90 results on '"Shinosaki, K."'
Search Results
2. Wavelet-Crosscorrelation Analysis: Non-Stationary Analysis of Neurophysiological Signals
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Mizuno-Matsumoto, Y., Ukai, S., Ishii, R., Date, S., Kaishima, T., Shinosaki, K., Shimojo, S., Takeda, M., Tamura, S., and Inouye, T.
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- 2005
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3. Right parietal activation during delusional state in episodic interictal psychosis of epilepsy: A report of two cases
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Ishii, R., Canuet, L., Iwase, M., Kurimoto, R., Ikezawa, K., Robinson, S.E., Ukai, S., Shinosaki, K., Hirata, M., Yoshimine, T., and Takeda, M.
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- 2006
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4. Anterior brain activities related to emotional stress.
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Hayashi, T., Mizuno-Matsumoto, Y., Okamoto, E., Ishii, R., Ukai, S., and Shinosaki, K.
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- 2008
5. EEG changes affected by trauma related to earthquakes.
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Okamoto, E., Mizuno-Matsumoto, Y., Hayashi, T., Ishii, R., Ukai, S., and Shinosaki, K.
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- 2008
6. EPA-0443 – Changes of white matter integrity in the corpus callosum by rtms for treatment-resistant depression: a preliminary dti tractography study
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Kita, A., Yamada, S., Ukai, S., Takahashi, S., Tsuji, T., Iwatani, J., Terada, M., and Shinosaki, K.
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- 2014
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7. EPA-0433 – Reduced wm integrity in anterior corpus callosum and its relationship with clinical symptoms in bipolar disorder: a dti tractography study
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Yamada, S., Ukai, S., Takahashi, S., Tsuji, T., Iwatani, J., Tsuda, K., Kita, A., Terada, M., and Shinosaki, K.
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- 2014
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8. Integration of signal processing and medical image for evaluation of brain function on Globus.
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Mizuno-Matsumoto, Y., Date, S., Tabuchi, Y., Tamura, S., Sato, Y., Zorooh, R.A., Shimojo, S., Kadobayashi, Y., Nogawa, T.H., Shinosaki, K., Takeda, M., Osaka, I.T., and Miyahara, H.
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- 1999
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9. P27-10 Relationship between personality stability and brain reaction area under the emotional stimuli
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Mizuno-Matsumoto, Y., Hayashi, T., Okamoto, E., Asakawa, T., Ishii, R., Ukai, S., and Shinosaki, K.
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- 2010
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10. P24-20 Assessment of stress states based on EEG activity using multiple regression analysis
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Hayashi, T., Okamoto, E., Ukai, S., Shinosaki, K., Ishii, R., and Mizuno-Matsumoto, Y.
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- 2010
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11. Inter-Site Eeg Relationships before Widespread Epileptiform Discharges.
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Inouye, T, Iyama, A, Shinosaki, K, Toi, S, and Matsumoto, Y
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- 1995
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12. P03.6 Neuromagnetic oscillatory response during movement observation in Asperger disorder
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Honaga, E., Ukai, S., Ishii, R., Kawaguchi, S., Yamamoto, M., Ogawa, A., Nakahachi, T., Fujita, N., Yoshimine, T., Shinosaki, K., and Takeda, M.
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- 2006
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13. Assessment of psychiatric training program for non-psychiatric residents in a Japanese postgraduate rotation system.
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Takahashi S, Ukai S, Tsuji T, Ueno M, and Shinosaki K
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- 2011
14. An approach to visualization of active position in brain by MEG.
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Takuma, T., Saiwaki, N., Nishida, S., Shinosaki, K., and Takeda, M.
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- 2000
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15. Localization of activated areas and directional EEG patterns during mental arithmetic
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Inouye, T., Shinosaki, K., Iyama, A., and Matsumoto, Y.
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- 1993
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16. Half-field sinusoidally modulated light stimulation at subject's alpha frequency
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Shinosaki, K., Inouye, T., Ukai, S., and Toi, S.
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- 1992
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17. Source localization of spike and wave complexes by use of the spline-Laplacian method
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Hosaka, N., Inouye, T., Shinosaki, K., Toi, S., Matsumoto, Y., and Ishii, R.
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- 1996
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18. Real-world outcome of rTMS treatment for depression within the Japanese public health insurance system: Registry data from Kansai TMS network.
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Imazu S, Ikeda S, Toi Y, Sano S, Kanazawa T, Shinosaki K, Tsukuda B, Kita A, Kuroda K, and Takahashi S
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- Humans, Male, Female, Middle Aged, Japan, Adult, Aged, Treatment Outcome, Dorsolateral Prefrontal Cortex, Depressive Disorder, Major therapy, Insurance, Health statistics & numerical data, East Asian People, Transcranial Magnetic Stimulation methods, Registries
- Abstract
This study registered consecutive cases to elucidate the efficacy of rTMS treatment for depression within the Japanese public health insurance system. Of the 102 patients with depression who received rTMS over the left dorsolateral prefrontal cortex, 44 (43.1 %) patients reached remission and 14 (13.7 %) patients did not reach remission but responded to treatment. No serious adverse events occurred. Low baseline HAMD-17 score was associated with remission after rTMS treatment. Favorable outcomes of rTMS treatment were shown in this cohort within the Japanese public insurance system. Our results provide insights into rTMS treatment for depression in real-world clinical setting., Competing Interests: Declaration of Competing Interest Authors Imazu, Ikeda, Shinosaki, and Takahashi have received speaker honoraria from Teijin Pharma Limited. Author Kanazawa has received materials supervision fee from Teijin Pharma Limited., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)
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- 2024
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19. A prospective multicenter validation study of a machine learning algorithm classifier on quantitative electroencephalogram for differentiating between dementia with Lewy bodies and Alzheimer's dementia.
