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1.
J Affect Disord ; 329: 225-234, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36858265

RESUMO

BACKGROUND: A recent study revealed disrupted topological organization of whole-brain networks in patients with major depressive disorder (MDD); however, these results were mostly driven by recurrent MDD patients, rather than first-episode drug-naïve (FEDN) patients. Furthermore, few longitudinal studies have explored the effects of antidepressant therapy on the topological organization of whole-brain networks. METHODS: We collected clinical and neuroimaging data from 159 FEDN MDD patients and 152 normal controls (NCs). A total of 115 MDD patients completed an eight-week antidepressant treatment procedure. Topological features of brain networks were calculated using graph theory-based methods and compared between FEDN MDD patients and NCs, as well as before and after treatment. RESULTS: Decreased global efficiency, local efficiency, small-worldness, and modularity were found in pretreatment FEDN MDD patients compared with NCs. Nodal degrees, betweenness, and efficiency decreased in several networks compared with NCs. After antidepressant treatment, the global efficiency increased, while the local efficiency, the clustering coefficient of the network, the path length, and the normalized characteristic path length decreased. Moreover, the reduction rate of the normalized characteristic path length was positively correlated with the reduction rate of retardation factor scores. LIMITATIONS: The interaction effects of groups and time on the topological features were not explored because of absence of the eighth-week data of NC group. CONCLUSIONS: The topological architecture of functional brain networks is disrupted in FEDN MDD patients. After antidepressant therapy, the global efficiency shifted toward recovery, but the local efficiency deteriorated, suggesting a correlation between recovery of retardation symptoms and global efficiency.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Antidepressivos/uso terapêutico
2.
Int J Eat Disord ; 56(7): 1353-1364, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36951235

RESUMO

OBJECTIVE: Bulimia nervosa (BN) is an eating disorder associated with the dysfunction of intrinsic brain networks. However, whether the network disruptions in BN patients manifest as dysconnectivity or imbalances of network modular segregation remains unclear. METHOD: We collected data from 41 women with BN and 41 matched healthy control (HC) women. We performed graph theory analysis based on resting-state functional magnetic resonance imaging (RS-fMRI) data; then, we computed the participation coefficient (PC) among brain modules to characterize the modular segregation for the BN and HC groups. The number of intra- and inter-modular connections was calculated to explain the PC changes. Additionally, we examined the potential associations of the measures mentioned above with clinical variables within the BN group. RESULTS: Compared with the HC group, the BN group showed significantly decreased PC in the fronto-parietal network (FPN), cingulo-opercular network (CON), and cerebellum (Cere). Additionally, the number of intra-modular connections of the default mode network (DMN) and the number of the inter-modular connections between the DMN and CON, FPN and Cere, and CON and Cere in the BN group were lower than those in the HC group. The nodal level analysis showed that the BN group had a decreased PC of the anterior prefrontal cortex (aPFC), dorsal frontal cortex (dFC), inferior parietal lobule (IPL), thalamus, and angular gyrus. Further, these metrics were significantly correlated with clinical variables in the BN group. DISCUSSION: These findings may provide novel insights to capture atypical topologies associated with pathophysiology mechanisms and clinical symptoms underlying BN.


Assuntos
Bulimia Nervosa , Transtornos da Alimentação e da Ingestão de Alimentos , Humanos , Feminino , Bulimia Nervosa/diagnóstico por imagem , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Córtex Pré-Frontal , Mapeamento Encefálico
3.
Psych J ; 8(2): 261-270, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30520271

