The Experts below are selected from a list of 5241 Experts worldwide ranked by ideXlab platform
Takatsune Kumada - One of the best experts on this subject based on the ideXlab platform.
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Visual search and memory search engage extensive overlapping cerebral cortices: an fMRI study.
NeuroImage, 2004Co-Authors: Yuichi Makino, Kazuhiko Yokosawa, Yuji Takeda, Takatsune KumadaAbstract:Previous studies have investigated neural correlates of visual search and memory search independently, but none of those studies examined whether cortical regions involved in these searches are overlapping or segregated by directly comparing the two types of search. In this study, we compared the cortical regions involved in visual search and memory search in the same functional magnetic resonance imaging (fMRI) experiment run on the same subjects, using identical stimuli and time courses of stimulus presentation. The right dorsolateral prefrontal cortex (DLPFC), the left frontal eye field (FEF), the right preCuneus and Cuneus, and the left cerebellum were activated by both visual search and memory search. We suggest that the right DLPFC is associated with the process of monitoring and manipulating multiple elements, while the left FEF is involved in cognitive planning. We also propose that the right preCuneus and Cuneus as well as the left cerebellum are responsible for both spatial and nonspatial shifts of attention, including attentional shifts in long-term memory, although each of these regions has a slightly different role.
Emerson L. Gasparetto - One of the best experts on this subject based on the ideXlab platform.
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Cuneus and fusiform cortices thickness is reduced in trigeminal neuralgia
The journal of headache and pain, 2014Co-Authors: Maud Parise, Tadeu Takao Almodovar Kubo, Thomas M. Doring, Gustavo Tukamoto, Maurice B. Vincent, Emerson L. GasparettoAbstract:Chronic pain disorders are presumed to induce changes in brain grey and white matters. Few studies have focused CNS alterations in trigeminal neuralgia (TN). The aim of this study was to explore changes in white matter microstructure in TN subjects using diffusion tensor images (DTI) with tract-based spatial statistics (TBSS); and cortical thickness changes with surface based morphometry. Twenty-four patients with classical TN (37-67 y-o) and 24 healthy controls, matched for age and sex, were included in the study. Comparing patients with controls, no diffusivity abnormalities of brain white matter were detected. However, a significant reduction in cortical thickness was observed at the left Cuneus and left fusiform cortex in the patients group. The thickness of the fusiform cortex correlated negatively with the carbamazepine dose (p = 0.023). Since the Cuneus and the fusiform gyrus have been related to the multisensory integration area and cognitive processing, as well as the retrieval of shock perception conveyed by Aδ fibers, our results support the role of these areas in TN pathogenesis. Whether such changes occurs as an epiphenomenon secondary to daily stimulation or represent a structural predisposition to TN in the light of peripheral vascular compression is a matter of future studies.
Yuichi Makino - One of the best experts on this subject based on the ideXlab platform.
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Visual search and memory search engage extensive overlapping cerebral cortices: an fMRI study.
NeuroImage, 2004Co-Authors: Yuichi Makino, Kazuhiko Yokosawa, Yuji Takeda, Takatsune KumadaAbstract:Previous studies have investigated neural correlates of visual search and memory search independently, but none of those studies examined whether cortical regions involved in these searches are overlapping or segregated by directly comparing the two types of search. In this study, we compared the cortical regions involved in visual search and memory search in the same functional magnetic resonance imaging (fMRI) experiment run on the same subjects, using identical stimuli and time courses of stimulus presentation. The right dorsolateral prefrontal cortex (DLPFC), the left frontal eye field (FEF), the right preCuneus and Cuneus, and the left cerebellum were activated by both visual search and memory search. We suggest that the right DLPFC is associated with the process of monitoring and manipulating multiple elements, while the left FEF is involved in cognitive planning. We also propose that the right preCuneus and Cuneus as well as the left cerebellum are responsible for both spatial and nonspatial shifts of attention, including attentional shifts in long-term memory, although each of these regions has a slightly different role.
Yi Shao - One of the best experts on this subject based on the ideXlab platform.