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Suzuki Y, Suzuki M, Shigenobu K, Shinosaki K, Aoki Y, Kikuchi H, Baba T, Hashimoto M, Araki T, Johnsen K, Ikeda M, and Mori E
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- Algorithms, Diagnosis, Differential, Electroencephalography, Humans, Machine Learning, Prospective Studies, Alzheimer Disease diagnosis, Lewy Body Disease diagnosis
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Background and Purpose: An early and accurate diagnosis of Dementia with Lewy bodies (DLB) is critical because treatments and prognosis of DLB are different from Alzheimer's disease (AD). This study was carried out in Japan to validate an Electroencephalography (EEG)-derived machine learning algorithm for discriminating DLB from AD which developed based on a database of EEG records from two different European countries., Methods: In a prospective multicenter study, patients with probable DLB or with probable AD were enrolled in a 1:1 ratio. A continuous EEG segment of 150 seconds was recorded, and the EEG data was processed using MC-004, the EEG-based machine learning algorithm, with all clinical information blinded except for age and gender., Results: Eighteen patients with probable DLB and 21 patients with probable AD were the included for the analysis. The performance of MC-004 differentiating probable DLB from probable AD was 72.2% (95% CI 46.5-90.3%) for sensitivity, 85.7% (63.7-97.0%) for specificity, and 79.5% (63.5-90.7%) for accuracy. When limiting to subjects taking ≤5 mg donepezil, the sensitivity was 83.3% (95% CI 51.6-97.9), the specificity 89.5% (66.9-98.7), and the accuracy 87.1% (70.2-96.4)., Conclusions: MC-004, the EEG-based machine learning algorithm, was able to discriminate between DLB and AD with fairly high accuracy. MC-004 is a promising biomarker for DLB, and has the potential to improve the detection of DLB in a diagnostic process., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: YS, MS,TA and EM report grants and personal fees from Mentis Cura (https://www.mentiscura.com) during the conduct of the study. KShig, KShin, YA, HK, TB and MH report grants from Mentis Cura, during the conduct of the study. KJ is an employee of Mentis Cura. All the authors have sufficiently participated in the work and take responsibility for the content and agree to transfer copyright to PLOS. We disclose potential conflicts of interest and describe their financial support. This does not alter our adherence to PLOS ONE policies on sharing data and materials. Our manuscript contains no extractions from other copyrighted works. We confirm that this manuscript has not been accepted for publication elsewhere, is not being considered for publication elsewhere, and does not duplicate previously published material. I confirm that all the authors consent to publication of this manuscript.
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- 2022
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20. Widespread white matter microstructural abnormalities and cognitive impairment in schizophrenia, bipolar disorder, and major depressive disorder: Tract-based spatial statistics study.
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Yamada S, Takahashi S, Ohoshi Y, Ishida T, Tsuji T, Shinosaki K, Terada M, and Ukai S
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Competing Interests: Declaration of Competing Interest Shinichi Yamada, Shun Takahashi, Yuji Ohoshi, Takuya Ishida, Tomikimi Tsuji, Kazuhiro Shinosaki, Masaki Terada, Satoshi Ukai declare that there are no conflicts of interest related to the study.
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- 2020
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21. Microstructural abnormalities in callosal fibers and their relationship with cognitive function in schizophrenia: A tract-specific analysis study.
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Ohoshi Y, Takahashi S, Yamada S, Ishida T, Tsuda K, Tsuji T, Terada M, Shinosaki K, and Ukai S
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- Adult, Anisotropy, Executive Function physiology, Female, Humans, Male, Middle Aged, Neuropsychological Tests, Cognition physiology, Corpus Callosum diagnostic imaging, Diffusion Tensor Imaging methods, Schizophrenia diagnostic imaging, Schizophrenic Psychology, White Matter diagnostic imaging
- Abstract
Introduction: The corpus callosum serves the essential role of relaying cognitive information between the homologous regions in the left and the right hemispheres of the brain. Cognitive impairment is a core dysfunction of schizophrenia, but much of its pathophysiology is unknown. The aim of this study was to elucidate the association between microstructural abnormalities of the corpus callosum and cognitive dysfunction in schizophrenia., Methods: We examined stepwise multiple regression analysis to investigate the relationship of the fractional anisotropy (FA) of callosal fibers in each segment with z-scores of each brief assessment of cognition in schizophrenia subtest and cognitive composite score in all subjects (19 patients with schizophrenia [SZ group] and 19 healthy controls [HC group]). Callosal fibers were separated into seven segments based on their cortical projection using tract-specific analysis of diffusion tensor imaging., Results: The FA of callosal fibers in the temporal segment was significantly associated with z-scores of token motor test, Tower of London test, and the composite score. In the SZ group, the FA of callosal fibers in the temporal segment was significantly associated with the z-score of the Tower of London test. In addition, the FA of callosal fibers in temporal segment showed significant negative association with the positive and negative syndrome scale negative score in the SZ group. Compared to the HC group, the FA in temporal segment was significantly decreased in the SZ group., Conclusion: Our results suggest that microstructural abnormalities in the callosal white matter fibers connecting bilateral temporal lobe cortices contribute to poor executive function and severe negative symptom in patients with schizophrenia., (© 2019 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.)
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- 2019
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22. Widespread abnormalities in white matter integrity and their relationship with duration of illness in temporal lobe epilepsy.
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Tsuda K, Tsuji T, Ishida T, Takahashi S, Yamada S, Ohoshi Y, Terada M, Shinosaki K, and Ukai S
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Objective: Elucidation of abnormal connections throughout the whole brain is necessary to understand temporal lobe epilepsy (TLE). We examined abnormalities in whole-brain white matter integrity and their relationship with duration of illness in patients with TLE., Methods: The subjects were 15 patients with TLE and 17 healthy controls. Mean duration of illness in the TLE group was 21.6 years. Tract-based spatial statistics (TBSS) were used for diffusion tensor imaging (DTI) analysis. Four diffusion tensor metrics, that is, fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were calculated and then examined for differences between the TLE and healthy control groups. We also examined for correlations between DTI parameters and duration of illness in the TLE group., Results: In the TLE group, compared with the healthy control group, FA was reduced, and MD and RD were increased, not only in the limbic and temporal lobe regions and their directly connecting regions in both hemispheres, but also in remote white matter regions. Duration of illness showed a significant negative correlation with mean whole-brain FA and a significant positive correlation with both mean whole-brain MD and RD. Brain regions showing correlation between disease duration and DTI metrics also extended to the limbic area and its connecting regions, and to remote white matter regions., Significance: The results of this study suggest that widespread abnormalities in white matter integrity in patients with TLE are associated with long-term disease.
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- 2018
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23. Interhemispheric disconnectivity in the sensorimotor network in bipolar disorder revealed by functional connectivity and diffusion tensor imaging analysis.