RESUMO

Prospective memory (PM) refers to the ability to remember to do something in the future. Implementation intention refers to a self-regulatory strategy in the form of "If …, then …" planning that can improve PM performance. However, the neural basis of the effect of implementation intention on PM remains unclear, as do the phases of PM that are affected by implementation intention. This study aimed to address these issues. Healthy participants were randomly assigned to the implementation intention (n = 18) and typical instruction (n = 20) conditions. All of them underwent functional magnetic resonance imaging (fMRI) scanning when performing a PM task, which differentiated encoding, maintenance, and execution phases. Results demonstrated that participants in the implementation intention group showed different brain activations compared to participants in the typical instruction group. During the encoding phase, the implementation intention group showed increased activations in the inferior frontal gyrus (BA 10) and supramarginal gyrus (BA 40) compared to the typical instruction group; during the maintenance phase, the typical instruction group showed stronger activations in the inferior frontal gyrus (BA 46) than the implementation intention group; during the execution phase, the typical instruction group showed increased activations in the precentral gyrus (BA 6) and middle frontal gyrus (BA 8) than the implementation intention group. These results demonstrated the neural correlates of implementation intention on PM in different phases, and support the conclusion of our previous review based on fMRI evidence that implementation intention's improvement of PM performance is not fully automatic.


Assuntos
Intenção , Memória Episódica , Vias Neurais/fisiopatologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Adulto , China , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
4.
Neuropsychology ; 32(6): 764-776, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30047755

RESUMO

OBJECTIVE: Impaired nucleus accumbens (NAcc) activation is associated with amotivation and anhedonia, which are resistant to treatment with antipsychotics and antidepressants in schizophrenia. In this study, healthy participants were trained to self-regulate the activation of their NAcc, a brain region that plays an important role in motivation, using real-time functional magnetic resonance imaging (fMRI) neurofeedback. METHOD: The experimental group (N = 19) received feedback from the NAcc, whereas the control group (N = 5) received "sham" feedback from the posterior parahippocampal gyrus, a control brain region not normally related to motivation. All participants were trained to use mental strategies to regulate their NAcc activations in a 3T MRI scanner. RESULTS: For the learning effect of NAcc regulation, we found that the majority of participants (74%) in the experimental group successfully learned to self-regulate the NAcc. They also showed improved behavioral performance in motivation and decreased functional connectivity between the NAcc and the ventral medial prefrontal cortex and an increase in small-world properties in the reward circuit after training, indicating improved information integration in reward processing. However, improvement in motivation and modification of function connectivity were not observed in the sham control group and the participants who failed to self-regulate the NAcc in the experimental group. Self-regulation was influenced by the baseline motivation. CONCLUSIONS: These findings suggest that the NAcc could be self-regulated using real-time fMRI neurofeedback and can result in improved motivation in cognitive tasks. (PsycINFO Database Record


Assuntos
Neuroimagem Funcional/métodos , Motivação/fisiologia , Neurorretroalimentação/fisiologia , Núcleo Accumbens/fisiologia , Autocontrole , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Núcleo Accumbens/diagnóstico por imagem
5.
Neuropsychology ; 32(3): 329-336, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29620404

RESUMO

OBJECTIVE: The present study aimed to investigate the neural basis of information matching during sensory integration using a spatial-temporal matching task in healthy individuals. METHOD: A total of 37 healthy participants were recruited to match spatial dots with an auditory tone sequence in a 3T GE Discovery MR750 scanner. In addition, they were examined with the sensory integration subscale of the Cambridge Neurological Inventory. RESULTS: We found that the bilateral occipital-parietal conjunction cortex and the precentral frontal gyrus were activated during the matching condition rather than in the nonmatching condition. Activation of the occipital-parietal conjunction cortex was associated with integration of information across visual and auditory modalities, whereas activation of the precentral frontal gyrus was associated with decision making of movements. In addition, activation of the left superior frontal gyrus was associated with scores on the sensory integration subscale of the Cambridge Neurological Inventory. CONCLUSIONS: These findings suggest that the bilateral occipital-parietal conjunction cortex is responsible for matching information input from multiple modalities during audiovisual sensory integration. (PsycINFO Database Record


Assuntos
Percepção Auditiva/fisiologia , Sensação/fisiologia , Percepção Visual/fisiologia , Adolescente , Tomada de Decisões/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Processos Mentais/fisiologia , Movimento/fisiologia , Testes Neuropsicológicos , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/fisiologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Adulto Jovem
6.
Hum Brain Mapp ; 39(3): 1438-1448, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29266498

