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1.
Am J Perinatol ; 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37973154

RESUMEN

OBJECTIVE: Evaluate the pain of critically ill newborns is a challenge because of the devices for cardiorespiratory support. This study aim to verify the adults' gaze when assessing the critically ill neonates' pain at bedside. STUDY DESIGN: Cross-sectional study in which pediatricians, nursing technicians, and parents evaluated critically ill neonates' pain at bedside, for 20 seconds with eye-tracking glasses. At the end, they answered whether the neonate was in pain or not. Visual tracking outcomes: number and time of visual fixations in four areas of interest (AOI) (face, trunk, and upper [UL] and lower [LL] limbs) were compared between groups and according to pain perception (present/absent). RESULTS: A total of 62 adults (21 pediatricians, 23 nursing technicians, 18 parents) evaluated 27 neonates (gestational age: 31.8 ± 4.4 weeks; birth weight: 1,645 ± 1,234 g). More adults fixed their gaze on the face (96.8%) and trunk (96.8%), followed by UL (74.2%) and LL (66.1%). Parents performed a greater number of fixations on the trunk than nursing technicians (11.0 vs. 5.5 vs. 6.0; p = 0.023). Controlled for visual tracking variables, each second of eye fixation in AOI (1.21; 95% confidence interval [CI]: 1.03-1.42; p = 0.018) and UL (1.07; 95% CI: 1.03-1.10; p < 0.001) increased the chance of perceiving the presence of pain. CONCLUSION: Adults, when assessing at bedside critically ill newborns' pain, fixed their eyes mainly on the face and trunk. The time spent looking at the UL was associated with the perception of pain presence. KEY POINTS: · Pain assessment in critically ill newborns is a challenge.. · To assess critically ill neonates' pain, adults mainly look at the face and trunk.. · Looking at the upper limbs also helps in assessing critically ill neonates' pain..

2.
Neuroimage ; 67: 203-12, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23165323

RESUMEN

The use of magnetoencephalography (MEG) to assess long range functional connectivity across large scale distributed brain networks is gaining popularity. Recent work has shown that electrodynamic networks can be assessed using both seed based correlation or independent component analysis (ICA) applied to MEG data and further that such metrics agree with fMRI studies. To date, techniques for MEG connectivity assessment have typically used a variance normalised approach, either through the use of Pearson correlation coefficients or via variance normalisation of envelope timecourses prior to ICA. Here, we show that the use of variance information (i.e. data that have not been variance normalised) in source space projected Hilbert envelope time series yields important spatial information, and is of significant functional relevance. Further, we show that employing this information in functional connectivity analyses improves the spatial delineation of network nodes using both seed based and ICA approaches. The use of variance is particularly important in MEG since the non-independence of source space voxels (brought about by the ill-posed MEG inverse problem) means that spurious signals can exist in areas of low signal variance. We therefore suggest that this approach be incorporated into future studies.


Asunto(s)
Algoritmos , Mapeo Encefálico/métodos , Encéfalo/fisiología , Conectoma/métodos , Magnetoencefalografía/métodos , Memoria/fisiología , Red Nerviosa/fisiología , Análisis de Varianza , Humanos , Análisis de Componente Principal
3.
J Pediatr (Rio J) ; 99(6): 546-560, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37331703

RESUMEN

OBJECTIVE: To describe the challenges and perspectives of the automation of pain assessment in the Neonatal Intensive Care Unit. DATA SOURCES: A search for scientific articles published in the last 10 years on automated neonatal pain assessment was conducted in the main Databases of the Health Area and Engineering Journal Portals, using the descriptors: Pain Measurement, Newborn, Artificial Intelligence, Computer Systems, Software, Automated Facial Recognition. SUMMARY OF FINDINGS: Fifteen articles were selected and allowed a broad reflection on first, the literature search did not return the various automatic methods that exist to date, and those that exist are not effective enough to replace the human eye; second, computational methods are not yet able to automatically detect pain on partially covered faces and need to be tested during the natural movement of the neonate and with different light intensities; third, for research to advance in this area, databases are needed with more neonatal facial images available for the study of computational methods. CONCLUSION: There is still a gap between computational methods developed for automated neonatal pain assessment and a practical application that can be used at the bedside in real-time, that is sensitive, specific, and with good accuracy. The studies reviewed described limitations that could be minimized with the development of a tool that identifies pain by analyzing only free facial regions, and the creation and feasibility of a synthetic database of neonatal facial images that is freely available to researchers.


