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Neurovascular coupling and functional neuroimaging in epilepsy; Acoplamento neurovascular e neuroimagem funcional em epilepsia

BECKER JUNIOR, Valesio; WICHERT-ANA, Lauro; SILVA, Rhelen Piantino Leitão Ferreira da; ABUD, Daniel Giansante; ESCORSI-ROSSET, Sara; ROMCY-PEREIRA, Rodrigo; LEITE, João Pereira
Fonte: Liga Brasileira de Epilepsia (LBE) Publicador: Liga Brasileira de Epilepsia (LBE)
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.71%
INTRODUCTION: The neural regulation of the microcirculation is done by the functional neurovascular unit that is composed of vascular, astroglial and neuronal cells. The neurovascular unit represents the interface between the Central Nervous System and the Vascular System. OBJECTIVE: This paper reviews the literature on functional neuroimaging with a particular focus on the mechanisms of the neurovascular coupling. CONCLUSIONS: Functional neuroimaging techniques as functional MRI, SPECT and PET distinguish metabolic and physiological processes underlying normal and abnormal events, based on neurovascular coupling. Although these techniques still have limitations in temporal and spatial resolution, they have considerably reduced the need for intracranial electrodes or invasive functional tests in the presurgical evaluation for intractable epilepsy. Recently, new techniques as optical approaches (measurement of intrinsic optical signals and near infrared spectroscopy) have increased both temporal and spatial resolutions. The use of such techniques in animal models has yielded experimental evidence for a neurovascular coupling in normal and epileptic conditions.; INTRODUÇÃO: A regulação da microcirculação cerebral é realizada pela unidade neurovascular...

Traumatic memories: bridging the gap between functional neuroimaging and psychotherapy

PERES, Julio F. P.; MCFARLANE, Alexander; NASELLO, Antonia G.; MOORES, Kathryn A.
Fonte: INFORMA HEALTHCARE Publicador: INFORMA HEALTHCARE
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.71%
Objective: Neuroimaging studies have highlighted important issues related to structural and functional brain changes found in sufferers of psychological trauma that may influence their ability to synthesize, categorize, and integrate traumatic memories. Methods: Literature review and critical analysis and synthesis. Results: Traumatic memories are diagnostic symptoms of post-traumatic stress disorder (PTSD), and the dual representation theory posits separate memory systems subserving vivid re-experiencing (non-hippocampally dependent) versus declarative autobiographical memories of trauma (hippocampally dependent). But the psychopathological signs of trauma are not static over time, nor is the expression of traumatic memories. Multiple memory systems are activated simultaneously and in parallel on various occasions. Neural circuitry interaction is a crucial aspect in the development of a psychotherapeutic approach that may favour an integrative translation of the sensory fragments of the traumatic memory into a declarative memory system. Conclusion: The relationship between neuroimaging findings and psychological approaches is discussed for greater efficacy in the treatment of psychologically traumatized patients.

Can neuroimaging be used as a support to diagnosis of borderline personality disorder? An approach based on computational neuroanatomy and machine learning

Sato, Joao Ricardo; de Araujo Filho, Gerardo Maria; de Araujo, Thabata Bueno; Bressan, Rodrigo Affonsecca; de Oliveira, Pedro Paulo; Jackowski, Andrea Parolin
Fonte: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD Publicador: PERGAMON-ELSEVIER SCIENCE LTD; OXFORD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.71%
Several recent studies in literature have identified brain morphological alterations associated to Borderline Personality Disorder (BPD) patients. These findings are reported by studies based on voxel-based-morphometry analysis of structural MRI data, comparing mean gray-matter concentration between groups of BPD patients and healthy controls. On the other hand, mean differences between groups are not informative about the discriminative value of neuroimaging data to predict the group of individual subjects. In this paper, we go beyond mean differences analyses, and explore to what extent individual BPD patients can be differentiated from controls (25 subjects in each group), using a combination of automated-morphometric tools for regional cortical thickness/volumetric estimation and Support Vector Machine classifier. The approach included a feature selection step in order to identify the regions containing most discriminative information. The accuracy of this classifier was evaluated using the leave-one-subject-out procedure. The brain regions indicated as containing relevant information to discriminate groups were the orbitofrontal, rostral anterior cingulate, posterior cingulate, middle temporal cortices, among others. These areas...

