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1.
Rev. colomb. anestesiol ; 49(2): e201, Apr.-June 2021. tab, graf
Article in English | LILACS, COLNAL | ID: biblio-1251498

ABSTRACT

Abstract Introduction The analysis of the electrical activity of the brain using scalp electrodes with electroencephalography (EEG) could reveal the depth of anesthesia of a patient during surgery. However, conventional EEG equipment, due to its price and size, are not a practical option for the operating room and the commercial units used in surgery do not provide access to the electrical activity. The availability of low-cost portable technologies could provide for further research on the brain activity under general anesthesia and facilitate our quest for new markers of depth of anesthesia. Objective To assess the capabilities of a portable EEG technology to capture brain rhythms associated with the state of consciousness and the general anesthesia status of surgical patients anesthetized with propofol. Methods Observational, cross-sectional study that reviewed 10 EEG recordings captured using OpenBCI portable low-cost technology, in female patients undergoing general anesthesia with propofol. The signal from the frontal electrodes was analyzed with spectral analysis and the results were compared against the reports in the literature. Results The signal captured with frontal electrodes, particularly α rhythm, enabled the distinction between resting with eyes closed and with eyes opened in a conscious state, and sustained anesthesia during surgery. Conclusions It is possible to differentiate a resting state from sustained anesthesia, replicating previous findings with conventional technologies. These results pave the way to the use of portable technologies such as the OpenBCI tool, to explore the brain dynamics during anesthesia.


Resumen Introducción El análisis de la actividad eléctrica cerebral mediante electrodos ubicados sobre el cuero cabelludo con electroencefalografía (EEG) podría permitir conocer la profundidad anestésica de un paciente durante cirugía. Sin embargo, los equipos de EEG convencionales, por su precio y tamaño, no son una alternativa práctica en quirófanos y los equipos comerciales usados en cirugía no permiten acceder a la actividad eléctrica. Disponer de tecnologías portables y de bajo costo aumentaría el número de investigaciones sobre la actividad cerebral bajo anestesia general y facilitaría la búsqueda de nuevos marcadores para la profundidad anestésica. Objetivo Evaluar la capacidad de una tecnología EEG portable de adquirir ritmos cerebrales relacionados con el estado consciente y el estado de anestesia general de pacientes en cirugía anestesiados con propofol. Métodos Estudio observacional de corte transversal en el que se analizaron datos de 10 registros EEG obtenidos mediante tecnología portable y de bajo costo OpenBCI, de pacientes de sexo femenino que fueron sometidas a anestesia general con propofol. La señal obtenida de los electrodos frontales se analizó mediante análisis espectral y se contrastaron los resultados con lo descrito en la literatura. Resultados La señal obtenida con electrodos frontales, especialmente el ritmo α, permitió diferenciar el reposo con ojos cerrados y ojos abiertos en estado consciente, del estado de mantenimiento de la anestesia durante cirugía. Conclusiones Se logra la diferenciación de estado de reposo y de mantenimiento de la anestesia replicando hallazgos previos de tecnologías convencionales. Estos resultados abren la posibilidad de utilizar las tecnologías portables como el OpenBCI para investigar la dinámica cerebral durante la anestesia.


Subject(s)
Humans , Spectrum Analysis , Technology , Electroencephalography , Anesthesia, General , Brain Mapping , Propofol , Observational Studies as Topic
2.
Neuroscience Bulletin ; (6): 1454-1468, 2021.
Article in English | WPRIM | ID: wpr-922640

ABSTRACT

Visual object recognition in humans and nonhuman primates is achieved by the ventral visual pathway (ventral occipital-temporal cortex, VOTC), which shows a well-documented object domain structure. An on-going question is what type of information is processed in the higher-order VOTC that underlies such observations, with recent evidence suggesting effects of certain visual features. Combining computational vision models, fMRI experiment using a parametric-modulation approach, and natural image statistics of common objects, we depicted the neural distribution of a comprehensive set of visual features in the VOTC, identifying voxel sensitivities with specific feature sets across geometry/shape, Fourier power, and color. The visual feature combination pattern in the VOTC is significantly explained by their relationships to different types of response-action computation (fight-or-flight, navigation, and manipulation), as derived from behavioral ratings and natural image statistics. These results offer a comprehensive visual feature map in the VOTC and a plausible theoretical explanation as a mapping onto different types of downstream response-action systems.


