Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.901
Filtrar
1.
Neurología (Barc., Ed. impr.) ; 38(4): 236-245, May. 2023. tab
Artigo em Espanhol | IBECS | ID: ibc-219232

RESUMO

Introducción: La eficacia de la trombectomía mecánica en territorio carotídeo en las primeras 24 horas se ha probado con trabajos publicados recientemente. Métodos: Revisión retrospectiva a partir de un registro prospectivo en nuestro centro de referencia de ictus para valorar la eficacia y seguridad del tratamiento endovascular realizado más allá de las 6 horas de evolución de los síntomas en pacientes con ictus isquémico agudo y oclusión de gran vaso en territorio carotídeo, entre noviembre de 2016 y abril de 2019. Resultados: Se recopilaron datos de 59 pacientes (55,9% mujeres, mediana de edad 71 años). Treinta y tres pacientes fueron detectados al despertar. El 57,6% de los casos fueron traslados secundarios. La mediana de NIHSS basal fue 16. La mediana del ASPECTS fue 8 y el 94,9% de los pacientes presentó > 50% de tejido salvable. El 88,1% de los pacientes logró una recanalización satisfactoria, en 5 pacientes después de 24 horas de evolución. El 67,8% de los casos logró la independencia funcional a los 90 días de seguimiento. Los pacientes que no lograron la independencia funcional presentaban mayor edad, mayor proporción de fibrilación auricular, mayor tiempo punción-recanalización y mayor puntuación NIHSS, tanto basal como al alta. Conclusión: En nuestra experiencia la trombectomía mecánica después de las 6 horas se asoció con buenos resultados de funcionalidad a los 90 días. La edad, la puntuación NIHSS, el tiempo punción-recanalización y la prevalencia de fibrilación auricular fueron factores determinantes en el pronóstico funcional. La eficacia de este tratamiento por encima de las 24 horas merece ser estudiada.(AU)


Introduction: Thrombectomy in the carotid artery territory was recently shown to be effective up to 24 hours after symptoms onset. Methods: We conducted a retrospective review of a prospective registry of patients treated at our stroke reference centre between November 2016 and April 2019 in order to assess the safety and effectiveness of mechanical thrombectomy performed beyond 6 hours after symptoms onset in patients with acute ischaemic stroke and large vessel occlusion in the carotid artery territory. Results: Data were gathered from 59 patients (55.9% women; median age, 71 years). In 33 cases, stroke was detected upon awakening; 57.6% of patients were transferred from another hospital. Median baseline NIHSS score was 16, and median ASPECTS score was 8, with 94.9% of patients presenting > 50% of salvageable tissue. Satisfactory recanalisation was achieved in 88.1% of patients, beyond 24 hours after onset in 5 cases. At 90 days of follow-up, 67.8% were functionally independent; those who were not were older and presented higher prevalence of atrial fibrillation, greater puncture-to-recanalisation time, and higher NIHSS scores, both at baseline and at discharge. Conclusion: In our experience, mechanical thrombectomy beyond 6 hours was associated with good 90-day functional outcomes. Age, NIHSS score, puncture-to-recanalisation time, and presence of atrial fibrillation affected functional prognosis. The efficacy of the treatment beyond 24 hours after onset merits study.(AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Acidente Vascular Cerebral , Trombectomia , Neuroimagem Funcional , Tomografia Computadorizada por Raios X , Imagem de Perfusão , Estudos Retrospectivos , Neurologia
2.
Neurosci Biobehav Rev ; 149: 105171, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37060968

RESUMO

The cerebellum generates internal prediction models and actively compares anticipated and actual outcomes in order to reach a desired end state. In this process, reward can serve as a reinforcer that shapes internal prediction models, enabling context-appropriate behavior. While the involvement of the cerebellum in reward processing has been established in animals, there is no detailed account of which cerebellar regions are involved in reward anticipation and outcome processing in humans. To this end, an activation likelihood estimation meta-analysis of functional neuroimaging studies was performed to investigate cerebellar functional activity patterns associated with reward anticipation and outcome processing in healthy adults. Results showed that reward anticipation (k = 31) was associated with regional activity in the bilateral anterior lobe, bilateral lobule VI, left Crus I and the posterior vermis, while reward outcome (k = 16) was associated with regional activity in the declive and left lobule VI. These findings demonstrate distinct involvement of the cerebellum in reward anticipation and outcome processing as part of a predictive coding routine.