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Ishida T, Donishi T, Iwatani J, Yamada S, Takahashi S, Ukai S, Shinosaki K, Terada M, and Kaneoke Y
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Background: Little is known regarding interhemispheric functional connectivity (FC) abnormalities via the corpus callosum in subjects with bipolar disorder (BD), which might be a key pathophysiological basis of emotional processing alterations in BD., Methods: We performed tract-based spatial statistics (TBSS) using diffusion tensor imaging (DTI) in 24 healthy control (HC) and 22 BD subjects. Next, we analyzed the neural networks with independent component analysis (ICA) in 32HC and 25 BD subjects using resting-state functional magnetic resonance imaging., Results: In TBSS analysis, we found reduced fractional anisotropy (FA) in the corpus callosum of BD subjects. In ICA, functional within-connectivity was reduced in two clusters in the sensorimotor network (SMN) (right and left primary somatosensory areas) of BD subjects compared with HCs. FC between the two clusters and FA values in the corpus callosum of BD subjects was significantly correlated. Further, the functional within-connectivity was related to Young Mania Rating Scale (YMRS) total scores in the right premotor area in the SMN of BD subjects., Limitations: Almost all of our BD subjects were taking several medications which could be a confounding factor., Conclusions: Our findings suggest that interhemispheric FC dysfunction in the SMN is associated with the impaired nerve fibers in the corpus callosum, which could be one of pathophysiological bases of emotion processing dysregulation in BD patients.
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- 2017
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24. Elucidating the aberrant brain regions in bipolar disorder using T1-weighted/T2-weighted magnetic resonance ratio images.
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Ishida T, Donishi T, Iwatani J, Yamada S, Takahashi S, Ukai S, Shinosaki K, Terada M, and Kaneoke Y
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- Adult, Bipolar Disorder physiopathology, Brain physiopathology, Case-Control Studies, Cerebellum diagnostic imaging, Cerebellum physiopathology, Corpus Callosum diagnostic imaging, Corpus Callosum physiopathology, Female, Gray Matter diagnostic imaging, Gray Matter physiopathology, Humans, Internal Capsule diagnostic imaging, Internal Capsule physiopathology, Male, Middle Aged, White Matter diagnostic imaging, White Matter physiopathology, Bipolar Disorder diagnostic imaging, Brain diagnostic imaging, Diffusion Tensor Imaging methods
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Although diffusion tensor imaging (DTI) have revealed brain abnormalities in bipolar disorder (BD) subjects, DTI methods might not detect disease-related abnormalities in the white matter (WM) where nerve fibers are crossing. We investigated BD myelin-related abnormal brain regions in both gray matter and WM for 29 BD and 33 healthy control (HC) participants using T1-weighted (T1w)/T2-weighted (T2w) ratio images that increase myelin-related contrast irrespective of nerve fiber orientation. To check effect of the brain volume, the results were compared with those of voxel-based morphometry (VBM). We found significantly lower T1w/T2w signal intensity in broad WM regions in BD subjects, including the corpus callosum, corona radiata, internal capsule, middle cerebellar peduncle and cerebellum. Regional volume reduction was found in the WM bilateral posterior thalami and retrolenticular part of the internal capsules of BD subjects. We also performed tract-based spatial statistics (TBSS) in 25 BD and 24 HC participants and compared those for the T1w/T2w ratio images. Both methods detected the BD corpus callosum abnormality. Further, the ratio images detected the corona radiata and the cerebellar abnormality in BD. These results suggest that T1w/T2w ratio image analysis could take a complementary role with the DTI method in elucidating myelin-related abnormalities in BD., (Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.)
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- 2017
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25. Omega-3 fatty acids related to cognitive impairment in patients with schizophrenia.
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Satogami K, Takahashi S, Yamada S, Ukai S, and Shinosaki K
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Cognitive impairment is strongly associated with functional outcome in patients with schizophrenia but its pathophysiology remains largely unclear. Involvement of omega-3 fatty acids in the cognitive function of healthy individuals and patients with neuropsychiatric disease has received increasing attention. The aim of this study was to examine the relationship between omega-3 fatty acids with cognitive function, social function, and psychiatric symptoms in patients with schizophrenia. The subjects included 30 patients with schizophrenia or schizoaffective disorder. Psychiatric symptoms, cognitive function, and social function were assessed using the Positive and Negative Syndrome Scale, the Brief Assessment of Cognition in Schizophrenia (BACS), and the Social Functioning Scale (SFS), respectively. Blood serum omega-3 fatty acids were assessed using gas chromatography. The BACS composite score was significantly correlated with blood eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels. In addition, a daily dose of antipsychotic medication was negatively and significantly correlated with the blood DHA level and with the BACS composite score. Step-wise multiple regression analyses demonstrated that the SFS score was significantly associated with the BACS composite score. Our results indicate that reduced blood omega-3 fatty acids are associated with cognitive impairment, which then impacts social functioning outcomes in schizophrenia.
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- 2017
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26. Schizophrenia-like symptoms in a patient with Leigh syndrome.
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Satogami K, Takahashi S, Kose A, and Shinosaki K
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- Adolescent, Humans, Male, Schizophrenia etiology, Leigh Disease complications, Psychotic Disorders etiology
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Leigh syndrome is a mitochondrial disease characterized by subacute necrotizing encephalomyelopathy. Almost all cases of Leigh syndrome develop at infancy or early childhood and die within several years due to rapidly progressive muscle weakness and respiratory failure. Here, we present a rare case of a patient who developed Leigh syndrome associated with thiamine-responsive pyruvate dehydrogenase-complex deficiency at 2 years of age and has survived to adolescence through effective high dose thiamin therapy. At 15 years of age, the patient presented persecutory delusions and auditory hallucinations, suggesting an association between mitochondrial dysfunction and schizophrenia-like psychotic symptoms., (Copyright © 2016 Elsevier B.V. All rights reserved.)
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- 2017
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27. Evaluation of regional cerebral blood flow in patient with atypical senile dementia with asymmetrical calcification.
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Shoyama M, Ukai S, and Shinosaki K
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- Aged, 80 and over, Alzheimer Disease complications, Brain diagnostic imaging, Calcinosis complications, Female, Humans, Neurofibrillary Tangles diagnostic imaging, Tomography Scanners, X-Ray Computed, Tomography, Emission-Computed, Single-Photon, Alzheimer Disease diagnosis, Brain blood supply, Brain pathology, Calcinosis diagnosis, Cerebrovascular Circulation, Neurofibrillary Tangles pathology
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We report an 83-year-old woman with atypical senile dementia with Fahr-type calcification. Brain computed tomography demonstrated asymmetrical calcification predominant in the basal ganglia on the right side and pronounced diffuse cortical atrophy in the frontotemporal areas. The patient was clinically diagnosed with diffuse neurofibrillary tangles with calcification. Brain single photon emission computed tomography findings revealed that cerebral blood flow was reduced on the right side, as compared with the left side, in widespread areas. Hemispheric asymmetry in both calcification and cerebral blood flow suggests a relationship between calcification and vascular changes., (© 2015 The Authors. Psychogeriatrics © 2015 Japanese Psychogeriatric Society.)