Subject(s)
Animals , Brain Mapping , Humans , Magnetic Resonance Imaging , Occipital Lobe , Pattern Recognition, Visual , Photic Stimulation , Temporal Lobe , Visual Pathways/diagnostic imaging , Visual Perception
3.
Journal of Biomedical Engineering ; (6): 1163-1172, 2021.
Article in Chinese | WPRIM | ID: wpr-921858

ABSTRACT

Entropy model is widely used in epileptic electroencephalogram (EEG) analysis, but there are few reports on how to objectively select the parameters to compute the entropy model in the analysis of resting-state functional magnetic resonance imaging (rfMRI). Therefore, an optimization algorithm to confirm the parameters in multi-scale entropy (MSE) model was proposed, and the location of epileptogenic hemisphere was taken as an example to test the optimization effect by supervised machine learning. The rfMRI data of 20 temporal lobe epilepsy (TLE) patients with hippocampal sclerosis, positive on structural magnetic resonance imaging, were divided into left and right groups. Then, the parameters in MSE model were optimized by the receiver operating characteristic curves (ROC) and area under ROC curve (AUC) values in sensitivity analysis, and the entropy value of the brain regions with statistically significant difference between the groups were taken as sensitive features to epileptogenic hemisphere lateral. The optimized entropy values of these bio-marker brain areas were considered as feature vectors input into the support vector machine (SVM). Finally, combining optimized MSE model with SVM could accurately distinguish epileptogenic hemisphere in TLE at an average accuracy rate of 95%, which was higher than the current level. The results show that the MSE model parameter optimization algorithm can accurately extract the functional imaging markers sensitive to the epileptogenic hemisphere, and achieve the purpose of objectively selecting the parameters for MSE in rfMRI, which provides the basis for the application of entropy in advanced technology detection.


Subject(s)
Brain/diagnostic imaging , Brain Mapping , Entropy , Epilepsy, Temporal Lobe/diagnostic imaging , Humans , Magnetic Resonance Imaging
4.
Chinese Medical Journal ; (24): 2398-2402, 2021.
Article in English | WPRIM | ID: wpr-921130

ABSTRACT

The demand for acquiring different languages has increased with increasing globalization. However, knowledge of the modification of the new language in the neural language network remains insufficient. Although many details of language function have been detected based on the awake intra-operative mapping results, the language neural network of the bilingual or multilingual remains unclear, which raises difficulties in clinical practice to preserve patients' full language ability in neurosurgery. In this review, we present a summary of the current findings regarding the structure of the language network and its evolution as the number of acquired languages increased in glioma patients. We then discuss a new insight into the awake intra-operative mapping protocol to reduce surgical risks during the preservation of language function in multilingual patients with glioma.


Subject(s)
Brain Mapping , Brain Neoplasms/surgery , Glioma/surgery , Humans , Language , Multilingualism
5.
Chinese Acupuncture & Moxibustion ; (12): 1074-1078, 2021.
Article in Chinese | WPRIM | ID: wpr-921012

ABSTRACT

OBJECTIVE@#To investigate the effect of acupuncture on default mode network (DMN) in migraine patients without aura based on functional Magnetic Resonance Imaging (fMRI).@*METHODS@#Fifteen patients with migraine were included and treated with acupuncture based on "root-knot" theory (Zuqiaoyin [GB 44] for @*RESULTS@#Compared before acupuncture, the functional connections of left parahippocampal cortex (PHC) and anterior medial prefrontal cortex (aMPFC), dorsal medial prefrontal cortex (dMPFC) and lateral temporal cortex (LTC) in DMN after acupuncture were weakened (@*CONCLUSION@#Acupuncture shows good clinical efficacy for migraine without aura, and could adjust the functional connection of DMN.


