFG, inferior parietal lobule, dorsal anterior cingulate cortex, insula, and anterior prefrontal cortex. Additional analysis to investigate the functional connectivity difference from the seed ROIs to the whole brain voxels revealed that, compared to HC, OCD exhibited greater functional connectivity between pre-SMA and IFG. Also, this functional connectivity was positively correlated with the SSRT score. These results provide additional insight into the characteristics of the resting-state functional connectivity of the regions belonging to the cortico-striato-thalamo-cortical circuit and the cingulo-opercular salience network, underlying the impaired motor response inhibition of OCD. In particular, we emphasize the importance of altered functional connectivity between pre-SMA and IFG for the pathophysiology of motor response inhibition in OCD.


Assuntos
Córtex Cerebral/fisiopatologia , Conectoma , Corpo Estriado/fisiopatologia , Inibição Psicológica , Atividade Motora/fisiologia , Córtex Motor/fisiopatologia , Rede Nervosa/fisiopatologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Tálamo/fisiopatologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Corpo Estriado/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Adulto Jovem
20.
Neuroimage ; 246: 118756, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34848297

RESUMO

The composite face effect (CFE) is recognized as a hallmark for holistic face processing, but our knowledge remains sparse about its cognitive and neural loci. Using functional magnetic resonance imaging with independent localizer and complete composite face task, we here investigated its neural-behavioral correspondence within face processing and attention networks. Complementing classical comparisons, we adopted a dimensional reduction approach to explore the core cognitive constructs of the behavioral CFE measurement. Our univariate analyses found an alignment effect in regions associated with both the extended face processing network and attention networks. Further representational similarity analyses based on Euclidian distances among all experimental conditions were used to identify cortical regions with reliable neural-behavioral correspondences. Multidimensional scaling and hierarchical clustering analyses for neural-behavioral correspondence data revealed two principal components underlying the behavioral CFE effect, which fit best to the neural responses in the bilateral insula and medial frontal gyrus. These findings highlight the distinct neurocognitive contributions of both face processing and attentional networks to the behavioral CFE outcome, which bridge the gaps between face recognition and attentional control models.


Assuntos
Atenção/fisiologia , Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Imagem Ecoplanar/métodos , Reconhecimento Facial/fisiologia , Rede Nervosa/fisiologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Adulto Jovem
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