Assuntos
Cerebelo , Imageamento por Ressonância Magnética , Adulto , Humanos , Funções Verossimilhança , Neuroimagem Funcional , Recompensa , Antecipação Psicológica/fisiologia
3.
Brain Topogr ; 36(3): 350-370, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37046041

RESUMO

Magnetoencephalography (MEG) is a noninvasive functional neuroimaging modality but highly susceptible to environmental interference. Signal space separation (SSS) is a method for improving the SNR to separate the MEG signals from external interference. The origin and truncation values of SSS significantly affect the SSS performance. The origin value fluctuates with respect to the helmet array, and determining the truncation values using the traversal method is time-consuming; thus, this method is inappropriate for optically pumped magnetometer (OPM) systems with flexible array designs. Herein, an automatic optimization method for the SSS parameters is proposed. Virtual sources are set inside and outside the brain to simulate the signals of interest and interference, respectively, via forward model, with the sensor array as prior information. The objective function is determined as the error between the signals from simulated sources inside the brain and the SSS reconstructed signals; thus, the optimized parameters are solved inversely by minimizing the objective function. To validate the proposed method, a simulation analysis and MEG auditory-evoked experiments were conducted. For an OPM sensor array, this method can precisely determine the optimized origin and truncation values of the SSS simultaneously, and the auditory-evoked component, for example, N100, can be accurately located in the temporal cortex. The proposed optimization procedure outperforms the traditional method with regard to the computation time and accuracy, simplifying the SSS process in signal preprocessing and enhancing the performance of SSS denoising.


Assuntos
Encéfalo , Magnetoencefalografia , Humanos , Magnetoencefalografia/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Simulação por Computador , Neuroimagem Funcional
4.
Int. j. clin. health psychol. (Internet) ; 23(2): 1-10, abr.-jun. 2023. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-213882

RESUMO

Objective: Functional neuroimaging may provide a viable means of assessment and communication in patients with Guillain-Barré Syndrome (GBS) mimicking the complete locked-in state. Functional neuroimaging has been used to assess residual cognitive function and has allowed for binary communication with other behaviourally non-responsive patients, such as those diagnosed with unresponsive wakefulness syndrome. We evaluated the potential application of functional neuroimaging using a clinical-grade scanner to determine if individuals with severe GBS retained auditory function, command following, and communication. Methods: Fourteen healthy participants and two GBS patients were asked to perform motor imagery and spatial navigation imagery tasks while being scanned using functional magnetic resonance imaging. The GBS patients were also asked to perform additional functional neuroimaging scans to attempt communication. Results: The motor imagery and spatial navigation task elicited significant activation in appropriate regions of interest for both GBS patients, indicating intact command following. Both patients were able to use the imagery technique to communicate in some instances. Patient 1 was able to use one of four communication tasks to answer a question correctly. Patient 2 was able to use three of seven communication tasks. However, two questions were incorrectly answered while a third was non-verifiable. Conclusions: GBS patients can respond using mental imagery and these responses can be detected using functional neuroimaging. Furthermore, these patients may also be able to use mental imagery to provide answers to ‘yes’ or ‘no’ questions in some instances. We argue that the most appropriate use of neuroimaging-based communication in these patients is to allow them to communicate wishes or preferences and assent to previously expressed decisions, rather than to facilitate decision-making. (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Idoso , Síndrome de Guillain-Barré , Cognição , Neuroimagem Funcional , Espectroscopia de Ressonância Magnética
5.
J Biomed Opt ; 28(3): 036002, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36908760

RESUMO

Significance: Imaging through scattering media is critical in many biomedical imaging applications, such as breast tumor detection and functional neuroimaging. Time-of-flight diffuse optical tomography (ToF-DOT) is one of the most promising methods for high-resolution imaging through scattering media. ToF-DOT and many traditional DOT methods require an image reconstruction algorithm. Unfortunately, this algorithm often requires long computational runtimes and may produce lower quality reconstructions in the presence of model mismatch or improper hyperparameter tuning. Aim: We used a data-driven unrolled network as our ToF-DOT inverse solver. The unrolled network is faster than traditional inverse solvers and achieves higher reconstruction quality by accounting for model mismatch. Approach: Our model "Unrolled-DOT" uses the learned iterative shrinkage thresholding algorithm. In addition, we incorporate a refinement U-Net and Visual Geometry Group (VGG) perceptual loss to further increase the reconstruction quality. We trained and tested our model on simulated and real-world data and benchmarked against physics-based and learning-based inverse solvers. Results: In experiments on real-world data, Unrolled-DOT outperformed learning-based algorithms and achieved over 10× reduction in runtime and mean-squared error, compared to traditional physics-based solvers. Conclusion: We demonstrated a learning-based ToF-DOT inverse solver that achieves state-of-the-art performance in speed and reconstruction quality, which can aid in future applications for noninvasive biomedical imaging.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Óptica , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Matemática , Tomografia Óptica/métodos , Neuroimagem Funcional
6.
J Affect Disord ; 331: 64-76, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36924847