Subject(s)
Acupuncture Therapy , Brain Mapping , Default Mode Network , Humans , Magnetic Resonance Spectroscopy , Migraine Disorders/therapy , Quality of Life
6.
Frontiers of Medicine ; (4): 562-574, 2021.
Article in English | WPRIM | ID: wpr-888749

ABSTRACT

The protection of language function is one of the major challenges of brain surgery. Over the past century, neurosurgeons have attempted to seek the optimal strategy for the preoperative and intraoperative identification of language-related brain regions. Neurosurgeons have investigated the neural mechanism of language, developed neurolinguistics theory, and provided unique evidence to further understand the neural basis of language functions by using intraoperative cortical and subcortical electrical stimulation. With the emergence of modern neuroscience techniques and dramatic advances in language models over the last 25 years, novel language mapping methods have been applied in the neurosurgical practice to help neurosurgeons protect the brain and reduce morbidity. The rapid advancements in brain-computer interface have provided the perfect platform for the combination of neurosurgery and neurolinguistics. In this review, the history of neurolinguistics models, advancements in modern technology, role of neurosurgery in language mapping, and modern language mapping methods (including noninvasive neuroimaging techniques and invasive cortical electroencephalogram) are presented.


Subject(s)
Brain Mapping , Brain Neoplasms , Humans , Language , Neurosurgery , Neurosurgical Procedures
7.
Acta Physiologica Sinica ; (6): 446-458, 2021.
Article in Chinese | WPRIM | ID: wpr-887680

ABSTRACT

The pathogenesis of schizophrenia (SCZ) is not yet clear, and the pathological changes of the brain activity remains debatable. There are still numerous unresolved issues and debates regarding the relationship between functional connection of the brain network and the symptoms of SCZ. In this paper, we provide a comprehensive review of recent research progresses on resting-state and task-based brain networks, which covers the symptoms of SCZ. Furthermore, we discuss the relationship between large-scale brain networks and SCZ symptoms, and propose possible future research directions in the field of SCZ diagnosis and treatment.


Subject(s)
Brain , Brain Mapping , Humans , Magnetic Resonance Imaging , Schizophrenia
8.
Acta Physiologica Sinica ; (6): 355-368, 2021.
Article in Chinese | WPRIM | ID: wpr-887674

ABSTRACT

The disorder of brain-gut interaction is an important cause of irritable bowel syndrome (IBS), but the dynamic characteristics of the brain remain unclear. Since there are many shortcomings for evaluating brain dynamic nature in the previous studies, we proposed a new method based on slope calculation by point-by-point analysis of the data from functional magnetic resonance imaging, and detected the abnormalities of brain dynamic changes in IBS patients. The results showed that compared with healthy subjects, there were dynamic changes in the brain for the IBS patients. After correction by false discovery rate (FDR), significant abnormalities were only found in two functional connections of the right posterior cingulate gyrus linked to left middle frontal gyrus, and the right posterior cingulate gyrus linked to left pallidus. The above results of the brain dynamic analysis were totally different from those of the brain static analysis of IBS patients. Our findings provide novel complementary information for illustrating the central nervous mechanism of IBS and may offer a new direction to explore central target for patients with IBS.


Subject(s)
Brain/diagnostic imaging , Brain Mapping , Gyrus Cinguli/diagnostic imaging , Humans , Irritable Bowel Syndrome/diagnostic imaging , Magnetic Resonance Imaging
9.
Rev. argent. neurocir ; 34(2): 100-115, jun. 2020. ilus
Article in Spanish | LILACS, BINACIS | ID: biblio-1123341