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Intrinsic functional connectivity alterations of the primary visual cortex in patients with proliferative diabetic retinopathy: a seed-based resting-state fMRI study
Therapeutic advances in endocrinology and metabolism, 2020Co-Authors: Dong-yi Lan, Nan Jiang, Li-ying Tang, Rong-bin Liang, Yi ShaoAbstract:Purpose In this study, we aimed to investigate the differences in the intrinsic functional connectivity (iFC) of the primary visual cortex (V1), based on resting-state functional magnetic resonance imaging (rs-fMRI), between patients with proliferative diabetic retinopathy (PDR) and healthy controls (HCs). Methods In total, 26 patients (12 males, 14 females) with PDR and 26 HCs (12 males, 14 females), matched for sex, age, and education status, were enrolled in the study. All individuals underwent rs-fMRI scans. We acquired iFC maps and compared the differences between PDR patients and the HCs. Results The PDR group had significantly increased FC between the left V1 and the right middle frontal gyrus (RMFG), and significantly reduced FC between the left V1 and the Cuneus/calcarine/preCuneus. In addition, the PDR patients had significantly increased FC between the right V1 and the right superior frontal gyrus (RSFG), and significantly reduced FC between the right V1 and the Cuneus/calcarine/preCuneus. The individual areas under the curve (AUCs) of FC values for the left V1 were as follows: RMFG (0.871, p
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Altered intrinsic functional connectivity of the primary visual cortex in patients with retinal vein occlusion: a resting-state fMRI study
Quantitative imaging in medicine and surgery, 2020Co-Authors: Qing Yuan, Xu-lin Liao, Wen-qing Shi, Xue-zhi Zhou, Qi Lin, You-lan Min, Nan Jiang, Yi ShaoAbstract:Background To investigate the differences of spontaneous functional connectivity (FC) of the primary visual cortex (V1) between patients with retinal vein occlusion (RVO) and healthy controls (HCs) using resting-state functional magnetic resonance imaging (rs-fMRI) data. Methods Twenty-one patients with RVO in total (11 males, 10 females) and 21 HCs similarly analogue in age and sex background were enrolled and inspected with rs-fMRI. The difference in FC of V1 between two groups were compared using two-sample t-test. We used the receiver operating characteristic (ROC) curve to distinguish average FC values of RVO subjects from HCs. The interrelationships between FC signals of specific cerebrum regions and clinical features in RVOs were assessed with the Pearson's correlation analysis. Results Compared with HCs, FC in left V1 and right middle frontal gyrus increased significantly in RVO group, while FC in left V1 and right Cuneus decreased significantly. Meanwhile, patients with RVO presented increased FC between the right V1 and right middle frontal gyrus, right superior frontal gyrus, but declining FC between right V1 and right Cuneus. The mean FC value between the right Cuneus and the right V1 as well as the left V1 were negative correlated with the foveal thickness of RVO patients. ROC curve analysis of each brain regions showed the accuracy of AUC was excellent. Conclusions RVO involves aberrant FC in V1 in different brain areas including visual-related and cognitive-related region, which might assist to unveil the underlying neural mechanisms of impaired visual function in RVO.
Michael P. Milham - One of the best experts on this subject based on the ideXlab platform.
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Amplitude of low-frequency oscillations in schizophrenia: a resting state fMRI study.
Schizophrenia research, 2009Co-Authors: Matthew J. Hoptman, Xi-nian Zuo, Pamela D. Butler, Daniel C. Javitt, Debra D'angelo, Cristina J. Mauro, Michael P. MilhamAbstract:Recently, a great deal of interest has arisen in resting state fMRI as a measure of tonic brain function in clinical populations. Most studies have focused on the examination of temporal correlation between resting state fMRI low-frequency oscillations (LFOs). Studies on the amplitudes of these low-frequency oscillations are rarely reported. Here, we used amplitude of low-frequency fluctuations (ALFF) and fractional ALFF (fALFF; the relative amplitude that resides in the low frequencies) to examine the amplitude of LFO in schizophrenia. Twenty-six healthy controls and 29 patients with schizophrenia or schizoaffective disorder participated. Our findings show that patients showed reduced low-frequency amplitude in proportion to the total frequency band investigated (i.e., fALFF) in the lingual gyrus, left Cuneus, left insula/superior temporal gyrus, and right caudate and increased fALFF in the medial prefrontal cortex and the right parahippocampal gyrus. ALFF was reduced in patients in the lingual gyrus, Cuneus, and preCuneus and increased in the left parahippocampal gyrus. These results suggest LFO abnormalities in schizophrenia. The implication of these abnormalities for schizophrenic symptomatology is further discussed.