RESUMO

BACKGROUND: Early evidence suggests that unexpected non-reward may increase the risk for aggressive behaviors. Despite the growing interest in understanding brain functions that may be implicated in aggressive behaviors, the neural processes underlying such frustrative events remain largely unknown. Furthermore, meta-analytic results have produced discrepant results, potentially due to substantial differences in the definition of anger/aggression constructs. METHODS: Therefore, we conducted a coordinate-based meta-analysis, using the activation likelihood estimation algorithm, on neuroimaging studies examining reward omission and retaliatory behaviors in healthy subjects. Conjunction analyses were further examined to discover overlapping brain activations across these meta-analytic maps. RESULTS: Frustrative non-reward deactivated the orbitofrontal cortex, ventral striatum and posterior cingulate cortex, whereas increased activations were observed in midcingulo-insular regions. Retaliatory behaviors recruited the left fronto-insular and anterior midcingulate cortices, the dorsal caudate and the primary somatosensory cortex. Conjunction analyses revealed that both strongly activated midcingulo-insular regions. LIMITATIONS: Spatial overlap between neural correlates of frustration and retaliatory behaviors was conducted using a conjunction analysis. Therefore, neurobiological markers underlying the temporal sequence of the frustration-aggression theory should be interpreted with caution. CONCLUSIONS: Nonetheless, our results underscore the role of anterior midcingulate/pre-supplementary motor area and fronto-insular cortex in both frustration and retaliatory behaviors. A neurobiological framework for understanding frustration-based impulsive aggression is provided.


Assuntos
Frustração , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo , Agressão/fisiologia , Neuroimagem Funcional , Neuroimagem , Mapeamento Encefálico/métodos
7.
Transl Psychiatry ; 13(1): 75, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864017

RESUMO

In recent years, machine learning (ML) has been a promising approach in the research of treatment outcome prediction in psychosis. In this study, we reviewed ML studies using different neuroimaging, neurophysiological, genetic, and clinical features to predict antipsychotic treatment outcomes in patients at different stages of schizophrenia. Literature available on PubMed until March 2022 was reviewed. Overall, 28 studies were included, among them 23 using a single-modality approach and 5 combining data from multiple modalities. The majority of included studies considered structural and functional neuroimaging biomarkers as predictive features used in ML models. Specifically, functional magnetic resonance imaging (fMRI) features contributed to antipsychotic treatment response prediction of psychosis with good accuracies. Additionally, several studies found that ML models based on clinical features might present adequate predictive ability. Importantly, by examining the additive effects of combining features, the predictive value might be improved by applying multimodal ML approaches. However, most of the included studies presented several limitations, such as small sample sizes and a lack of replication tests. Moreover, considerable clinical and analytical heterogeneity among included studies posed a challenge in synthesizing findings and generating robust overall conclusions. Despite the complexity and heterogeneity of methodology, prognostic features, clinical presentation, and treatment approaches, studies included in this review suggest that ML tools may have the potential to predict treatment outcomes of psychosis accurately. Future studies need to focus on refining feature characterization, validating prediction models, and evaluate their translation in real-world clinical practice.


Assuntos
Antipsicóticos , Transtornos Psicóticos , Humanos , Antipsicóticos/uso terapêutico , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/tratamento farmacológico , Neuroimagem Funcional , Aprendizado de Máquina , Neuroimagem
8.
Neurosci Biobehav Rev ; 147: 105109, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36813146