Neuroimaging in specific phobia disorder: a systematic review of the literature; Neuroimagem do transtorno de fobia específica: uma revisão sistemática da literatura

Linares, Ila M.P; Trzesniak, Clarissa; Chagas, Marcos Hortes N; Hallak, Jaime E. C; Nardi, Antonio E; Crippa, José Alexandre S
Fonte: Associação Brasileira de Psiquiatria - ABP Publicador: Associação Brasileira de Psiquiatria - ABP
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.79%
OBJECTIVE: Specific phobia (SP) is characterized by irrational fear associated with avoidance of specific stimuli. In recent years, neuroimaging techniques have been used in an attempt to better understand the neurobiology of anxiety disorders. The objective of this study was to perform a systematic review of articles that used neuroimaging techniques to study SP. METHOD:A literature search was conducted through electronic databases, using the keywords: imaging, neuroimaging, PET, spectroscopy, functional magnetic resonance, structural magnetic resonance, SPECT, MRI, DTI, and tractography, combined with simple phobia and specific phobia. One-hundred fifteen articles were found, of which 38 were selected for the present review. From these, 24 used fMRI, 11 used PET, 1 used SPECT, 2 used structural MRI, and none used spectroscopy. RESULT: The search showed that studies in this area were published recently and that the neuroanatomic substrate of SP has not yet been consolidated. CONCLUSION: In spite of methodological differences among studies, results converge to a greater activation in the insula, anterior cingulate cortex, amygdala, and prefrontal and orbitofrontal cortex of patients exposed to phobia-related situations compared to controls. These findings support the hypotheses of the hyperactivation of a neuroanatomic structural network involved in SP.

Headache in childhood : clinical and neuroimaging evaluation = Cefaleia na infância: avaliação clínica e de neuroimagem; Cefaleia na infância : avaliação clínica e de neuroimagem

Karine Couto Sarmento Teixeira
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 31/07/2013 PT
Relevância na Pesquisa
36.93%
A cefaléia é uma condição extremamente prevalente em crianças e gera transtorno na vida familiar e escolar do seu portador. O objetivo geral do presente estudo foi caracterizar a frequência e tipos de cefaléia na infância, além de responder a algumas perguntas organizadas em subprojetos expostos abaixo. Foi realizada avaliação retrospectiva de prontuários, visando analisar os dados clínicos e de neuroimagem. As informações obtidas por análise de prontuários e complementadas em visitas de rotina. Os 674 pacientes estudados integraram um banco de dados, a partir do qual os resultados foram analisados e distribuídos em subprojetos. No subprojeto 1, verificamos o papel da investigação por neuroimagem nas cefaléias na infância. Foram incluídos 646 pacientes que apresentavam queixa de cefaléia e exame neurológico normal, a fim de avaliar o benefício da neuroimagem no diagnóstico e tratamento dessa patologia. Achados anormais de neuroimagem foram encontrados em 60 pacientes, classificados em três grupos: a) 9 pacientes com alterações relacionadas à patologia de base; b) 43 pacientes com alterações radiológicas benignas; e c) 8 pacientes com alterações radiológicas que mudaram a conduta médica. Desse último grupo...

Comparative study of the neuropsychological and neuroimaging evaluations in children with dyslexia

Arduini,Rodrigo Genaro; Capellini,Simone Aparecida; Ciasca,Sylvia Maria
Fonte: Academia Brasileira de Neurologia - ABNEURO Publicador: Academia Brasileira de Neurologia - ABNEURO
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2006 EN
Relevância na Pesquisa
36.71%
We analyzed retrospectively the neuroimaging exams of children with a confirmed diagnosis of dyslexia and correlated our findings with the evaluation of higher cortical functions. We studied 34 medical files of patients of the Ambulatory of Neuro-difficulties in Learning, FCM/UNICAMP. All of them had been sent to the ambulatory with primary or secondary complaints of difficulties at school and were submitted to neuropsychological evaluation and imaging exam (SPECT). From the children evaluated 58.8% had exams presenting dysfunction with 47% presenting hypoperfusion in the temporal lobe. As for the higher cortical functions, the most affected abilities were reading, writing and memory. There was significance between the hypoperfused areas and the variables schooling, reading, writing, memory and mathematic reasoning. The SPECTs showed hypoperfusion in areas involved in the reading and writing processes. Both are equivalent in terms of involved functional areas and are similar in children with or without specific dysfunctions in neuroimaging.