ABSTRACT

Introducción: El lóbulo de la ínsula, o ínsula, se encuentra oculto en la superficie lateral del cerebro. La ínsula está localizada profundamente en el surco lateral o cisura silviana, recubierta por los opérculos frontal, parietal y temporal. Objetivo: Estudiar la compleja anatomía del lóbulo de la ínsula, una de las regiones de mayor complejidad quirúrgica del cerebro humano, y su correlación anatómica con casos quirúrgicos. Material y Métodos: En la primera parte de este estudio presentamos los resultados de nuestras disecciones microquirúrgicas en fotografías 2 D y 3D; en la segunda parte de nuestro trabajo, la correlación anatómica con una serie de 44 cirugías en pacientes con tumores de la ínsula, principalmente gliomas, operados entre 2007 y 2014. Resultados: Extenso conjunto de fibras subcorticales, incluyendo el fascículo uncinado, fronto-occipital inferior y el fascículo arcuato, conectan la ínsula a las regiones vecinas. Varias estructuras anatómicas responsables por déficits neurológicos severos están íntimamente relacionadas con la cirugía de la ínsula, tales como lesiones de la arteria cerebral media, cápsula interna, áreas del lenguaje en el hemisferio dominante y arterias lenticuloestriadas. Conclusión: El entrenamiento en laboratorio de neuroanatomía, estudio de material impreso en 3D, el conocimiento sobre neurofisiología intra-operatoria y el uso de armamento neuroquirúrgico moderno son factores que influencian en los resultados quirúrgicos


Introduction: The insular lobe, or insula, is the cerebral lobe sitting deep in the sylvian fissure and hidden by the lateral surface of the brain. It is covered by the frontal, parietal and temporal operculum. Objectives: To study the anatomy of the insular lobe, one of the most complex parts of the human brain, and to correlate this anatomy with intraoperative findings. Materials and Methods: In the first part of this article we show the results of our dissections, documented in 2D and 3D, and focus on microsurgical anatomy. In the second part we correlate the anatomical structures with intraoperative findings from 44 insular tumor surgeries, mainly gliomas, of patients operated on from 2007 to 2014. Results: Huge bundles of subcortical fibers, like uncinate, inferior fronto-occipital and arcuate fascicles, connect the insula to the neighboring structures. Several anatomical structures related to neurological disabilities are closely related to insular surgery, like the middle cerebral artery, internal capsule, lenticulostriate arteries and cortical and subcortical language circuits. Conclusions: Microsurgical laboratory training, 3D documentation, knowledge of brain mapping and modern neurosurgical armamentarium are important factors in achieving good results with insular glioma tumors.


Subject(s)
Humans , Temporal Lobe , Brain , Brain Mapping , Cerebrum , Anatomy , Neuroanatomy
11.
Chinese Medical Journal ; (24): 344-352, 2020.
Article in English | WPRIM | ID: wpr-877885

ABSTRACT

BACKGROUND@#Resting-state functional magnetic resonance imaging (rs-fMRI) is a promising method for the study of brain function. Typically, rs-fMRI is performed on anesthetized animals. Although different functional connectivity (FC) in various anesthetics on whole brain have been studied, few studies have focused on different FC in the aged brain. Here, we measured FC under three commonly used anesthesia methods and analyzed data to determine if the FC in whole brain analysis were similar among groups.@*METHODS@#Twenty-four male aged Wistar rats were randomly divided into three groups (n = 8 in each group). Anesthesia was performed under either isoflurane (ISO), combined ISO + dexmedetomidine (DEX) or α-chloralose (AC) according to the groups. Data of rs-fMRI was analyzed by FC in a voxel-wise way. Differences in the FC maps between the groups were analyzed by one-way analysis of variance and post hoc two-sample t tests.@*RESULTS@#Compared with ISO + DEX anesthesia, ISO anesthesia caused increased FC in posterior brain and decreased FC in the middle brain of the aged rat. AC anesthesia caused global suppression as no increase in FC was observed.@*CONCLUSION@#ISO could be used as a substitute for ISO + DEX in rat default mode network studies if the left temporal association cortex is not considered important.