RESUMO

Impulsivity is a common feature of bipolar disorder (BD) with ramifications for functional impairment and premature mortality. This PRISMA-guided systematic review aims to integrate findings on the neurocircuitry associated with impulsivity in BD. We searched for functional neuroimaging studies that examined rapid-response impulsivity and choice impulsivity using the Go/No-Go Task, Stop-Signal Task, and Delay Discounting Task. Findings from 33 studies were synthesized with an emphasis on the effect of mood state of the sample and affective salience of the task. Results suggest trait-like brain activation abnormalities in regions implicated in impulsivity that persist across mood states. During rapid-response inhibition, BD exhibit under-activation of key frontal, insular, parietal, cingulate, and thalamic regions, but over-activation of these regions when the task involves emotional stimuli. Delay discounting tasks with functional neuroimaging in BD are lacking, but hyperactivity of orbitofrontal and striatal regions associated with reward hypersensitivity may be related to difficulty delaying gratification. We propose a working model of neurocircuitry dysfunction underlying behavioral impulsivity in BD. Clinical implications and future directions are discussed.


Assuntos
Transtorno Bipolar , Humanos , Comportamento Impulsivo/fisiologia , Emoções/fisiologia , Recompensa , Neuroimagem Funcional , Imageamento por Ressonância Magnética/métodos
9.
Commun Biol ; 6(1): 135, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725984

RESUMO

Perception is an active inference in which prior expectations are combined with sensory input. It is still unclear how the strength of prior expectations is represented in the human brain. The strength, or precision, of a prior could be represented with its content, potentially in higher-level sensory areas. We used multivariate analyses of functional resonance imaging data to test whether expectation strength is represented together with the expected face in high-level face-sensitive regions. Participants were trained to associate images of scenes with subsequently presented images of different faces. Each scene predicted three faces, each with either low, intermediate, or high probability. We found that anticipation enhances the similarity of response patterns in the face-sensitive anterior temporal lobe to response patterns specifically associated with the image of the expected face. In contrast, during face presentation, activity increased for unexpected faces in a typical prediction error network, containing areas such as the caudate and the insula. Our findings show that strength-dependent face expectations are represented in higher-level face-identity areas, supporting hierarchical theories of predictive processing according to which higher-level sensory regions represent weighted priors.


Assuntos
Mapeamento Encefálico , Motivação , Humanos , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Análise Multivariada , Neuroimagem Funcional
10.
Neuron ; 111(8): 1316-1330.e5, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-36803653

RESUMO

Hierarchical processing requires activity propagating between higher- and lower-order cortical areas. However, functional neuroimaging studies have chiefly quantified fluctuations within regions over time rather than propagations occurring over space. Here, we leverage advances in neuroimaging and computer vision to track cortical activity propagations in a large sample of youth (n = 388). We delineate cortical propagations that systematically ascend and descend a cortical hierarchy in all individuals in our developmental cohort, as well as in an independent dataset of densely sampled adults. Further, we demonstrate that top-down, descending hierarchical propagations become more prevalent with greater demands for cognitive control as well as with development in youth. These findings emphasize that hierarchical processing is reflected in the directionality of propagating cortical activity and suggest top-down propagations as a potential mechanism of neurocognitive maturation in youth.


Assuntos
Imageamento por Ressonância Magnética , Visão Ocular , Adulto , Humanos , Adolescente , Neuroimagem , Neuroimagem Funcional
11.
Neuroimage ; 270: 119949, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36804422

RESUMO

As the neuroimaging field moves towards detecting smaller effects at higher spatial resolutions, and faster sampling rates, there is increased attention given to the deleterious contribution of unstructured, thermal noise. Here, we critically evaluate the performance of a recently developed reconstruction method, termed NORDIC, for suppressing thermal noise using datasets acquired with various field strengths, voxel sizes, sampling rates, and task designs. Following minimal preprocessing, statistical activation (t-values) of NORDIC processed data was compared to the results obtained with alternative denoising methods. Additionally, we examined the consistency of the estimates of task responses at the single-voxel, single run level, using a finite impulse response (FIR) model. To examine the potential impact on effective image resolution, the overall smoothness of the data processed with different methods was estimated. Finally, to determine if NORDIC alters or removes temporal information important for modeling responses, we employed an exhaustive leave-p-out cross validation approach, using FIR task responses to predict held out timeseries, quantified using R2. After NORDIC, the t-values are increased, an improvement comparable to what could be achieved by 1.5 voxels smoothing, and task events are clearly visible and have less cross-run error. These advantages are achieved with smoothness estimates increasing by less than 4%, while 1.5 voxel smoothing is associated with increases of over 140%. Cross-validated R2s based on the FIR models show that NORDIC is not measurably distorting the temporal structure of the data under this approach and is the best predictor of non-denoised time courses. The results demonstrate that analyzing 1 run of data after NORDIC produces results equivalent to using 2 to 3 original runs and that NORDIC performs equally well across a diverse array of functional imaging protocols. Significance Statement: For functional neuroimaging, the increasing availability of higher field strengths and ever higher spatiotemporal resolutions has led to concomitant increase in concerns about the deleterious effects of thermal noise. Historically this noise source was suppressed using methods that reduce spatial precision such as image blurring or averaging over a large number of trials or sessions, which necessitates large data collection efforts. Here, we critically evaluate the performance of a recently developed reconstruction method, termed NORDIC, which suppresses thermal noise. Across datasets varying in field strength, voxel sizes, sampling rates, and task designs, NORDIC produces substantial gains in data quality. Both conventional t-statistics derived from general linear models and coefficients of determination for predicting unseen data are improved. These gains match or even exceed those associated with 1 voxel Full Width Half Max image smoothing, however, even such small amounts of smoothing are associated with a 52% reduction in estimates of spatial precision, whereas the measurable difference in spatial precision is less than 4% following NORDIC.