Effects of bariatric surgery on the central nervous system and eating behavior in humans: a systematic review on the neuroimaging studies

Tonelli,Hélio; Sartori,Fernanda Mattias; Marchesini,João Caetano Dallegrave; Marchesini,João Batista; Tonelli,Denise Gianoti
Fonte: Instituto de Psiquiatria da Universidade Federal do Rio de Janeiro Publicador: Instituto de Psiquiatria da Universidade Federal do Rio de Janeiro
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2013 EN
Relevância na Pesquisa
36.79%
INTRODUCTION: Neuroimaging studies suggest that obese people might show hyperactivity of brain areas regarding reward processing, and hypoactivity of brain areas concerning cognitive control, when exposed to food cues. Although the effects of bariatric surgery on the central nervous system and eating behavior are well known, few studies have used neuroimage techniques with the aim of investigating the central effects of bariatric surgery in humans. OBJECTIVES: This paper systematically and critically reviews studies using functional neuroimaging to investigate changes on the patterns of activation of central areas related to the regulation of eating behavior after bariatric surgery. METHOD: A search on the databases Medline, Web of Science, Lilacs and Science Direct on Line, was conducted in February 2013, using the keywords "Neuroimaging", "Positron-Emission Tomography", "Magnetic Resonance Imaging", "Gastric Bypass", "Gastroplasty", "Jejunoileal Bypass", "Bariatric Surgery". RESULTS: Seven manuscripts were included; the great majority studied the central effects of Roux en Y gastric bypass, using positron emission tomography or functional magnetic resonance. CONCLUSIONS: Bariatric surgery might normalize the activity of central areas concerned with reward and incentive salience processing...

Neuroimaging in specific phobia disorder: a systematic review of the literature

Linares,Ila M.P; Trzesniak,Clarissa; Chagas,Marcos Hortes N; Hallak,Jaime E. C; Nardi,Antonio E; Crippa,José Alexandre S
Fonte: Associação Brasileira de Psiquiatria - ABP Publicador: Associação Brasileira de Psiquiatria - ABP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2012 EN
Relevância na Pesquisa
36.79%
OBJECTIVE: Specific phobia (SP) is characterized by irrational fear associated with avoidance of specific stimuli. In recent years, neuroimaging techniques have been used in an attempt to better understand the neurobiology of anxiety disorders. The objective of this study was to perform a systematic review of articles that used neuroimaging techniques to study SP. METHOD:A literature search was conducted through electronic databases, using the keywords: imaging, neuroimaging, PET, spectroscopy, functional magnetic resonance, structural magnetic resonance, SPECT, MRI, DTI, and tractography, combined with simple phobia and specific phobia. One-hundred fifteen articles were found, of which 38 were selected for the present review. From these, 24 used fMRI, 11 used PET, 1 used SPECT, 2 used structural MRI, and none used spectroscopy. RESULT: The search showed that studies in this area were published recently and that the neuroanatomic substrate of SP has not yet been consolidated. CONCLUSION: In spite of methodological differences among studies, results converge to a greater activation in the insula, anterior cingulate cortex, amygdala, and prefrontal and orbitofrontal cortex of patients exposed to phobia-related situations compared to controls. These findings support the hypotheses of the hyperactivation of a neuroanatomic structural network involved in SP.

The involvement of the orbitofrontal cortex in psychiatric disorders: an update of neuroimaging findings

Jackowski,Andrea Parolin; Filho,Gerardo Maria de Araújo; Almeida,Amanda Galvão de; Araújo,Célia Maria de; Reis,Marília; Nery,Fabiana; Batista,Ilza Rosa; Silva,Ivaldo; Lacerda,Acioly L. T.
Fonte: Associação Brasileira de Psiquiatria - ABP Publicador: Associação Brasileira de Psiquiatria - ABP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
Relevância na Pesquisa
36.71%
OBJECTIVE: To report structural and functional neuroimaging studies exploring the potential role of the orbitofrontal cortex (OFC) in the pathophysiology of the most prevalent psychiatric disorders (PD). METHOD: A non-systematic literature review was conducted by means of MEDLINE using the following terms as parameters: "orbitofrontal cortex", "schizophrenia", "bipolar disorder", "major depression", "anxiety disorders", "personality disorders" and "drug addiction". The electronic search was done up to July 2011. DISCUSSION: Structural and functional OFC abnormalities have been reported in many PD, namely schizophrenia, mood disorders, anxiety disorders, personality disorders and drug addiction. Structural magnetic resonance imaging studies have reported reduced OFC volume in patients with schizophrenia, mood disorders, PTSD, panic disorder, cluster B personality disorders and drug addiction. Furthermore, functional magnetic resonance imaging studies using cognitive paradigms have shown impaired OFC activity in all PD listed above. CONCLUSION: Neuroimaging studies have observed an important OFC involvement in a number of PD. However, future studies are clearly needed to characterize the specific role of OFC on each PD as well as understanding its role in both normal and pathological behavior...