RESUMO

Complex motor sequencing and sensory integration are two key items in scales assessing neurological soft signs. However, the underlying neural mechanism and heritability of these two functions is not known. Using a healthy twin design, we adopted two functional brain imaging tasks focusing on fist-edge-palm (FEP) complex motor sequence and audiovisual integration (AVI). Fifty-six monozygotic twins and 56 dizygotic twins were recruited in this study. The pre- and postcentral, temporal and parietal gyri, the supplementary motor area, and the cerebellum were activated during the FEP motor sequence, whereas the precentral, temporal, and fusiform gyri, the thalamus, and the caudate were activated during AVI. Activation in the supplementary motor area during FEP motor sequence and activation in the precentral gyrus and the thalamic nuclei during AVI exhibited significant heritability estimates, ranging from 0.5 to 0.62. These results suggest that activation in cortical motor areas, the thalamus and the cerebellum associated with complex motor sequencing and audiovisual integration function may be heritable.


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Destreza Motora/fisiologia , Percepção Visual/fisiologia , Adolescente , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Humanos , Padrões de Herança , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia , Gêmeos Dizigóticos , Gêmeos Monozigóticos , Adulto Jovem
7.
J Psychiatry Neurosci ; 42(6): 414-423, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28949286

RESUMO

BACKGROUND: Bulimia nervosa is a severe psychiatric syndrome with uncertain pathogenesis. Neural systems involved in sensorimotor and visual processing, reward and impulsive control may contribute to the binge eating and purging behaviours characterizing bulimia nervosa. However, little is known about the alterations of functional organization of whole brain networks in individuals with this disorder. METHODS: We used resting-state functional MRI and graph theory to characterize functional brain networks of unmedicated women with bulimia nervosa and healthy women. RESULTS: We included 44 unmedicated women with bulimia nervosa and 44 healthy women in our analyses. Women with bulimia nervosa showed increased clustering coefficient and path length compared with control women. The nodal strength in patients with the disorder was higher in the sensorimotor and visual regions as well as the precuneus, but lower in several subcortical regions, such as the hippocampus, parahippocampal gyrus and orbitofrontal cortex. Patients also showed hyperconnectivity primarily involving sensorimotor and unimodal visual association regions, but hypoconnectivity involving subcortical (striatum, thalamus), limbic (amygdala, hippocampus) and paralimbic (orbitofrontal cortex, parahippocampal gyrus) regions. The topological aberrations correlated significantly with scores of bulimia and drive for thinness and with body mass index. LIMITATIONS: We reruited patients with only acute bulimia nervosa, so it is unclear whether the topological abnormalities comprise vulnerability markers for the disorder developing or the changes associated with illness state. CONCLUSION: Our findings show altered intrinsic functional brain architecture, specifically abnormal global and local efficiency, as well as nodal- and network-level connectivity across sensorimotor, visual, subcortical and limbic systems in women with bulimia nervosa, suggesting that it is a disorder of dysfunctional integration among large-scale distributed brain regions. These abnormalities contribute to more comprehensive understanding of the neural mechanism underlying pathological eating and body perception in women with bulimia nervosa.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Bulimia Nervosa/diagnóstico por imagem , Bulimia Nervosa/fisiopatologia , Conectoma , Feminino , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Descanso , Adulto Jovem
8.
Sci Rep ; 6: 35481, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27752140