Asunto(s)
Inteligencia Artificial , Unidades de Cuidado Intensivo Neonatal , Recién Nacido , Humanos , Dolor/diagnóstico , Dimensión del Dolor/métodos
4.
Neuroimage ; 52(4): 1444-55, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20472076

RESUMEN

The identification, modeling, and analysis of interactions between nodes of neural systems in the human brain have become the aim of interest of many studies in neuroscience. The complex neural network structure and its correlations with brain functions have played a role in all areas of neuroscience, including the comprehension of cognitive and emotional processing. Indeed, understanding how information is stored, retrieved, processed, and transmitted is one of the ultimate challenges in brain research. In this context, in functional neuroimaging, connectivity analysis is a major tool for the exploration and characterization of the information flow between specialized brain regions. In most functional magnetic resonance imaging (fMRI) studies, connectivity analysis is carried out by first selecting regions of interest (ROI) and then calculating an average BOLD time series (across the voxels in each cluster). Some studies have shown that the average may not be a good choice and have suggested, as an alternative, the use of principal component analysis (PCA) to extract the principal eigen-time series from the ROI(s). In this paper, we introduce a novel approach called cluster Granger analysis (CGA) to study connectivity between ROIs. The main aim of this method was to employ multiple eigen-time series in each ROI to avoid temporal information loss during identification of Granger causality. Such information loss is inherent in averaging (e.g., to yield a single "representative" time series per ROI). This, in turn, may lead to a lack of power in detecting connections. The proposed approach is based on multivariate statistical analysis and integrates PCA and partial canonical correlation in a framework of Granger causality for clusters (sets) of time series. We also describe an algorithm for statistical significance testing based on bootstrapping. By using Monte Carlo simulations, we show that the proposed approach outperforms conventional Granger causality analysis (i.e., using representative time series extracted by signal averaging or first principal components estimation from ROIs). The usefulness of the CGA approach in real fMRI data is illustrated in an experiment using human faces expressing emotions. With this data set, the proposed approach suggested the presence of significantly more connections between the ROIs than were detected using a single representative time series in each ROI.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Potenciales Evocados/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Red Nerviosa/fisiología , Vías Nerviosas/fisiología , Algoritmos , Análisis por Conglomerados , Humanos , Aumento de la Imagen/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
J. pediatr. (Rio J.) ; 99(6): 546-560, 2023. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1521159

RESUMEN

Abstract Objective: To describe the challenges and perspectives of the automation of pain assessment in the Neonatal Intensive Care Unit. Data sources: A search for scientific articles published in the last 10 years on automated neonatal pain assessment was conducted in the main Databases of the Health Area and Engineering Journal Portals, using the descriptors: Pain Measurement, Newborn, Artificial Intelligence, Computer Systems, Software, Automated Facial Recognition. Summary of findings: Fifteen articles were selected and allowed a broad reflection on first, the literature search did not return the various automatic methods that exist to date, and those that exist are not effective enough to replace the human eye; second, computational methods are not yet able to automatically detect pain on partially covered faces and need to be tested during the natural movement of the neonate and with different light intensities; third, for research to advance in this area, databases are needed with more neonatal facial images available for the study of computational methods. Conclusion: There is still a gap between computational methods developed for automated neonatal pain assessment and a practical application that can be used at the bedside in real-time, that is sensitive, specific, and with good accuracy. The studies reviewed described limitations that could be minimized with the development of a tool that identifies pain by analyzing only free facial regions, and the creation and feasibility of a synthetic database of neonatal facial images that is freely available to researchers.

6.
Psychiatry Res ; 233(2): 289-91, 2015 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-26187550

RESUMEN

Standard functional magnetic resonance imaging (fMRI) analyses cannot assess the potential of a neuroimaging signature as a biomarker to predict individual vulnerability to major depression (MD). Here, we use machine learning for the first time to address this question. Using a recently identified neural signature of guilt-selective functional disconnection, the classification algorithm was able to distinguish remitted MD from control participants with 78.3% accuracy. This demonstrates the high potential of our fMRI signature as a biomarker of MD vulnerability.