Structural and functional neuroimaging findings associated with the use of clozapine in schizophrenia: a systematic review

Garcia,Giovana J.; Chagas,Marcos H.; Silva,Carlos H.; Machado-de-Sousa,João P.; Crippa,José A.; Hallak,Jaime E.
Fonte: Associação Brasileira de Psiquiatria - ABP Publicador: Associação Brasileira de Psiquiatria - ABP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 EN
Relevância na Pesquisa
36.9%
Objective: Schizophrenia is one of the most severe psychiatric disorders, and its current treatment relies on antipsychotic medications with only partial effectiveness. Clozapine is an atypical antipsychotic with a specific profile of action indicated for treatment-resistant schizophrenia. Neuroimaging studies assessing the effects of clozapine could help shed light on the neural underpinnings of the effects of this drug in the brain. The objective of this study was to review the available literature on the structural and functional neuroimaging findings associated with use of clozapine. Method: We conducted a systematic review of the indexed literature using the PubMed, BIREME, and ISI Web of Knowledge search engines and the following keywords: clozapine, neuroimaging, computed tomography, MRI, functional magnetic resonance, PET, SPECT, and DTI. Results: A total of 23 articles were included in the review. In structural studies, the use of clozapine was associated with volume reductions in the basal ganglia, especially the caudate nucleus, where functional neuroimaging studies also found decreased perfusion. In the frontal lobe, clozapine treatment was associated with increased gray matter volume and reduced perfusion. Conclusion: The results of the studies reviewed suggest that the use of clozapine is associated with distinctive structural and functional neuroimaging findings that are not shared with other antipsychotics.

Neurovascular coupling and functional neuroimaging in epilepsy

Becker Junior,Valesio; Wichert-Ana,Lauro; Silva,Rhelen Piantino Leitão Ferreira da; Abud,Daniel Giansante; Escorsi-Rosset,Sara; Romcy-Pereira,Rodrigo; Leite,João Pereira
Fonte: Liga Brasileira de Epilepsia (LBE) Publicador: Liga Brasileira de Epilepsia (LBE)
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2009 EN
Relevância na Pesquisa
36.71%
INTRODUCTION: The neural regulation of the microcirculation is done by the functional neurovascular unit that is composed of vascular, astroglial and neuronal cells. The neurovascular unit represents the interface between the Central Nervous System and the Vascular System. OBJECTIVE: This paper reviews the literature on functional neuroimaging with a particular focus on the mechanisms of the neurovascular coupling. CONCLUSIONS: Functional neuroimaging techniques as functional MRI, SPECT and PET distinguish metabolic and physiological processes underlying normal and abnormal events, based on neurovascular coupling. Although these techniques still have limitations in temporal and spatial resolution, they have considerably reduced the need for intracranial electrodes or invasive functional tests in the presurgical evaluation for intractable epilepsy. Recently, new techniques as optical approaches (measurement of intrinsic optical signals and near infrared spectroscopy) have increased both temporal and spatial resolutions. The use of such techniques in animal models has yielded experimental evidence for a neurovascular coupling in normal and epileptic conditions.