Assuntos
Neuroimagem Funcional , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Neuroimagem Funcional/métodos , Projetos de Pesquisa , Processamento de Imagem Assistida por Computador/métodos
12.
Trends Cogn Sci ; 27(5): 433-445, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36740518

RESUMO

Recent findings suggesting the potential transdiagnostic efficacy of psychedelic-assisted therapy have fostered the need to deepen our understanding of psychedelic brain action. Functional neuroimaging investigations have found that psychedelics reduce the functional segregation of large-scale brain networks. However, beyond this general trend, findings have been largely inconsistent. We argue here that a perspective based on complexity science that foregrounds the distributed, interactional, and dynamic nature of brain function may render these inconsistencies intelligible. We propose that psychedelics induce a mode of brain function that is more dynamically flexible, diverse, integrated, and tuned for information sharing, consistent with greater criticality. This 'meta' perspective has the potential to unify past findings and guide intuitions toward compelling mechanistic models.


Assuntos
Alucinógenos , Humanos , Alucinógenos/farmacologia , Encéfalo , Neuroimagem Funcional
13.
Cortex ; 160: 43-54, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36680923

RESUMO

Developmental dyslexia (DD) and developmental coordination disorder (DCD) are two common neurodevelopmental disorders with a high co-occurrence rate. This led several authors to postulate that the two disorders share, at least partially, similar neural underpinning. However, even though several studies examined brain differences between typically developing (TD) children and children with either DD or DCD, no previous study directly compared DD, DCD and children with both disorders (COM) using neuroimaging. We acquired structural and resting-state functional MRI images of 136 children (TD = 42, DD = 45, DCD = 20, COM = 29). Difference between TD children and the other groups was assessed using univariate analysis of structural indexes including grey and white matter volumes and functional indexes quantifying activity (fraction of the amplitude of the low frequency fluctuations), local and global connectivity. Regional differences in structural and functional brain indexes were then used to train machine learning models to discriminate among DD, DCD and COM and to find the most discriminant regions. While no imaging index alone discriminated between the three groups, grouping grey and white matter volumes (structural model) or activity, local and global connectivity (functional model) made possible to discriminate among the DD, DCD and COM groups. The most important discrimination was obtained using the functional model, with regions in the cerebellum and the temporal lobe being the most discriminant for DCD and DD children, respectively. Results further showed that children with both DD and DCD have subtle but identifiable brain differences that can only be captured using several imaging indexes pertaining to both brain structure and function.


Assuntos
Dislexia , Transtornos das Habilidades Motoras , Criança , Humanos , Transtornos das Habilidades Motoras/epidemiologia , Encéfalo , Neuroimagem Funcional , Comorbidade
14.
Neurosci Biobehav Rev ; 146: 105055, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36681370

RESUMO

Neuroticism is one of the most robust higher-order personality traits associated with negative emotionality and risk of mental disorders. Many studies have investigated relationships between neuroticism and the brain, but the results have been inconsistent. We conducted a meta-analysis of whole-brain resting-state functional neuroimaging studies to identify the most stable neurofunctional substrates of neuroticism. We found stable significant positive correlations between neuroticism and resting-state brain activity in the left middle temporal gyrus (MTG), left striatum, and right hippocampus. In contrast, resting-state brain activity in the left superior temporal gyrus (STG) and right supramarginal gyrus (SMG) was negatively associated with neuroticism. Additionally, meta-regression analysis revealed brain regions in which sex and age moderated the link of spontaneous activity with neuroticism. This is the first study to provide a comprehensive understanding of resting-state brain activity correlates of neuroticism, and the findings may be useful for the targeting of specific brain regions for interventions to decrease the risks of mental health problems.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Humanos , Neuroticismo , Imageamento por Ressonância Magnética/métodos , Encéfalo , Neuroimagem Funcional
15.
Mol Autism ; 14(1): 2, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627713