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- 2015
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28. Use of T1-weighted/T2-weighted magnetic resonance ratio images to elucidate changes in the schizophrenic brain.
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Iwatani J, Ishida T, Donishi T, Ukai S, Shinosaki K, Terada M, and Kaneoke Y
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- Adult, Case-Control Studies, Cerebral Cortex pathology, Female, Gray Matter pathology, Humans, Male, Middle Aged, Myelin Sheath pathology, Schizophrenia diagnosis, White Matter pathology, Magnetic Resonance Imaging methods, Schizophrenia pathology
- Abstract
Introduction: One leading hypothesis suggests that schizophrenia (SZ) is a neurodevelopmental disorder caused by genetic defects in association with environmental risk factors that affect synapse and myelin formation. Recent magnetic resonance imaging (MRI) studies of SZ brain showed both gray matter (GM) reduction and white matter (WM) fractional anisotropy reduction. In this study, we used T1-weighted (T1w)/T2-weighted (T2w) MRI ratio images, which increase myelin-related signal contrast and reduce receiver-coil bias., Methods: We measured T1w/T2w ratio image signal intensity in 29 patients with SZ and 33 healthy controls (HCs), and then compared them against bias-corrected T1w images., Results: Mean T1w/T2w ratio signal intensity values across all SZ GM and WM voxels were significantly lower than those for the HC values (analysis of covariance with age, gender, handedness, and premorbid intelligence quotient as nuisance covariates). SZ mean WM T1w/T2w ratio values were related to Global Assessment of Functioning (GAF) scores and were inversely related to the positive psychotic symptoms of the Positive and Negative Syndrome Scale. Voxel-based analysis revealed significantly lower T1w/T2w ratio image signal intensity values in the right ventral putamen in SZ GM. T1w image intensities did not differ between the SZ and HC groups., Conclusions: T1-weighted/T2-weighted ratio imaging increased the detectability of SZ pathological changes. Reduced SZ brain signal intensity is likely due to diminished myelin content; therefore, mapping myelin-related SZ brain changes using T1w/T2w ratio images may be useful for studies of SZ brain abnormalities.
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- 2015
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29. Alterations of Regional Cerebral Blood Flow in Tinnitus Patients as Assessed Using Single-Photon Emission Computed Tomography.
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Ueyama T, Donishi T, Ukai S, Yamamoto Y, Ishida T, Tamagawa S, Hotomi M, Shinosaki K, Yamanaka N, and Kaneoke Y
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- Adult, Female, Humans, Male, Middle Aged, Tinnitus diagnostic imaging, Tomography, Emission-Computed, Single-Photon, Cerebrovascular Circulation, Tinnitus physiopathology
- Abstract
Tinnitus is the perception of phantom sound without an external auditory stimulus. Using neuroimaging techniques, such as positron emission tomography, electroencephalography, magnetoencephalography, and functional magnetic resonance imaging (fMRI), many studies have demonstrated that abnormal functions of the central nervous system are closely associated with tinnitus. In our previous research, we reported using resting-state fMRI that several brain regions, including the rectus gyrus, cingulate gyrus, thalamus, hippocampus, caudate, inferior temporal gyrus, cerebellar hemisphere, and medial superior frontal gyrus, were associated with tinnitus distress and loudness. To reconfirm these results and probe target regions for repetitive transcranial magnetic stimulation (rTMS), we investigated the regional cerebral blood flow (rCBF) between younger tinnitus patients (<60 years old) and the age-matched controls using single-photon emission computed tomography and easy Z-score imaging system. Compared with that of controls, the rCBF of tinnitus patients was significantly lower in the bilateral medial superior frontal gyri, left middle occipital gyrus and significantly higher in the bilateral cerebellar hemispheres and vermis, bilateral middle temporal gyri, right fusiform gyrus. No clear differences were observed between tinnitus patients with normal and impaired hearing. Regardless of the assessment modality, similar brain regions were identified as characteristic in tinnitus patients. These regions are potentially involved in the pathophysiology of chronic subjective tinnitus.
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- 2015
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30. Microstructural abnormalities in anterior callosal fibers and their relationship with cognitive function in major depressive disorder and bipolar disorder: a tract-specific analysis study.
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Yamada S, Takahashi S, Ukai S, Tsuji T, Iwatani J, Tsuda K, Kita A, Sakamoto Y, Yamamoto M, Terada M, and Shinosaki K
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- Adult, Anisotropy, Bipolar Disorder complications, Case-Control Studies, Cognition Disorders complications, Depressive Disorder, Major complications, Diffusion Tensor Imaging, Female, Humans, Male, Middle Aged, Neuroimaging, Neuropsychological Tests, Young Adult, Bipolar Disorder pathology, Cognition Disorders pathology, Corpus Callosum pathology, Depressive Disorder, Major pathology, White Matter pathology
- Abstract
Background: The corpus callosum modulates interhemispheric communication and cognitive processes. It has been suggested that white matter abnormalities in the corpus callosum are related to the pathophysiology of major depressive disorder (MDD) and bipolar disorder (BD). The aim of this study was to examine microstructural abnormalities in callosal fibers separated by their connection to functional brain regions and determine the relationship of these abnormalities with cognitive function in MDD and BD., Methods: The subjects were 18 patients with MDD, 20 patients with BD, and 21 healthy controls. The callosal fibers were divided into 6 segments based on their cortical projection using tract-specific analysis of diffusion tensor imaging. We examined differences in the fractional anisotropy (FA) of callosal fibers in six segments among the three subject groups and examined the correlation between the FA in each segment and cognitive performance in the 3 groups., Results: The FA of anterior callosal fibers were reduced significantly in the MDD and BD groups compared to those in the HC group, and the FA of anterior callosal fibers correlated significantly with the raw scores of the digit sequencing task and symbol coding in the MDD group., Limitations: The patients were medicated at the time of scanning, and the MDD and BD groups were not matched for symptom severity., Conclusions: Our results suggest that MDD and BD have similar microstructural abnormalities in anterior callosal fibers connecting bilateral frontal cortices, and these abnormalities may be related to impairment of working memory and attention in MDD., (Copyright © 2014 Elsevier B.V. All rights reserved.)