The ENIGMA Consortium: large-scale collaborative analyses of neuroimaging and genetic data

Thompson, Paul M.; Stein, Jason L.; Medland, Sarah E.; Hibar, Derrek P.; Vasquez, Alejandro Arias; Renteria, Miguel E.; Toro, Roberto; Jahanshad, Neda; Schumann, Gunter; Franke, Barbara; Wright, Margaret J.; Martin, Nicholas G.; Agartz, Ingrid; Alda, Mart
Fonte: Springer US Publicador: Springer US
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
36.79%
The Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Consortium is a collaborative network of researchers working together on a range of large-scale studies that integrate data from 70 institutions worldwide. Organized into Working Groups that tackle questions in neuroscience, genetics, and medicine, ENIGMA studies have analyzed neuroimaging data from over 12,826 subjects. In addition, data from 12,171 individuals were provided by the CHARGE consortium for replication of findings, in a total of 24,997 subjects. By meta-analyzing results from many sites, ENIGMA has detected factors that affect the brain that no individual site could detect on its own, and that require larger numbers of subjects than any individual neuroimaging study has currently collected. ENIGMA’s first project was a genome-wide association study identifying common variants in the genome associated with hippocampal volume or intracranial volume. Continuing work is exploring genetic associations with subcortical volumes (ENIGMA2) and white matter microstructure (ENIGMA-DTI). Working groups also focus on understanding how schizophrenia, bipolar illness, major depression and attention deficit/hyperactivity disorder (ADHD) affect the brain. We review the current progress of the ENIGMA Consortium...

Traumatic memories: bridging the gap between functional neuroimaging and psychotherapy

Peres, J.; McFarlane, A.; Nasello, A.; Moores, K.
Fonte: Blackwell Publishing Asia Publicador: Blackwell Publishing Asia
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
Relevância na Pesquisa
36.71%
Objective: Neuroimaging studies have highlighted important issues related to structural and functional brain changes found in sufferers of psychological trauma that may influence their ability to synthesize, categorize, and integrate traumatic memories. Methods: Literature review and critical analysis and synthesis. Results: Traumatic memories are diagnostic symptoms of post-traumatic stress disorder (PTSD), and the dual representation theory posits separate memory systems subserving vivid re-experiencing (non-hippocampally dependent) versus declarative autobiographical memories of trauma (hippocampally dependent). But the psychopathological signs of trauma are not static over time, nor is the expression of traumatic memories. Multiple memory systems are activated simultaneously and in parallel on various occasions. Neural circuitry interaction is a crucial aspect in the development of a psychotherapeutic approach that may favour an integrative translation of the sensory fragments of the traumatic memory into a declarative memory system. Conclusion: The relationship between neuroimaging findings and psychological approaches is discussed for greater efficacy in the treatment of psychologically traumatized patients.; Julio F. P. Peres...

Assessment of the quality of brain regions and neuroimaging metrics as biomarkers of Alzheimer’s disease

Vaz, Tânia; Lucena, Filipa; Pé-Leve, Joana; Ribeiro, André Santos; Lacerda, Luís; Silva, Nuno da; Nutt, David; McGonigle, John; Ferreira, Hugo Alexandre
Fonte: Springer Publicador: Springer
Tipo: Conferência ou Objeto de Conferência
Publicado em /05/2015 ENG
Relevância na Pesquisa
36.9%
Alzheimer Disease (AD) is characterized by progressive cognitive decline and dementia. Earlier diagnosis and classification of different stages of the disease are currently the main challenges and can be assessed by neuroimaging. With this work we aim to evaluate the quality of brain regions and neuroimaging metrics as biomarkers of AD. Multimodal Imaging Brain Connectivity Analysis (MIBCA) toolbox functionalities were used to study AD by T1weighted, Diffusion Tensor Imaging and 18FAV45 PET, with data obtained from the AD Neuroimaging Initiative database, specifically 12 healthy controls (CTRL) and 33 patients with early mild cognitive impairment (EMCI), late MCI (LMCI) and AD (11 patients/group). The metrics evaluated were gray-matter volume (GMV), cortical thickness (CThk), mean diffusivity (MD), fractional anisotropy (FA), fiber count (FiberConn), node degree (Deg), cluster coefficient (ClusC) and relative standard-uptake-values (rSUV). Receiver Operating Characteristic (ROC) curves were used to evaluate and compare the diagnostic accuracy of the most significant metrics and brain regions and expressed as area under the curve (AUC). Comparisons were performed between groups. The RH-Accumbens/Deg demonstrated the highest AUC when differentiating between CTRLEMCI (82%)...