Subject(s)
Anesthesia , Animals , Brain/diagnostic imaging , Brain Mapping , Isoflurane , Magnetic Resonance Imaging , Male , Rats , Rats, Wistar
12.
Article in Chinese | WPRIM | ID: wpr-828121

ABSTRACT

How to extract high discriminative features that help classification from complex resting-state fMRI (rs-fMRI) data is the key to improving the accuracy of brain disease recognition such as schizophrenia. In this work, we use a weighted sparse model for brain network construction, and utilize the Kendall correlation coefficient (KCC) to extract the discriminative connectivity features for schizophrenia classification, which is conducted with the linear support vector machine. Experimental results based on the rs-fMRI of 57 schizophrenia patients and 64 healthy controls show that our proposed method is more effective ( ., achieving a significantly higher classification accuracy, 81.82%) than other competing methods. Specifically, compared with the traditional network construction methods (Pearson's correlation and sparse representation) and the commonly used feature selection methods (two-sample -test and Least absolute shrinkage and selection operator (Lasso)), the algorithm proposed in this paper can more effectively extract the discriminative connectivity features between the schizophrenia patients and the healthy controls, and further improve the classification accuracy. At the same time, the discriminative connectivity features extracted in the work could be used as the potential clinical biomarkers to assist the identification of schizophrenia.


Subject(s)
Algorithms , Brain , Brain Mapping , Humans , Magnetic Resonance Imaging , Schizophrenia , Diagnostic Imaging
13.
Frontiers of Medicine ; (4): 792-801, 2020.
Article in English | WPRIM | ID: wpr-880935

ABSTRACT

Asthma is a serious health problem that involves not only the respiratory system but also the central nervous system. Previous studies identified either regional or network alterations in patients with asthma, but inconsistent results were obtained. A key question remains unclear: are the regional and neural network deficits related or are they two independent characteristics in asthma? Answering this question is the aim of this study. By collecting resting-state functional magnetic resonance imaging from 39 patients with asthma and 40 matched health controls, brain functional measures including regional activity (amplitude of low-frequency fluctuations) and neural network function (degree centrality (DC) and functional connectivity) were calculated to systematically characterize the functional alterations. Patients exhibited regional abnormities in the left angular gyrus, right precuneus, and inferior temporal gyrus within the default mode network. Network abnormalities involved both the sensorimotor network and visual network with key regions including the superior frontal gyrus and occipital lobes. Altered DC in the lingual gyrus was correlated with the degree of airway obstruction. This study elucidated different patterns of regional and network changes, thereby suggesting that the two parameters reflect different brain characteristics of asthma. These findings provide evidence for further understanding the potential cerebral alterations in the pathophysiology of asthma.


Subject(s)
Asthma/diagnostic imaging , Brain/diagnostic imaging , Brain Mapping , Humans , Magnetic Resonance Imaging
14.
Journal of Biomedical Engineering ; (6): 1089-1094, 2020.
Article in Chinese | WPRIM | ID: wpr-879240

ABSTRACT

Hemispheric asymmetry is a fundamental organizing principle of the human brain. Answering the genetic effects of the asymmetry is a prerequisite for elucidating developmental mechanisms of brain asymmetries. Multi-modal magnetic resonance imaging (MRI) has provided an important tool for comprehensively interpreting human brain asymmetry and its genetic mechanism. By combining MRI data, individual differences in brain structural asymmetry have been investigated with quantitative genetic brain mapping using gene-heritability. Twins provide a useful natural model for studying the effects of genetics and environment on the brain. Studies based on MRI have found that the asymmetry of human brain structure has a genetic basis. From the perspective of quantitative genetic analysis, this article reviews recent findings on the genetic effects of asymmetry and genetic covariance between hemispheres from three aspects: the asymmetry of heritability, the heritability of asymmetry and the genetic correlation. At last, the article shows the limitations and future research directions in this field. The purpose of this systematic review is to quickly guide researchers to understand the origins and genetic mechanism of interhemispheric differences, and provide a genetic basis for further understanding and exploring individual differences in laterized cognitive behavior.