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- 2015
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31. Reduction of cortical excitability and increase of thalamic activity in a low-frequency rTMS treatment for chronic tinnitus.
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Takahashi S, Ukai S, Tsuji T, Ueyama T, Kono M, Yamanaka N, and Shinosaki K
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- Cerebrovascular Circulation physiology, Chronic Disease, Female, Humans, Middle Aged, Positron-Emission Tomography, Tomography, Emission-Computed, Single-Photon, Cerebral Cortex physiopathology, Thalamus physiopathology, Tinnitus therapy, Transcranial Magnetic Stimulation methods
- Abstract
Low-frequency repetitive transcranial magnetic stimulation (rTMS) has received increasing attention for the treatment of tinnitus, but its therapeutic mechanisms are unclear. We performed low-frequency rTMS treatment for a patient with chronic tinnitus and examined changes of cortical excitability and cerebral blood flow using paired-pulse TMS and single-photon emission computed tomography. After the rTMS treatment, tinnitus loudness was decreased, cortical excitability was reduced, and blood flow in the thalamus was increased. Our results suggest that low-frequency rTMS treatment reduces tinnitus loudness by an inhibitory effect on the cortical excitability and a remote activation effect on the thalamus through the corticothalamic networks.
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- 2015
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32. Brain regions responsible for tinnitus distress and loudness: a resting-state FMRI study.
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Ueyama T, Donishi T, Ukai S, Ikeda Y, Hotomi M, Yamanaka N, Shinosaki K, Terada M, and Kaneoke Y
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- Adult, Aged, Female, Humans, Male, Middle Aged, Nerve Net physiopathology, Young Adult, Brain physiopathology, Depression complications, Loudness Perception, Magnetic Resonance Imaging, Rest, Tinnitus complications, Tinnitus physiopathology
- Abstract
Subjective tinnitus is characterized by the perception of phantom sound without an external auditory stimulus. We hypothesized that abnormal functionally connected regions in the central nervous system might underlie the pathophysiology of chronic subjective tinnitus. Statistical significance of functional connectivity (FC) strength is affected by the regional autocorrelation coefficient (AC). In this study, we used resting-state functional MRI (fMRI) and measured regional mean FC strength (mean cross-correlation coefficient between a region and all other regions without taking into account the effect of AC (rGC) and with taking into account the effect of AC (rGCa) to elucidate brain regions related to tinnitus symptoms such as distress, depression and loudness. Consistent with previous studies, tinnitus loudness was not related to tinnitus-related distress and depressive state. Although both rGC and rGCa revealed similar brain regions where the values showed a statistically significant relationship with tinnitus-related symptoms, the regions for rGCa were more localized and more clearly delineated the regions related specifically to each symptom. The rGCa values in the bilateral rectus gyri were positively correlated and those in the bilateral anterior and middle cingulate gyri were negatively correlated with distress and depressive state. The rGCa values in the bilateral thalamus, the bilateral hippocampus, and the left caudate were positively correlated and those in the left medial superior frontal gyrus and the left posterior cingulate gyrus were negatively correlated with tinnitus loudness. These results suggest that distinct brain regions are responsible for tinnitus symptoms. The regions for distress and depressive state are known to be related to depression, while the regions for tinnitus loudness are known to be related to the default mode network and integration of multi-sensory information.
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- 2013
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33. Reduction of cortical GABAergic inhibition correlates with working memory impairment in recent onset schizophrenia.
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Takahashi S, Ukai S, Kose A, Hashimoto T, Iwatani J, Okumura M, Tsuji T, and Shinosaki K
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- Adult, Analysis of Variance, Antipsychotic Agents pharmacology, Antipsychotic Agents therapeutic use, Benzodiazepines pharmacology, Benzodiazepines therapeutic use, Electromyography, Evoked Potentials, Motor drug effects, Female, Humans, Male, Motor Cortex drug effects, Neural Inhibition drug effects, Neural Inhibition physiology, Neuropsychological Tests, Psychiatric Status Rating Scales, Schizophrenia drug therapy, Transcranial Magnetic Stimulation, Verbal Learning drug effects, Verbal Learning physiology, Young Adult, Cerebral Cortex physiopathology, Memory Disorders etiology, Memory, Short-Term physiology, Schizophrenia complications, Schizophrenia pathology, Schizophrenic Psychology
- Abstract
Background: Cognitive impairments are present during the early course of schizophrenia, and the contribution of GABAergic dysfunction to these cognitive impairments has received increasing attention. Cortical GABAergic inhibition can be assessed using short-interval intracortical inhibition (SICI) in a paired-pulse transcranial magnetic stimulation (ppTMS). The aim of this study was to examine the relationship between cortical GABAergic inhibition and cognitive function in recent onset schizophrenia patients using ppTMS and a neuropsychological battery., Methods: The subjects were 20 healthy controls (HC group) and 20 patients with schizophrenia whose duration of illness was less than three years (SZ group). All subjects underwent ppTMS measurements of SICI and intracortical facilitation (ICF), and cognitive performance of the SZ group was assessed using the Brief Assessment of Cognition in Schizophrenia Japanese-language version. We examined group differences in ppTMS measurements (resting motor threshold, SICI, and ICF). In the SZ group, we assessed the relationship between SICI and cognitive performance, and the relationships between SICI and age, duration of illness, medications, and psychopathology., Results: The SZ group showed a significant reduction of SICI compared to the HC group, and demonstrated a significant correlation between the reduction of SICI and impaired performance of a working memory task. The HC and the SZ groups did not differ significantly in resting motor threshold and ICF. The SZ group did not show any significant correlations between SICI and age, duration of illness, medications, or psychopathology., Conclusions: Our results suggest that the reduction of cortical GABAergic inhibition is related to impairment of working memory in patients with recent onset schizophrenia., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
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34. Cerebral blood flow in the subgenual anterior cingulate cortex and modulation of the mood-regulatory networks in a successful rTMS treatment for major depressive disorder.