RESUMO

Anhedonia, the diminished ability to experience pleasure, is a challenging negative symptom in patients with schizophrenia and can be observed in at-risk individuals with schizotypy. Deficits in hedonic processing have been postulated to be related to decreased motivation to engage in potentially rewarding events. It remains unclear whether non-pharmacological interventions, such as cognitive training, could improve anhedonia. The present study aimed to examine the neural mechanism for alleviating hedonic deficits with working memory (WM) training in individuals with social anhedonia. Fifteen individuals with social anhedonia were recruited and received 20 sessions of training on a dual n-back task, five sessions a week. Functional imaging paradigms of the Monetary Incentive Delay (MID) and the Affective Incentive Delay (AID) tasks were administered both before and after the training to evaluate the neural transfer effects on hedonic processing ability. Enhanced brain activations related to anticipation were observed at the anterior cingulate cortex, the left dorsal striatum and the left precuneus with the AID task, and at the dorsolateral prefrontal cortex and the supramarginal gyrus with the MID task. The present findings support that WM training may improve monetary-based and affective-based hedonic processing in individuals with social anhedonia.


Assuntos
Anedonia , Memória de Curto Prazo , Encéfalo/fisiopatologia , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Aprendizagem , Imageamento por Ressonância Magnética , Masculino , Psicologia do Esquizofrênico , Comportamento Social , Estudantes
9.
Neuropsychology ; 30(3): 274-80, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26280299

RESUMO

OBJECTIVE: Anticipatory and consummatory dissociation of hedonic experience may manifest as trait anhedonia in healthy and clinical populations. It is still unclear whether the underlying neural mechanisms of the monetary-based and affect-based incentive delay paradigms are distinct from each other. The present study aimed to examine the similarities and differences between the Affect Incentive Delay (AID) and the Monetary Incentive Delay (MID) imaging paradigms in relation to brain activations. METHOD: We administered the AID and the MID imaging tasks to 28 adolescent participants. A cue signaling the type of forthcoming feedback (reward or punishment) was displayed to the participants, followed by a target-hit task with corresponding reward or punishment. RESULTS: The striatal and limbic regions were activated during the anticipatory phase of MID, while there was no brain activation during the anticipatory phase of AID. In the consummatory phase, the MID task activated the medial frontal cortex, while the AID task activated the frontal and dorsal limbic regions. We further found that the anhedonic group exhibited significant hypoactivation than the nonanhedonic group at the left pulvinar, the left claustrum and the left insula to positive cues in the anticipatory phase of the AID task. CONCLUSIONS: The results suggest that the AID and the MID tasks have unique activation patterns. Our findings also suggest that the AID task may be more sensitive in detecting anhedonia in people with trait anhedonia.


Assuntos
Anedonia , Recompensa , Meio Social , Adolescente , Antecipação Psicológica , Sinais (Psicologia) , Retroalimentação Psicológica , Feminino , Lobo Frontal/fisiologia , Humanos , Sistema Límbico , Masculino , Motivação , Neostriado , Testes Neuropsicológicos , Prazer , Punição , Adulto Jovem
10.
BMC Psychiatry ; 15: 298, 2015 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-26590556

RESUMO

BACKGROUND: The clinical presentation of common symptoms during depressive episodes in bipolar disorder (BD) and major depressive disorder (MDD) poses challenges for accurate diagnosis. Disorder-specific neuroanatomical features may aid the development of reliable discrimination between these two clinical conditions. METHODS: For our sample of 16 BD patients, 19 MDD patients and 29 healthy volunteers, we adopted vertex-wise cortical based brain imaging techniques to examine cortical thickness and surface area, two components of cortical volume with distinct genetic determinants. Based on specific characteristics of neuroanatomical features, we then used support vector machine (SVM) algorithm to discriminate between patients with BD and MDD. RESULTS: Compared to MDD patients, BD patients showed significantly larger cortical surface area in the left bankssts, precuneus, precentral, inferior parietal, superior parietal and the right middle temporal gyri. In addition, larger volumes of subcortical regions were found in BD patients. In SVM discriminative analyses, the overall accuracy was 74.3 %, with a sensitivity of 62.5 % and a specificity of 84.2 % (p = 0.028). Compared to controls, larger surface area in the temporo-parietal regions were observed in BD patients, and thinner cortices in fronto-temporal regions were observed in MDD patients, especially in the medial orbito-frontal area. CONCLUSIONS: These findings have demonstrated distinct spatially distributed variations in cortical thickness and surface area in patients with BD and MDD, suggesting potentially varying etiological and neuropathological processes in these two conditions. The employment of multimodal classification on disorder-specific biological features has shed light to the development of potential classification tools that could aid diagnostic decisions.