Subject(s)
Brain/diagnostic imaging , Brain Mapping , Humans , Magnetic Resonance Imaging , Twins/genetics
15.
Article in Chinese | WPRIM | ID: wpr-879201

ABSTRACT

Aiming at the difference between the brain networks of children with attention deficit hyperactivity disorder (ADHD) and normal children in the task-executing state, this paper conducted a comparative study using the network features of the visual function area. Functional magnetic resonance imaging (fMRI) data of 23 children with ADHD [age: (8.27 ± 2.77) years] and 23 normal children [age: (8.70 ± 2.58) years] were obtained by the visual capture paradigm when the subjects were performing the guessing task. First, fMRI data were used to build a visual area brain function network. Then, the visual area brain function network characteristic indicators including degree distribution, average shortest path, network density, aggregation coefficient, intermediary, etc. were obtained and compared with the traditional whole brain network. Finally, support vector machines (SVM) and other classifiers in the machine learning algorithm were used to classify the feature indicators to distinguish ADHD children from normal children. In this study, visual brain function network features were used for classification, with a classification accuracy of up to 96%. Compared with the traditional method of constructing a whole brain network, the accuracy was improved by about 10%. The test results show that the use of visual area brain function network analysis can better distinguish ADHD children from normal children. This method has certain help to distinguish the brain network between ADHD children and normal children, and is helpful for the auxiliary diagnosis of ADHD children.


Subject(s)
Attention Deficit Disorder with Hyperactivity/diagnostic imaging , Brain/diagnostic imaging , Brain Mapping , Child , Child, Preschool , Cognition , Humans , Magnetic Resonance Imaging
16.
Arq. neuropsiquiatr ; 77(11): 797-805, Nov. 2019. tab, graf
Article in English | LILACS | ID: biblio-1055187

ABSTRACT

ABSTRACT Drug-resistant epilepsy associated with central nervous system tumors is generally caused by low grade gliomas. This group of tumors is usually found in brain eloquent areas, such as the insular lobe, rolandic cortex and supplementary motor area and, historically, possess a greater risk of postoperative deficits. Objective: The aim of this investigation was to present our surgical experience on patients with drug-resistant epilepsy caused by gliomas in eloquent areas. We retrospectively investigated variables that impact seizure control, such as tumor location, extent of resection, invasion into the lenticulostriate arteries in the patient, especially those with insular gliomas. Methods: Out of 67 patients with eloquent area brain tumors operated on in our service between 2007 and 2016, 14 patients had symptoms of drug-resistant epilepsy. Volumetric analysis, extent of resection (EOR), type of approach and mapping, among other factors were correlated with the 12-month postoperative seizure outcome. Results: Univariate analysis showed that the factors showing statistical relevance with seizure control were preoperative volume (p = 0.005), EOR (p = 0.028) and postoperative volume (p = 0.030). Conclusion: There was a statistically significant association between the EOR and the Engel score for epilepsy control: an EOR < 70 was associated with Engel II, III, IV and an EOR > 90 was associated with Engel I. Eloquent area gliomas can safely be resected when surgeons use not only microsurgical anatomy concepts but also brain mapping.