- Author
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Takahashi S, Ukai S, Tsuji T, Kose A, Shoyama M, Yamamoto M, Okumura M, and Shinosaki K
- Subjects
- Depressive Disorder, Major diagnostic imaging, Female, Functional Laterality, Gyrus Cinguli diagnostic imaging, Humans, Imaging, Three-Dimensional, Middle Aged, Psychiatric Status Rating Scales, Time Factors, Tomography, Emission-Computed, Single-Photon, Transcranial Magnetic Stimulation methods, Treatment Outcome, Cerebrovascular Circulation physiology, Depressive Disorder, Major pathology, Depressive Disorder, Major therapy, Gyrus Cinguli blood supply
- Abstract
The subgenual anterior cingulate cortex (Cg25) has been reported to be a node of mood-regulatory networks. Using a responder and a non-responder of repetitive transcranial magnetic stimulation (rTMS) for depression, we examined pre/post-treatment cerebral blood flow (CBF) in the Cg25 and treatment-related CBF changes in cortical/subcortical regions. In the responder, pre-treatment Cg25 perfusion was higher and was decreased after treatment, in addition, CBF was increased in the frontal and parietal regions and decreased in the hippocampus and basal ganglia. Our results suggest that rTMS treatment response may be related to pre-treatment Cg25 activity and modulation of the Cg25 and mood-regulatory networks.
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- 2013
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35. Variance and autocorrelation of the spontaneous slow brain activity.
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Kaneoke Y, Donishi T, Iwatani J, Ukai S, Shinosaki K, and Terada M
- Subjects
- Adult, Brain cytology, Brain metabolism, Female, Humans, Kinetics, Magnetic Resonance Imaging, Male, Neurons cytology, Oxygen blood, Periodicity, Brain physiology, Functional Neuroimaging, Pattern Recognition, Automated
- Abstract
Slow (<0.1 Hz) oscillatory activity in the human brain, as measured by functional magnetic imaging, has been used to identify neural networks and their dysfunction in specific brain diseases. Its intrinsic properties may also be useful to investigate brain functions. We investigated the two functional maps: variance and first order autocorrelation coefficient (r(1)). These two maps had distinct spatial distributions and the values were significantly different among the subdivisions of the precuneus and posterior cingulate cortex that were identified in functional connectivity (FC) studies. The results reinforce the functional segregation of these subdivisions and indicate that the intrinsic properties of the slow brain activity have physiological relevance. Further, we propose a sample size (degree of freedom) correction when assessing the statistical significance of FC strength with r(1) values, which enables a better understanding of the network changes related to various brain diseases.
- Published
- 2012
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36. Brain activity during the Clock-Drawing Test: multichannel near-infrared spectroscopy study.
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Shoyama M, Nishioka T, Okumura M, Kose A, Tsuji T, Ukai S, and Shinosaki K
- Subjects
- Adult, Dominance, Cerebral physiology, Female, Humans, Male, Neuroimaging methods, Neuroimaging statistics & numerical data, Oxyhemoglobins metabolism, Prefrontal Cortex metabolism, Spectroscopy, Near-Infrared methods, Temporal Lobe metabolism, Neuroimaging psychology, Psychological Tests statistics & numerical data, Psychomotor Performance physiology, Spectroscopy, Near-Infrared statistics & numerical data
- Abstract
The Clock-Drawing Test (CDT) is widely used in clinical practice for the screening of dementia. However, neural activity during real clock drawing has not been investigated due to motion artifacts. In the present study, we examined brain activity during real clock drawing using multichannel near-infrared spectroscopy (NIRS). We measured hemoglobin concentration changes in the prefrontal and temporal surface areas during clock drawing using 52-channel NIRS. Data obtained from 37 right-handed healthy volunteers were analyzed. We found significant increases in oxy-Hb in more than 96.2% of the channels (false-discovery rate corrected, p < .025). The time required for CDT performance showed a negative correlation with changes in oxy-Hb in the prefrontal region (r = -.529, p = .002). The mean value for oxy-Hb changes was higher in the left hemisphere in 20 subjects (54%) and in the right hemisphere in 17 subjects (46%). The NIRS/CDT combination is acceptable as a clinical tool, as the method has the advantages of direct measurement of cortical activation with high temporal resolution. Our results confirm the aspects of the CDT involving the frontal-lobe battery.
- Published
- 2011
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37. Chronic repetitive transcranial magnetic stimulation increases hippocampal neurogenesis in rats.
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Ueyama E, Ukai S, Ogawa A, Yamamoto M, Kawaguchi S, Ishii R, and Shinosaki K
- Subjects
- Animals, Dentate Gyrus anatomy & histology, Dentate Gyrus growth & development, Hippocampus anatomy & histology, Male, Rats, Rats, Sprague-Dawley, Hippocampus growth & development, Neurogenesis, Transcranial Magnetic Stimulation
- Abstract
Aim: While the underlying therapeutic mechanisms of repetitive transcranial magnetic stimulation (rTMS) treatment for depression remain unclear, recent animal studies have suggested that hippocampal neurogenesis might be required for the effects of antidepressant treatments including antidepressant drugs and electroconvulsive therapy. The aim of this study was to examine chronic rTMS effects on hippocampal neurogenesis in rats., Methods: Using a 70-mm figure-of-eight coil, the stimulating parameters were set to 25 Hz and 70% of the rTMS device's maximum power. For 14 consecutive days, bromodeoxyuridine (BrdU) and 1000 pulses of rTMS were administered daily. Cell proliferation in the dentate gyrus was examined with immunohistochemistry., Results: In the rTMS-treated group, BrdU-positive cells were significantly increased in the dentate gyrus., Conclusion: Our results suggest that hippocampal neurogenesis might be involved in the antidepressant effects of chronic rTMS., (© 2011 The Authors. Psychiatry and Clinical Neurosciences © 2011 Japanese Society of Psychiatry and Neurology.)
- Published
- 2011
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38. Evaluation of regional cerebral blood flow in a patient with musical hallucinations.
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Shoyama M, Ukai S, Kitabata Y, Yamamoto M, Okumura M, Kose A, Tsuji T, and Shinosaki K
- Subjects
- Audiometry methods, Cerebral Cortex diagnostic imaging, Female, Hallucinations diagnostic imaging, Hallucinations pathology, Humans, Middle Aged, Regional Blood Flow physiology, Tomography, Emission-Computed, Single-Photon methods, Brain Mapping, Cerebral Cortex blood supply, Hallucinations physiopathology, Music
- Abstract
A 52-year-old woman with musical hallucinations was examined using brain single photon emission computed tomography (SPECT) with 99mTc-ECD. Changes in regional cerebral blood flow (rCBF) after carbamazepine treatment were assessed using a three-dimensional stereotaxic ROI template. Following treatment, rCBF was decreased in the subcortical structures and increased in the global cortical regions. From our findings, we propose that rCBF values in subcortical structures represent abnormalities similar to those reported in previous reports or other psychiatric disorders, while those in cortical regions suggest background brain dysfunctions that result in generation of musical hallucinations.