Assuntos
Transtorno Bipolar/patologia , Córtex Cerebral/patologia , Transtorno Depressivo Maior/patologia , Adulto , Antipsicóticos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Transtorno Depressivo Maior/tratamento farmacológico , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Projetos Piloto
11.
Front Behav Neurosci ; 9: 217, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26321934

RESUMO

Convergent evidence suggests the important role of the mesolimbic pathway in anticipating monetary rewards. However, the underlying mechanism of how the sub-regions interact with each other is still not clearly understood. Using dynamic causal modeling, we constructed a reward-related network for anticipating monetary reward using the Monetary Incentive Delay Task. Twenty-six healthy adolescents (Female/Male = 11/15; age = 18.69 ± 1.35 years; education = 12 ± 1.58 years) participated in the present study. The best-fit network involved the right substantia nigra/ventral tegmental area (SN/VTA), the right nucleus accumbens (NAcc) and the right thalamus, which were all activated during anticipation of monetary gain and loss. The SN/VTA directly activates the NAcc and the thalamus. More importantly, monetary gain modulated the connectivity from the SN/VTA to the NAcc and this was significantly correlated with subjective anticipatory pleasure (r = 0.649, p < 0.001). Our findings suggest that activity in the mesolimbic pathway during the anticipation of monetary reward could to some extent be predicted by subjective anticipatory pleasure.

12.
Medicine (Baltimore) ; 94(37): e1550, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26376406

RESUMO

Decreased intelligence quotients (IQ) have been consistently reported in drug-naive benign childhood epilepsy with centrotemporal spikes (BECTS). We aimed to identify the neurophysiological basis of IQ deficits by studying interhemispheric and anatomical functional connectivity in BECTS patients. Resting-state functional and structural magnetic resonance images were acquired in 32 children with BECTS and 25 healthy controls. The IQ was estimated using Wechsler Intelligence Scale for Children China-Revised. The functional connectivity between bilateral homotopic voxels was calculated and compared between groups. Homotopic regions showing abnormal functional connectivity in patients were adopted as regions of interest for analysis by diffusion-tensor imaging tractography. The fractional anisotropy, fiber length, and fiber number were compared between groups. Abnormal homotopic connectivities were correlated with IQ in BECTS patients. Compared with control subjects, patients showed decreased IQ, and decreased voxel-mirrored homotopic connectivity (VMHC) in the bilateral frontal lobule and cerebellum. The performance and full scale IQ significantly increased with the VMHC strength of the middle frontal gyrus (MFG) in controls but not in BECTS patients. A significant negative correlation was observed between VMHC in the premotor cortex and disease duration. Microstructural features within white matter tracts connecting functionally abnormal regions did not reveal any differences between groups. This study provides preliminary evidence for the disrupted functional cooperation between hemispheres in children with BECTS. The findings suggest that the hyposynchrony between the bilateral MFG may be involved in the decreased IQ of BECTS patients.


Assuntos
Epilepsia Rolândica/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Adolescente , Estudos de Casos e Controles , Criança , Imagem de Difusão por Ressonância Magnética , Epilepsia Rolândica/psicologia , Feminino , Humanos , Masculino , Escalas de Wechsler
13.
PLoS One ; 10(7): e0134361, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26225427