Neuroimaging in Alzheimer's disease: current role in clinical practice and potential future applications

FERREIRA, Luiz Kobuti; BUSATTO, Geraldo F.
Fonte: Faculdade de Medicina / USP Publicador: Faculdade de Medicina / USP
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.71%
'Alzheimer's disease is the most common cause of dementia and its prevalence is expected to increase in the coming years. Therefore, accurate diagnosis is crucial for patients, clinicians and researchers. Neuroimaging techniques have provided invaluable information about Alzheimer's disease and, owing to recent advances, these methods will have an increasingly important role in research and clinical practice. The purpose of this article is to review recent neuroimaging studies of Alzheimer's disease that provide relevant information to clinical practice, including a new modality: in vivo amyloid imaging. Magnetic resonance imaging, single photon emission computed tomography and 18F-fluorodeoxyglucose-positron emission tomography are currently available for clinical use. Patients with suspected Alzheimer's disease are commonly investigated with magnetic resonance imaging because it provides detailed images of brain structure and allows the identification of supportive features for the diagnosis. Neurofunctional techniques such as single photon emission computed tomography and 18F-fluorodeoxyglucose-positron emission tomography can also be used to complement the diagnostic investigation in cases of uncertainty. Amyloid imaging is a non-invasive technique that uses positron emission tomography technology to investigate the accumulation of the β-amyloid peptide in the brain...

Neuroimaging and neuromodulation approaches to study eating behavior and prevent and treat eating disorders and obesity

Val-Laillet, D.; Aarts, E.; Weber, B.; Ferrari, M.; Quaresima, V.; Stoeckel, L.E.; Alonso-Alonso, M.; Audette, M.; Malbert, C.H.; Stice, E.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
36.9%
Functional, molecular and genetic neuroimaging has highlighted the existence of brain anomalies and neural vulnerability factors related to obesity and eating disorders such as binge eating or anorexia nervosa. In particular, decreased basal metabolism in the prefrontal cortex and striatum as well as dopaminergic alterations have been described in obese subjects, in parallel with increased activation of reward brain areas in response to palatable food cues. Elevated reward region responsivity may trigger food craving and predict future weight gain. This opens the way to prevention studies using functional and molecular neuroimaging to perform early diagnostics and to phenotype subjects at risk by exploring different neurobehavioral dimensions of the food choices and motivation processes. In the first part of this review, advantages and limitations of neuroimaging techniques, such as functional magnetic resonance imaging (fMRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), pharmacogenetic fMRI and functional near-infrared spectroscopy (fNIRS) will be discussed in the context of recent work dealing with eating behavior, with a particular focus on obesity. In the second part of the review, non-invasive strategies to modulate food-related brain processes and functions will be presented. At the leading edge of non-invasive brain-based technologies is real-time fMRI (rtfMRI) neurofeedback...

Neuroimaging of structural pathology and connectomics in traumatic brain injury: Toward personalized outcome prediction☆

Irimia, Andrei; Wang, Bo; Aylward, Stephen R.; Prastawa, Marcel W.; Pace, Danielle F.; Gerig, Guido; Hovda, David A.; Kikinis, Ron; Vespa, Paul M.; Van Horn, John D.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
36.85%
Recent contributions to the body of knowledge on traumatic brain injury (TBI) favor the view that multimodal neuroimaging using structural and functional magnetic resonance imaging (MRI and fMRI, respectively) as well as diffusion tensor imaging (DTI) has excellent potential to identify novel biomarkers and predictors of TBI outcome. This is particularly the case when such methods are appropriately combined with volumetric/morphometric analysis of brain structures and with the exploration of TBI-related changes in brain network properties at the level of the connectome. In this context, our present review summarizes recent developments on the roles of these two techniques in the search for novel structural neuroimaging biomarkers that have TBI outcome prognostication value. The themes being explored cover notable trends in this area of research, including (1) the role of advanced MRI processing methods in the analysis of structural pathology, (2) the use of brain connectomics and network analysis to identify outcome biomarkers, and (3) the application of multivariate statistics to predict outcome using neuroimaging metrics. The goal of the review is to draw the community's attention to these recent advances on TBI outcome prediction methods and to encourage the development of new methodologies whereby structural neuroimaging can be used to identify biomarkers of TBI outcome.