RESUMO Epilepsia refratária secundária a tumores cerebrais são geralmente causadas por gliomas de baixo grau. Esse grupo de tumor é frequentemente localizado em áreas eloquentes do cérebro como na insula, córtex rolândico e área motora suplementar; e sua ressecção apresenta alto risco de déficits neurológicos no pós operatório. Objetivo: O objetivo do estudo consiste em apresentar nossa experiência no tratamento cirúrgico de pacientes com epilepsia refratária secundário a gliomas em áreas eloquentes. Métodos: O estudo consiste em investigação retrospectiva de variáveis que interferem no controle de crises, tais como localização do tumor, grau de ressecção, invasão tumoral de artérias lenticulo estriadas, principalmente em gliomas insulares. Dentre 67 pacientes portadores de gliomas em área eloquente operados no período de 2007 a 2016, 14 doentes apresentavam epilepsia refrataria associada. Análise volumétrica do tumor, grau de ressecção, acesso cirúrgico, bem como o uso de mapeamento cortical intraoperatório foram correlacionados com desfecho de controle de crises epilepticas em 12 meses. Resultados: Em análise univariada os fatores relacionados com controle de crises em 12 meses foram volume tumoral pré operatório (p = 0,005), grau de ressecção (p = 0,028) e volume tumoral pós operatório. Conclusão: O grau de ressecção apresentou significância estatística em relação ao controle de crises conforme escala de Engel. Ressecções menores que 70% apresentaram correlação com Engel II, III e IV; enquanto ressecções maiores que 90% apresentaram correção positiva com Engel I. Gliomas em áreas eloquentes podem ser ressecados de forma segura desde que seja realizada por equipe experiente com conhecimento acurado da anatomia microcirúrgica e emprego de mapeamento cortical intraoperatório.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Brain Neoplasms/surgery , Brain Neoplasms/complications , Brain Neoplasms/etiology , Drug Resistant Epilepsy/surgery , Glioma/surgery , Glioma/complications , Postoperative Period , Seizures/surgery , Seizures/etiology , Brain Mapping , Brain Neoplasms/mortality , Brain Neoplasms/diagnostic imaging , Magnetic Resonance Imaging , Reproducibility of Results , Retrospective Studies , Risk Factors , Treatment Outcome , Statistics, Nonparametric , Kaplan-Meier Estimate , Glioma/mortality , Glioma/diagnostic imaging
17.
Braz. j. med. biol. res ; 52(5): e8244, 2019. tab, graf
Article in English | LILACS | ID: biblio-1001520

ABSTRACT

This study aimed to explore the structural and functional characteristics of the neural network of resting-state brain activities in patients with amnestic mild cognitive impairment (aMCI) by functional magnetic resonance imaging (fMRI) technology. Resting state fMRI scanning was performed on 10 clinically diagnosed aMCI patients and 10 healthy volunteers, and the difference in the resting-state brain activities between aMCI patients and healthy volunteers was compared using the brain function network regional homogeneity (ReHo) analysis method. Results of the ReHo analysis of aMCI patients and healthy volunteers revealed that the ReHo value significantly increased in the posterior cingulate gyrus region, medial frontal lobe, medial cortex of the prefrontal lobe, and part of the parietal lobe. Compared with the normal elderlies, ReHo decreased in aMCI patients in the left temporal lobe (middle temporal gyrus and inferior temporal gyrus), left parahippocampal gyrus, occipital lobe, lingual gyrus, precuneus, and other regions while ReHo increased in regions of the right frontal lobe (inferior frontal gyrus), left superior temporal gyrus, precentral gyrus (frontal lobe), right thalamus, left fusiform gyrus, and other regions. In the resting state, there may be regional abnormalities in brain functional areas in aMCI patients, which may be associated with cognitive impairment.


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Brain/physiology , Cognitive Dysfunction/physiopathology , Image Processing, Computer-Assisted , Brain/diagnostic imaging , Brain Mapping , Magnetic Resonance Imaging , Cognitive Dysfunction/diagnostic imaging , Neural Pathways/physiopathology
18.
Clinics ; 74: e908, 2019. tab, graf
Article in English | LILACS | ID: biblio-1011907