RESUMO

The aim of the current study was to localize the epileptic focus and characterize its causal relation with other brain regions, to understand the cognitive deficits in children with benign childhood epilepsy with centrotemporal spikes (BECTS). Resting-state functional magnetic resonance imaging (fMRI) was performed in 37 children with BECTS and 25 children matched for age, sex and educational achievement. We identified the potential epileptogenic zone (EZ) by comparing the amplitude of low frequency fluctuation (ALFF) of spontaneous blood oxygenation level dependent fMRI signals between the groups. Granger causality analysis was applied to explore the causal effect between EZ and the whole brain. Compared with controls, children with BECTS had significantly increased ALFF in the right postcentral gyrus and bilateral calcarine, and decreased ALFF in the left anterior cingulate cortex, bilateral putaman/caudate, and left cerebellum. ALFF values in the putaman/caudate were positively correlated with verbal IQ scores in patients. The ALFF values in cerebellum and performance IQ scores were negatively correlated in patients. These results suggest that ALFF disturbances in the putaman/caudate and cerebellum play an important role in BECTS cognitive dysfunction. Compared with controls, the patients showed increased driving effect from the EZ to the right medial frontal cortex and posterior cingulate cortex and decreased causal effects from the EZ to left inferior frontal gyrus. The causal effect of the left inferior frontal gyrus negatively correlated with disease duration, which suggests a relation between the epileptiform activity and language impairment. All together, these findings provide additional insight into the neurophysiological mechanisms of epilepitogenisis and cognitive dysfunction associated with BECTS.


Assuntos
Potenciais de Ação , Epilepsia/fisiopatologia , Adolescente , Estudos de Casos e Controles , Criança , Humanos , Imageamento por Ressonância Magnética , Testes Neuropsicológicos
14.
Neuropsychology ; 28(3): 373-81, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24219614

RESUMO

OBJECTIVE: Prospective memory (PM) refers to the ability to remember to perform actions in the future. Schizophrenia spectrum disorders show impairments in PM but neural correlates of these impairments remain unclear. The present study aimed to examine brain activation during PM to identify impairments in individuals with schizotypal personality features. METHOD: Nineteen participants with schizotypal features and 22 healthy controls participated in a functional MRI experiment while performing a PM task. RESULTS: Results showed that the prefrontal cortex (including Brodmann Area [BA] 10), middle temporal gyrus, and precuneus were activated when performing the PM task compared with baseline. The schizotypal and control groups did not differ in behavioral PM performance. However, participants with schizotypal features showed decreased activations in the inferior and medial frontal lobes (BA 45, and 8). CONCLUSIONS: These results confirmed that the PM network involves prefrontal cortex, including BA 10. The lower activation in prefrontal cortex of individuals with schizotypal features when performing a PM task indicates brain activation abnormality. Notably, this abnormality may occur in the absence of any behavioral manifestation. Our findings support the hypothesis of frontal lobe involvement in PM deficits observed in individuals with schizotypal features.


Assuntos
Mapeamento Encefálico , Lobo Frontal/patologia , Transtornos da Memória/diagnóstico , Transtornos da Memória/patologia , Memória Episódica , Transtorno da Personalidade Esquizotípica/complicações , Adolescente , Feminino , Lobo Frontal/irrigação sanguínea , Humanos , Processamento de Imagem Assistida por Computador , Julgamento , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Estimulação Luminosa , Tempo de Reação , Adulto Jovem
15.
PLoS One ; 8(3): e60191, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23555920

RESUMO

BACKGROUND: Abnormalities in large-scale, structural and functional brain connectivity have been increasingly reported in patients with major depressive disorder (MDD). However, MDD-related alterations in functional interaction between the cerebral hemispheres are still not well understood. Resting state fMRI, which reveals spontaneous neural fluctuations in blood oxygen level dependent signals, provides a means to detect interhemispheric functional coherence. We examined the resting state functional connectivity (RSFC) between the two hemispheres and its relationships with clinical characteristics in MDD patients using a recently proposed measurement named "voxel-mirrored homotopic connectivity (VMHC)". METHODOLOGY/PRINCIPAL FINDINGS: We compared the interhemispheric RSFC, computed using the VMHC approach, of seventeen first-episode drug-naive patients with MDD and seventeen healthy controls. Compared to the controls, MDD patients showed significant VMHC decreases in the medial orbitofrontal gyrus, parahippocampal gyrus, fusiform gyrus, and occipital regions including the middle occipital gyrus and cuneus. In MDD patients, a negative correlation was found between VMHC of the fusiform gyrus and illness duration. Moreover, there were several regions whose VMHC showed significant negative correlations with the severity of cognitive disturbance, including the prefrontal regions, such as middle and inferior frontal gyri, and two regions in the cereballar crus. CONCLUSIONS/SIGNIFICANCE: These findings suggest that the functional coordination between homotopic brain regions is impaired in MDD patients, thereby providing new evidence supporting the interhemispheric connectivity deficits of MDD. The significant correlations between the VMHC and clinical characteristics in MDD patients suggest potential clinical implication of VMHC measures for MDD. Interhemispheric RSFC may serve as a useful screening method for evaluating MDD where neural connectivity is implicated in the pathophysiology.