Multiple Testing for Neuroimaging via Hidden Markov Random Field

Shu, Hai; Nan, Bin; Koeppe, Robert; Initiative, the Alzheimer's Disease Neuroimaging
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 04/04/2014
Relevância na Pesquisa
36.79%
One of the important objectives that the Alzheimer's Disease Neuroimaging Initiative (ADNI) tries to achieve is to understand how the human brain changes over the course of disease progression. We consider voxel-level analysis for the 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET) imaging study in ADNI for such a purpose. Traditional voxel-level multiple testing procedures in neuroimaging, which are mostly p-value based, often ignore the spatial correlations among neighboring voxels and thus suffer from substantial loss of power. We extend the local-significance-index based procedure, which aims to minimize the false nondiscovery rate subject to a constraint on the false discovery rate, to three-dimensional neuroimaging data using a hidden Markov random field model. A generalized expectation-maximization algorithm is proposed for estimating the model parameters. Extensive simulations show that the proposed approach is more powerful than conventional false discovery rate procedures. We apply the method to the comparison between mild cognitive impairment, a disease status with increased risk of developing Alzheimer's or another dementia, and normal controls in the ADNI's FDG-PET imaging study.

Achados da neuroimagem em transtorno de estresse pós-traumático e suas implicações clínicas; Posttraumatic stress disorder neuroimaging findings and their clinical implications

Peres, Julio Fernando Prieto; Nasello, Antonia Gladys
Fonte: Universidade de São Paulo. Faculdade de Medicina. Instituto de Psiquiatria Publicador: Universidade de São Paulo. Faculdade de Medicina. Instituto de Psiquiatria
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; Formato: application/pdf
Publicado em 01/07/2005 POR
Relevância na Pesquisa
36.79%
Estudos com neuroimagem vêm replicando alguns achados relevantes ao entendimento de anormalidades neuroanatômicas, estruturais e funcionais associadas ao transtorno de estresse pós-traumático (TEPT). A dificuldade em sintetizar, categorizar e integrar a memória traumática em uma narrativa pode estar relacionada à relativa diminuição do volume e ativação do hipocampo, à diminuição na atividade do córtex pré-frontal, do cíngulo anterior e da área de Broca. O mecanismo deficiente de extinção da resposta ao medo e à desregulação emocional estão possivelmente relacionados à menor atividade cortical pré-frontal, implicado na atenuação do feedback negativo da atividade da amígdala. Tais memórias traumáticas não-hipocampo/pré-frontal dependentes são involuntariamente acessadas, apresentam-se fragmentadas sensorialmente, sem estrutura narrativa desenvolvida e tendem a permanecer com expressão emocional intensa e sensações vívidas. Processos psicoterapêuticos, baseados em exposição e reconstrução cognitiva, podem estimular as faculdades cognitivas e integrativas do encéfalo correspondentes às estruturas encontradas como deficitárias em indivíduos com TEPT. Nessa perspectiva, a memória poderá perder intensidade emocional...

Working memory and the brain: a review of models, and clinical and neuroimaging studies; Working memory and the brain: a review of models, and clinical and neuroimaging studies

Buchweitz, Augusto
Fonte: Editora da UFSC Publicador: Editora da UFSC
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 01/01/2003 POR
Relevância na Pesquisa
36.85%
This paper presents a review of literature aimed at a general discussion on memory, working memory (WM) and the brain, based on a three-pronged source of evidence from clinical, behavioral, and, more importantly, neuroimaging studies. The review is organized following an initial, threefold discussion on (1) the segmentation of memory; (2) WM models; and (3) the prefrontal cortex; in the fourth section it resorts to neuroimaging studies. The objective is to illustrate what possible contributions have already been, and still can be, derived from neuroimaging within the study and modeling of WM, with previous theories and findings as the starting point.; Este artigo apresenta uma revisão de literatura que busca incitar uma discussão geral sobre a memória de trabalho (MT) e o cérebro humano, utilizando-se de referências variadas de estudos clínicos, comportamentais e de neuroimagem. A revisão seguirá os seguintes passos: primeiro, uma discussão sobre (1) a segmentação da memória, (2) os modelos de memória de trabalho e (3) o córtex pré-frontal e a MT; em um segundo momento, com base na discussão anterior, parte-se para uma discussão sobre estudos de neuroimagem relacionados à MT. O objetivo do artigo é iluminar as possíveis contribuições que já foram e que ainda podem ser feitas pelos estudos de neuroimagem aos estudos e aos modelos que buscam melhor entender a MT.