ABSTRACT

OBJECTIVES: Approximately one-third of candidates for epilepsy surgery have no visible abnormalities on conventional magnetic resonance imaging. This is extremely discouraging, as these patients have a less favorable prognosis. We aimed to evaluate the utility of quantitative magnetic resonance imaging in patients with drug-resistant neocortical focal epilepsy and negative imaging. METHODS: A prospective study including 46 patients evaluated through individualized postprocessing of five quantitative measures: cortical thickness, white and gray matter junction signal, relaxation rate, magnetization transfer ratio, and mean diffusivity. Scalp video-electroencephalography was used to suggest the epileptogenic zone. A volumetric fluid-attenuated inversion recovery sequence was performed to aid visual inspection. A critical assessment of follow-up was also conducted throughout the study. RESULTS: In the subgroup classified as having an epileptogenic zone, individualized postprocessing detected abnormalities within the region of electroclinical origin in 9.7% to 31.0% of patients. Abnormalities outside the epileptogenic zone were more frequent, up to 51.7%. In five patients initially included with negative imaging, an epileptogenic structural abnormality was identified when a new visual magnetic resonance imaging inspection was guided by information gleaned from postprocessing. In three patients, epileptogenic lesions were detected after visual evaluation with volumetric fluid-attenuated sequence guided by video electroencephalography. CONCLUSION: Although quantitative magnetic resonance imaging analyses may suggest hidden structural lesions, caution is warranted because of the apparent low specificity of these findings for the epileptogenic zone. Conversely, these methods can be used to prevent visible lesions from being ignored, even in referral centers. In parallel, we need to highlight the positive contribution of the volumetric fluid-attenuated sequence.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Young Adult , Magnetic Resonance Imaging/methods , Drug Resistant Epilepsy/diagnostic imaging , Brain Mapping , Prospective Studies , Diagnosis, Computer-Assisted/methods , Electroencephalography/methods , Multimodal Imaging
19.
Acta Physiologica Sinica ; (6): 760-768, 2019.
Article in Chinese | WPRIM | ID: wpr-777134

ABSTRACT

Obstructive sleep apnea (OSA) is a common clinic sleep disorder, and characterized by obstruction of upper airway during sleep, resulting in sleep fragmentation and intermittent hypoxemia. We reviewed the brain imaging studies in OSA patients compared with healthy subjects, including studies of functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). The resting-state EEG studies showed increased power of δ and θ in the front and central regions of the cerebral cortex in OSA patients. While resting-state fMRI studies demonstrated altered large-scale networks in default-mode network (DMN), central executive network (CEN) and salience network (SN). Evidence from resting-state studies of both fMRI and EEG focused on the abnormal activity in prefrontal cortex (PFC), which is correlated with OSA severity. These findings suggested that the PFC may play a key role in the abnormal function of OSA patients. Finally, based on the perspectives of treatment effect, multimodal data acquisition, and comorbidities, we discussed the future research direction of the neuroimaging study of OSA.


Subject(s)
Brain , Diagnostic Imaging , Brain Mapping , Electroencephalography , Humans , Magnetic Resonance Imaging , Sleep Apnea, Obstructive , Diagnostic Imaging
20.
Acta Physiologica Sinica ; (6): 73-85, 2019.
Article in Chinese | WPRIM | ID: wpr-777208

ABSTRACT

The purpose of the present paper was to review the processing mechanisms of social cues in faces. We summarized researches relative to social cues in faces and discussed the processing mechanism of these cues from the aspects of facial expression, facial attractiveness, gaze and face direction, and lipreading. First, we discussed the general neural mechanism of face information processing and summarized the functions of face areas in the fusiform gyrus, posterior superior temporal sulcus and inferior occipital gyrus. Next, the neural mechanism of emotional face perception was discussed. The processing of emotional faces consists of encodings of perceptual and emotional components. The amygdala plays an important role in the emotional processing of facial expressions. Furthermore, the neural responses to facial expressions may be influenced by multiple factors, such as the type of emotion, the dynamic presentation of the face and the consciousness of facial expressions. With respect to facial attractiveness processing, studies has shown that the reward circuitry is activated by highly attractive faces. However, the influence of facial attractiveness on neural responses remains elusive. It is proposed that the neural responses to facial attractiveness might be modulated by factors such as the task, observer's sex, expectation and other social cues in faces. Eye gaze perception and face view perception are related to visual attention, and the relevant neural circuitry has been found to include attention-related areas, such as the intraparietal sulcus. Finally, research on lipreading reveals its important role in language perception. The auditory cortex and language-related cortex have been shown to be activated by lipreading. In summary, the present evidence may support facial information processing theory. However, the theory could be further improved based on present and future findings. Furthermore, we discussed the deficits in the processing of social cues in individuals with mental disorders and proposed future research directions in this field.


Subject(s)
Brain Mapping , Cues , Emotions , Facial Expression , Humans , Magnetic Resonance Imaging , Temporal Lobe , Physiology
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