RESUMO

The long-described atypicalities of memory functioning experienced by people with autism have major implications for daily living, academic learning, as well as cognitive remediation. Though behavioral studies have identified a robust profile of memory strengths and weaknesses in autism spectrum disorder (ASD), few works have attempted to establish a synthesis concerning their neural bases. In this systematic review of functional neuroimaging studies, we highlight functional brain asymmetries in three anatomical planes during memory processing between individuals with ASD and typical development. These asymmetries consist of greater activity of the left hemisphere than the right in ASD participants, of posterior brain regions-including hippocampus-rather than anterior ones, and presumably of the ventral (occipito-temporal) streams rather than the dorsal (occipito-parietal) ones. These functional alterations may be linked to atypical memory processes in ASD, including the pre-eminence of verbal over spatial information, impaired active maintenance in working memory, and preserved relational memory despite poor context processing in episodic memory.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Transtorno Autístico/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Neuroimagem Funcional , Mapeamento Encefálico/métodos
16.
Eur Eat Disord Rev ; 31(3): 363-376, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36639902

RESUMO

OBJECTIVE: Functional neuroimaging studies have found differential neural activation patterns during anticipation-related paradigms in participants with eating disorders (EDs) compared to controls. However, publications reported conflicting results on the directionality and location of the abnormal activations. There is an urgent need to integrate our existing knowledge of anticipation, both rewarding and aversive, to elucidate these differences. METHOD: We conducted an activation likelihood estimation (ALE) meta-analysis to quantitatively review functional neuroimaging studies that evaluated differences between brain correlates of anticipation in participants with and without disordered eating. PubMed, Web of Sciences, PsycINFO, Medline and EMBASE were searched for studies published up to November 2022. Exploratory sub-analyses to check for differences between reward and non-reward anticipation among all anticipation paradigms. RESULTS: Twenty-one references met the inclusion criteria for meta-analysis. The meta-analysis across anticipation all tasks identified a significant hyperactivation cluster in the right putamen in participants with disordered eating (n = 17 experiments) and a significant hypoactivation cluster in the left inferior parietal lobule (n = 13 experiments), in participants with disordered eating compared to controls. CONCLUSIONS: These findings and sub-analyses of reward- and non-reward-related cues suggest potential pathophysiological mechanisms underlying anticipatory responses to rewarding and aversive cues in ED.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos , Imageamento por Ressonância Magnética , Humanos , Encéfalo , Neuroimagem Funcional , Afeto , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico por imagem
17.
J Affect Disord ; 325: 421-428, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36642308

RESUMO

BACKGROUND: The lack of effective objective diagnostic biomarkers for major depressive disorder (MDD) leads to high misdiagnosis. Compared with healthy controls (HC), abnormal brain functions and protein levels are often observed in MDD. However, it is unclear whether combining these changed multidimensional indicators could help improve the diagnosis of MDD. METHODS: Sixty-three MDD and eighty-one HC subjects underwent resting-state fMRI scans, among whom 37 MDD and 45 HC provided blood samples. Amplitudes of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), and serum levels of brain-derived neurotrophic factor (BDNF), cortisol, and multiple cytokines were measured and put into the linear discriminant analysis (LDA) to construct corresponding MDD diagnostic models. The area under the receiver operating characteristic curve (AUC) of 5-fold cross-validation was calculated to evaluate each model's performance. RESULTS: Compared with HC, MDD patients' spontaneous brain activity, serum BDNF, cortisol, interleukin (IL)-4, IL-6, and IL-10 levels changed significantly. The combinations of unidimensional multi-indicator had better diagnostic performance than a single one. The model consisted of multidimensional multi-indicator further exhibited conspicuously superior diagnostic efficiency than those constructed with unidimensional multi-indicator, and its AUC, sensitivity, specificity, and accuracy of 5-fold cross-validation were 0.99, 92.0 %, 100.0 %, and 96.3 %, respectively. LIMITATIONS: This cross-sectional study consists of relatively small samples and should be replicated in larger samples with follow-up data to optimize the diagnostic model. CONCLUSIONS: MDD patients' neuroimaging features and serum protein levels significantly changed. The model revealed by LDA could diagnose MDD with high accuracy, which may serve as an ideal diagnostic biomarker for MDD.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Fator Neurotrófico Derivado do Encéfalo , Estudos Transversais , Hidrocortisona , Encéfalo/diagnóstico por imagem , Neuroimagem Funcional , Imageamento por Ressonância Magnética/métodos
18.
Ageing Res Rev ; 85: 101859, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36669688