Assuntos
Cérebro/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Adulto , Estudos de Casos e Controles , Cérebro/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Chin Med J (Engl) ; 124(14): 2136-43, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21933616

RESUMO

BACKGROUND: Functional magnetic resonance is a non-invasive method that can examine brain activity and has been widely used in various fields including jaw movement and pain processing. Temporomandibular disorder (TMD) is one of the most frequent facial pain problems. The objective of this study was to investigate the brain activities using functional magnetic resonance imaging (fMRI) during unilateral maximal voluntary clenching tasks in the TMD synovitis patients with biting pain. METHODS: Fourteen TMD synovitis patients with unilateral biting pain and 14 controls were included in the study. Contralateral biting pain was defined as right molar clenching causing left temporomandibular joint (TMJ) pain. Ipsilateral biting pain was defined as right molar clenching causing right TMJ pain. Symptom Check List-90 (SCL-90) was administered to the patients and controls. Independent sample t-test was used to compare the SCL-90 subscales between the two groups. Unilateral clenching tasks were performed by the patients and controls. Imaging data were analyzed using SPM99. RESULTS: Patients were divided into contralateral TMD biting pain group (n = 8) and ipsilateral TMD biting pain group (n = 6). The SCL-90 subscales were significantly different between the two groups for somatization, depression, anxiety, phobic anxiety, and paranoid ideation. Group analysis of the controls demonstrated brain activations in the inferior frontal gyrus, precentral gyrus, middle frontal gyrus, superior temporal gyrus, and insular. The areas of activation were different between right and left clenching task. In TMJ synovitis patients with contralateral or ipsilateral biting pain, the group analysis showed activations in the inferior frontal gyrus, superior temporal gyrus, medium frontal gyrus, precentral gyrus, and anterior cingulate cortex. CONCLUSIONS: The inferior frontal gyrus and precentral gyrus play essential roles during the unilateral clenching task. Activation of anterior cingulate cortex in the synovitis patients with biting pain was associated with higher levels of psychological distress.


Assuntos
Encéfalo/fisiologia , Dor Facial/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Sinovite/patologia , Articulação Temporomandibular/patologia , Adolescente , Adulto , Encéfalo/metabolismo , Dor Facial/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
J Child Neurol ; 25(7): 849-55, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20595697

RESUMO

The purpose was to examine the brain activation patterns with acupuncture using real acupoint (Liv3) versus sham acupoint in healthy, sedated children using functional magnetic resonance imaging (fMRI). Functional magnetic resonance imaging scans of the brain for 10 healthy, sedated children were taken during stimulation of real acupoint (Liv3 [Taichong]) and a nearby sham acupoint in a randomized order, employing twisting and nontwisting methods using a blocked paradigm using a 2.0-T scanner. The functional data were analyzed by using SPM 99. Various regions of the brain were activated in 2 acupoints. However, the pattern was different for the 2 acupoints. We suggest specific cerebral activation patterns with acupuncture might explain some of its therapeutic effect.