- Published
- 2010
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39. Maternal smoking during pregnancy and offspring attention-deficit/hyperactivity disorder: a case-control study in Japan.
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Yoshimasu K, Kiyohara C, Minami T, Yoshikawa N, Kihira S, Toyonaga K, Yamamoto A, Shinosaki K, Yamashita H, and Miyashita K
- Subjects
- Adolescent, Adult, Case-Control Studies, Child, Female, Humans, Japan epidemiology, Male, Models, Statistical, Odds Ratio, Pregnancy, Reproducibility of Results, Tobacco Smoke Pollution adverse effects, Asian People statistics & numerical data, Attention Deficit Disorder with Hyperactivity epidemiology, Maternal Behavior psychology, Prenatal Exposure Delayed Effects psychology, Smoking adverse effects
- Abstract
Although maternal smoking during pregnancy has been shown to be associated with an increased risk of offspring attention-deficit/hyperactivity disorder (ADHD) in Western countries, there is no empirical evidence in non-Caucasian. Purpose of the present study is to examine the relationship between maternal smoking during pregnancy and offspring ADHD in Japanese population. A case-control study design was adopted. A total of 90 pairs of children with ADHD and mothers as well as 270 corresponding control pairs were recruited throughout the study period. A psychiatrist interviewed all the mothers of children with ADHD and control children and elicited information regarding their lifestyles during pregnancy, including active and passive smoking or drinking habits, as well as psychosocial and perinatal factors. Diagnosis of ADHD was made by each physician in charge according to DSM-IV diagnostic criteria. Logistic regression analysis was used to calculate odds ratios (OR) and 95% confidence intervals (CI) with adjustments for other possible confounding factors. Maternal active smoking during pregnancy was associated with an approximately twofold increased risk of offspring ADHD, even after adjusting for socioeconomic and perinatal confounding factors (OR 1.8 95% CI 0.9-3.6). However, the association was obviously attenuated when factors regarding parental psychopathological vulnerability were controlled (OR 1.3 95% CI 0.6-2.9). On the other hand, maternal passive smoking during pregnancy failed to show any material association with ADHD. These results suggested that a significant part of the association between maternal smoking during pregnancy, and ADHD might be explained by genetic factors including parental psychopathological vulnerability., (© Springer-Verlag 2009)
- Published
- 2009
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40. Genetic polymorphisms in dopamine- and serotonin-related genes and treatment responses to risperidone and perospirone.
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Tsutsumi A, Kanazawa T, Kikuyama H, Okugawa G, Uenishi H, Miyamoto T, Matsumoto N, Koh J, Shinosaki K, Kishimoto T, Yoneda H, and Kinoshita T
- Abstract
We investigated the possible association between genetic polymorphisms in the dopamine receptor and serotonin transporter genes and the responses of schizophrenic patients treated with either risperidone or perospirone. The subjects comprised 27 patients with schizophrenia who were clinically evaluated both before and after treatment. The genotyping of the polymorphisms of the dopamine D2 receptor gene (DRD2) (rs1801028 and rs6277), the dopamine D4 receptor gene (DRD4) (120-bp tandem repeats and rs1800955), and serotonin transporter gene (5HTT)(variable number of tandem repeats; VNTR) were performed using the real-time polymerase chain reaction and sequencing. In DRD2 and 5HTT-VNTR, there were no significant correlations between clinical response and polymorphism in the case of risperidone, and for perospirone treatment it was impossible to analyze the clinical evaluation due to the absence of genotype information. On the other hand, in DRD4 there were significant correlations in the two-factor interaction effect on the Positive and Negative Syndrome Scale (PANSS) between the two drugs [120-bp tandem repeat, p=0.003; rs1800955, p=0.043]. Although the small sample represents a serious limitation, these results suggest that variants in DRD4 are a predictor of whether treatment will be more effective with risperidone or with perospirone in individual patients.
- Published
- 2009
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41. Randomized clinical comparison of perospirone and risperidone in patients with schizophrenia: Kansai Psychiatric Multicenter Study.
- Author
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Okugawa G, Kato M, Wakeno M, Koh J, Morikawa M, Matsumoto N, Shinosaki K, Yoneda H, Kishimoto T, and Kinoshita T
- Subjects
- Adolescent, Adult, Aged, Antipsychotic Agents adverse effects, Basal Ganglia Diseases chemically induced, Female, Humans, Isoindoles adverse effects, Male, Middle Aged, Psychiatric Status Rating Scales statistics & numerical data, Risperidone adverse effects, Thiazoles adverse effects, Antipsychotic Agents therapeutic use, Isoindoles therapeutic use, Risperidone therapeutic use, Schizophrenia drug therapy, Schizophrenic Psychology, Thiazoles therapeutic use
- Abstract
Aim: Perospirone is classified as a second-generation antipsychotic agent for the treatment of schizophrenia. Perospirone binds with high affinity to serotonin 5-HT2A receptors and dopamine D2 receptors. There are no reports of clinical comparisons of perospirone and risperidone in multicenter studies. To clarify the clinical traits of perospirone in the treatment of schizophrenia, the clinical efficacies and side-effects of perospirone and risperidone were compared in a randomized clinical multicenter trial., Methods: Sixty-six schizophrenia patients were enrolled in the trial. The Positive and Negative Syndrome Scale (PANSS) total, positive, negative and general symptoms scores and Drug-Induced Extra-Pyramidal Symptoms Scale (DIEPSS) scores were investigated at 0, 4, 8 and 12 weeks., Results: Significant reductions in the PANSS total and subscale scores were observed in both the perospirone and risperidone groups, with no significant between-group differences at 4 and 12 weeks. Risperidone improved the total scores and overall psychopathologic symptom total scores more effectively than perospirone at week 8. There were no significant differences in the DIEPSS scores at 0, 4, 8 and 12 weeks between the perospirone and risperidone groups. The numbers of patients who dropped out did not differ between the perospirone and risperidone groups., Conclusions: Perospirone was as effective as risperidone against positive and negative symptoms in patients with schizophrenia. Both antipsychotic agents were equally well-tolerated.
- Published
- 2009
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42. Donepezil in the treatment of musical hallucinations.