RESUMO

Impaired cognition is a known risk factor for falls in older adults. To enhance prevention strategies and treatment of falls among an aging global population, an understanding of the neural processes and networks involved is required. We present a systematic review investigating how functional neuroimaging techniques have been used to examine the association between falls and cognition in seniors. Peer-reviewed articles were identified through searching five electronic databases: 1) Medline, 2) PsycINFO, 3) CINAHL, 4) EMBASE, and 5) Pubmed. Key author, key paper, and reference searching was also conducted. Nine studies were included in this review. A questionnaire composed of seven questions was used to assess the quality of each study. EEG, fMRI, and PET were utilized across studies to examine brain function in older adults. Consistent evidence demonstrates that cognition is associated with measures of falls/falls risk, specifically visual attention and executive function. Our results show that falls/falls risk may be implicated with specific brain regions and networks. Future studies should be prospective and long-term in nature, with standardized outcome measures. Mobile neuroimaging techniques may also provide insight into brain activity as it pertains to cognition and falls in older adults in real-world settings.


Assuntos
Acidentes por Quedas , Disfunção Cognitiva , Humanos , Idoso , Acidentes por Quedas/prevenção & controle , Estudos Prospectivos , Cognição , Neuroimagem Funcional
19.
Eur J Pediatr ; 182(3): 1191-1200, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36607412

RESUMO

Reliably assessing the early neurodevelopmental outcomes in infants with neonatal encephalopathy (NE) is of utmost importance to advise parents and implement early and personalized interventions. We aimed to evaluate the accuracy of neuroimaging modalities, including functional magnetic resonance imaging (fMRI) in predicting neurodevelopmental outcomes in NE. Eighteen newborns with NE due to presumed perinatal asphyxia (PA) were included in the study, 16 of whom underwent therapeutic hypothermia. Structural magnetic resonance imaging (MRI), and fMRI during passive visual, auditory, and sensorimotor stimulation were acquired between the 10th and 14th day of age. Clinical follow-up protocol included visual and auditory evoked potentials and a detailed neurodevelopmental evaluation at 12 and 18 months of age. Infants were divided according to sensory and neurodevelopmental outcome: severe, moderate disability, or normal. Structural MRI findings were the best predictor of severe disability with an AUC close to 1.0. There were no good predictors to discriminate between moderate disability versus normal outcome. Nevertheless, structural MRI measures showed a significant correlation with the scores of neurodevelopmental assessments. During sensorimotor stimulation, the fMRI signal in the right hemisphere had an AUC of 0.9 to predict absence of cerebral palsy (CP). fMRI measures during auditory and visual stimulation did not predict sensorineural hearing loss or cerebral visual impairment. CONCLUSION: In addition to structural MRI, fMRI with sensorimotor stimulation may open the gate to improve the knowledge of neurodevelopmental/motor prognosis if proven in a larger cohort of newborns with NE. WHAT IS KNOWN: • Establishing an early, accurate neurodevelopmental prognosis in neonatal encephalopathy remains challenging. • Although structural MRI has a central role in neonatal encephalopathy, advanced MRI modalities are gradually being explored to optimize neurodevelopmental outcome knowledge. WHAT IS NEW: • Newborns who later developed cerebral palsy had a trend towards lower fMRI measures in the right sensorimotor area during sensorimotor stimulation. • These preliminary fMRI results may improve future early delineation of motor prognosis in neonatal encephalopathy.


Assuntos
Paralisia Cerebral , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Doenças do Recém-Nascido , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Paralisia Cerebral/diagnóstico por imagem , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Hipóxia-Isquemia Encefálica/terapia , Imageamento por Ressonância Magnética/métodos , Doenças do Recém-Nascido/terapia , Hipotermia Induzida/métodos , Neuroimagem Funcional
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...