Assuntos
Pontos de Acupuntura , Encéfalo/fisiologia , Terapia por Acupuntura/métodos , Mapeamento Encefálico , Pré-Escolar , Sedação Consciente , Feminino , , Nível de Saúde , Humanos , Imageamento por Ressonância Magnética , Masculino
18.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 44(10): 598-600, 2009 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-20079305

RESUMO

OBJECTIVE: To investigate the types of disc position of the temporomandibular joint (TMJ) and their relationship with age and gender in asymptomatic volunteers by magnetic resonance imaging (MRI). METHODS: A total of 100 asymptomatic volunteers were divided into 5 groups (11-, 21-, 31-, 41-, 51 - 60 years old), 10 male and 10 female were included in each group. A total of 200 TMJs were scanned with Siemens Trio Tim 3.0T MRI system oblique-sagittally at closed- and open-mouth positions. Visual evaluation of MR images were performed on 3 neighbour slices of each TMJ (lateral, central, medial). RESULTS: There was a normal disc-condyle relationship in 59 of the 100 asymptomatic subjects. The normal disc position, anterior disc displacement and insidious anterior disc displacement (IADD) were observed in 140 (70.0%), 14(7.0%) and 46(23.0%)joints respectively, which showed no significant differences among different age groups or between genders (P > 0.05). The maximum mouth opening of the 100 asymptomatic volunteers was (46.3 +/- 5.5) mm, with no significant difference among the various types of disc position (P > 0.05). CONCLUSIONS: Disc displacement does exist in the asymptomatic volunteers, however, its occurrence is not associated with age and gender. IADD is the main type of the disc displacement in asymptomatic volunteers. There is no close relationship between the imaging manifestation of the disc displacement and clinical symptoms.


Assuntos
Transtornos da Articulação Temporomandibular/patologia , Articulação Temporomandibular/anatomia & histologia , Articulação Temporomandibular/patologia , Adolescente , Adulto , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
19.
J Child Neurol ; 23(11): 1267-74, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18984835

RESUMO

We study the effect of acupuncture on brain activation patterns in children with cerebral palsy using functional magnetic resonance imaging (fMRI). fMRI of the whole brain was performed in 11 children with cerebral palsy and 10 healthy children during stimulation of a common acupoint in Traditional Medicine [Liv3 (Taichong)] on the left foot. We use both twisting and nontwisting methods with a blocked paradigm on a 2.0 Tesla MRI scanner. Functional data were analyzed by using Statistical Parametric Mapping software (SPM 99). Both signal increase and decrease in various regions of the brain were found in both groups of children. However, the pattern was different for the 2 groups, especially with decreases in signal regions. We suggest that the observed differences between children with cerebral palsy and healthy children with the stimulation of acupoint Liv3 might be due to blockage of the liver meridian in children with cerebral palsy.


Assuntos
Acupuntura/métodos , Encéfalo/irrigação sanguínea , Paralisia Cerebral/patologia , Paralisia Cerebral/terapia , Imageamento por Ressonância Magnética , Encéfalo/patologia , Encéfalo/fisiopatologia , Mapeamento Encefálico , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Oxigênio/sangue
20.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 42(2): 94-5, 2007 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-17462154

RESUMO

OBJECTIVE: To explore effects of chewing-side preference (CSP) on cerebral cortical response during clenching task with functional magnetic resonance imaging (fMRI). METHODS: Seven patients with left CSP and 7 patients with right CSP were selected to perform the maximum voluntary clenching in intercuspal position, and block designed blood oxygenation level-dependent (BOLD) fMRI scan covering the whole brain was carried out. RESULTS: There was activation in the parahippocampal gyrus in the four patients among seven with left CSP. But there was no activation in the parahippocampal gyrus among the patients with right CSP. CONCLUSIONS: This research shows that the parahippocampal gyrus, which is associated with human memory and study, is activated during clenching task in the patients with left CSP.


Assuntos
Força de Mordida , Lateralidade Funcional/fisiologia , Mastigação/fisiologia , Giro Para-Hipocampal/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , Adulto Jovem
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