Asunto(s)
Algoritmos , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/fisiopatología , Diagnóstico por Computador , Imagen Eco-Planar/métodos , Interpretación de Imagen Asistida por Computador/métodos , Aprendizaje Automático , Imagen por Resonancia Magnética/métodos , Adulto , Biomarcadores , Estudios de Casos y Controles , Femenino , Culpa , Humanos , Masculino , Red Nerviosa/fisiopatología , Valores de Referencia , Sensibilidad y Especificidad , Lóbulo Temporal/fisiopatología
7.
Soc Neurosci ; 6(5-6): 627-39, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21590586

RESUMEN

BACKGROUND: Psychopathy is a disorder of personality characterized by severe impairments of social conduct, emotional experience, and interpersonal behavior. Psychopaths consistently violate social norms and bring considerable financial, emotional, or physical harm to others and to society as a whole. Recent developments in analysis methods of magnetic resonance imaging (MRI), such as voxel-based-morphometry (VBM), have become major tools to understand the anatomical correlates of this disorder. Nevertheless, the identification of psychopathy by neuroimaging or other neurobiological tools (e.g., genetic testing) remains elusive. METHODS/PRINCIPAL FINDINGS: The main aim of this study was to develop an approach to distinguish psychopaths from healthy controls, based on the integration between pattern recognition methods and gray matter quantification. We employed support vector machines (SVM) and maximum uncertainty linear discrimination analysis (MLDA), with a feature-selection algorithm. Imaging data from 15 healthy controls and 15 psychopathic individuals (7 women in each group) were analyzed with SPM2 and the optimized VBM preprocessing routines. Participants were scanned with a 1.5 Tesla MRI system. Both SVM and MLDA achieved an overall leave-one-out accuracy of 80%, but SVM mapping was sparser than using MLDA. The superior temporal sulcus/gyrus (bilaterally) was identified as a region containing the most relevant information to separate the two groups. CONCLUSION/SIGNIFICANCE: These results indicate that gray matter quantitative measures contain robust information to predict high psychopathy scores in individual subjects. The methods employed herein might prove useful as an adjunct to the established clinical and neuropsychological measures in patient screening and diagnostic accuracy.


Asunto(s)
Trastorno de Personalidad Antisocial/diagnóstico , Mapeo Encefálico/métodos , Encéfalo/patología , Interpretación de Imagen Asistida por Computador/métodos , Máquina de Vectores de Soporte , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino
8.
Artif Intell Med ; 49(2): 105-15, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20452195

RESUMEN

OBJECTIVE: The aim of this article is to propose an integrated framework for extracting and describing patterns of disorders from medical images using a combination of linear discriminant analysis and active contour models. METHODS: A multivariate statistical methodology was first used to identify the most discriminating hyperplane separating two groups of images (from healthy controls and patients with schizophrenia) contained in the input data. After this, the present work makes explicit the differences found by the multivariate statistical method by subtracting the discriminant models of controls and patients, weighted by the pooled variance between the two groups. A variational level-set technique was used to segment clusters of these differences. We obtain a label of each anatomical change using the Talairach atlas. RESULTS: In this work all the data was analysed simultaneously rather than assuming a priori regions of interest. As a consequence of this, by using active contour models, we were able to obtain regions of interest that were emergent from the data. The results were evaluated using, as gold standard, well-known facts about the neuroanatomical changes related to schizophrenia. Most of the items in the gold standard was covered in our result set. CONCLUSIONS: We argue that such investigation provides a suitable framework for characterising the high complexity of magnetic resonance images in schizophrenia as the results obtained indicate a high sensitivity rate with respect to the gold standard.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/patología , Análisis Discriminante , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Modelos Estadísticos , Esquizofrenia/diagnóstico , Algoritmos , Automatización de Laboratorios , Estudios de Casos y Controles , Interpretación Estadística de Datos , Humanos , Modelos Lineales , Valor Predictivo de las Pruebas , Esquizofrenia/patología , Sensibilidad y Especificidad
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