- Author
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Ukai S, Yamamoto M, Tanaka M, Shinosaki K, and Takeda M
- Subjects
- Aged, 80 and over, Donepezil, Drug Therapy, Combination, Female, Hallucinations psychology, Hearing Disorders complications, Humans, Hallucinations drug therapy, Indans therapeutic use, Music psychology, Nootropic Agents therapeutic use, Piperidines therapeutic use
- Abstract
Musical hallucinations (MH) typically occur among elderly individuals and are associated with hearing impairment. The authors describe a patient with features of typical MH who was successfully treated with donepezil, a cholinesterase inhibitor, as a combination therapy and who has not shown any subsequent cognitive decline for approximately 5 years. The efficacy of donepezil in this patient indicates that age-dependent dysfunction of cholinergic neurons might be related to the development of MH.
- Published
- 2007
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43. Spatially filtered magnetoencephalographic analysis of cortical oscillatory changes in basic brain rhythms during the Japanese 'Shiritori' Word Generation Task.
- Author
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Yamamoto M, Ukai S, Shinosaki K, Ishii R, Kawaguchi S, Ogawa A, Mizuno-Matsumoto Y, Fujita N, Yoshimine T, and Takeda M
- Subjects
- Adult, Brain Mapping, Female, Functional Laterality physiology, Humans, Japan, Magnetic Resonance Imaging, Male, Task Performance and Analysis, Cortical Synchronization methods, Frontal Lobe physiology, Language, Magnetoencephalography, Reading, Temporal Lobe physiology
- Abstract
Background: 'Shiritori' (capping verses) is a traditional Japanese word generation game, and is very familiar to native Japanese speakers. The shiritori task is expected to more strongly activate temporal language-related regions than conventional word generation to letters because of its characteristic way to make cue letters., Objectives: The aim of this study was to examine the cortical oscillatory changes in basic brain rhythms during silently performing a shiritori task., Methods: Using synthetic aperture magnetometry (SAM) analysis of magnetoencephalography, we estimated the tomographic distributions of the statistically significant differences of the power in the alpha and beta frequency bands between the resting and the task periods., Results: Significant event-related desynchronization (ERD) in the 8- to 25-Hz band, thought to reflect neural activation, was localized within task-related cortical regions with left-side dominance. The significant ERDs were estimated in both the frontal and temporal language-related regions encompassing Broca's and Wernicke's areas, although previous neuroimaging studies using word generation to letters showed neural activation predominantly in frontal regions., Conclusions: Our results show the potential of SAM analysis for reliable brain mapping of language processing, and suggest that the shiritori task might be more suitable for examining the language-related network in the brain than conventional word generation to letters.
- Published
- 2006
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44. Evaluation of regional cerebral blood flow in fahr disease with schizophrenia-like psychosis: a case report.
- Author
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Shouyama M, Kitabata Y, Kaku T, and Shinosaki K
- Subjects
- Adult, Basal Ganglia Diseases diagnosis, Basal Ganglia Diseases physiopathology, Calcinosis diagnosis, Calcinosis physiopathology, Female, Humans, Magnetic Resonance Imaging, Psychotic Disorders diagnosis, Regional Blood Flow physiology, Schizophrenia diagnosis, Technetium, Telencephalon diagnostic imaging, Temporal Lobe diagnostic imaging, Temporal Lobe physiopathology, Tomography, Emission-Computed, Single-Photon, Tomography, X-Ray Computed, Cerebrovascular Circulation physiology, Psychotic Disorders physiopathology, Schizophrenia physiopathology, Telencephalon blood supply
- Abstract
We report the case of a patient with Fahr disease presenting with schizophrenia-like psychosis for whom a technetium Tc99 methyl cysteinate dimmer brain study was used to evaluate regional blood flow. A brain single photon-emission CT study showed increased cerebral blood flow to the bilateral temporal lobes. Such perfusion abnormalities may reflect psychotic symptoms, including auditory hallucinations and delusions, which suggests a disruption of the cortico-subcortical neural circuits in psychosis.
- Published
- 2005
45. Information processing flow and neural activations in the dorsolateral prefrontal cortex in the Stroop task in schizophrenic patients. A spatially filtered MEG analysis with high temporal and spatial resolution.
- Author
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Kawaguchi S, Ukai S, Shinosaki K, Ishii R, Yamamoto M, Ogawa A, Mizuno-Matsumoto Y, Fujita N, Yoshimine T, and Takeda M
- Subjects
- Adolescent, Adult, Brain Mapping, Demography, Female, Functional Laterality, Hallucinations pathology, Humans, Magnetic Resonance Imaging methods, Magnetoencephalography methods, Male, Mental Status Schedule, Pattern Recognition, Visual physiology, Photic Stimulation methods, Prefrontal Cortex pathology, Schizophrenia pathology, Time Factors, Hallucinations etiology, Mental Processes physiology, Prefrontal Cortex physiopathology, Schizophrenia physiopathology
- Abstract
Using a spatially filtered magnetoencephalography analysis (synthetic aperture magnetometry), we estimated neural activations in the Stroop task in nearly real time for schizophrenic patients with/without auditory hallucinations and for normal control subjects. In addition, auditory hallucinations were examined through the information processing flow of the brain neural network, including the frontal regions. One hundred unaveraged magnetoencephalography signals during the incongruent stimulus responses were analyzed with a time window of 200 ms in steps of 50 ms. In the 25-60-Hz band, cortical regions that showed significant current source density changes were examined for each time window. The three groups showed significantly decreased current source density, corresponding to neural activation, with temporal overlap along the fundamental cognitive information processing flow: sensory input system, executive control system, motor output system. Transient neural activations in the dorsolateral prefrontal cortex were bilateral with left-side dominancy for normal controls, left-lateralized for nonhallucinators and right-lateralized for hallucinators. Our results suggest that the dysfunction in the left dorsolateral prefrontal cortex was related to auditory hallucinations, while the information processing flow was unaffected in the schizophrenic subjects in the Stroop task., (Copyright (c) 2005 S. Karger AG, Basel.)
- Published
- 2005
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46. SAM(g2) analysis for detecting spike localization: a comparison with clinical symptoms and ECD analysis in an epileptic patient.
- Author
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Ukai S, Kawaguchi S, Ishii R, Yamamoto M, Ogawa A, Mizuno-Matsumoto Y, Robinson SE, Fujita N, Yoshimine T, Shinosaki K, and Takeda M
- Subjects
- Adult, Humans, Male, Temporal Lobe physiology, Action Potentials physiology, Epilepsy diagnosis, Epilepsy physiopathology, Magnetics, Magnetoencephalography methods
- Abstract
SAM(g2) analysis, a combination of synthetic aperture magnetometry (SAM) and excess kurtosis (g2) method, is a novel epilepsy analysis procedure based on a spatial filtering technique. By producing a three-dimensional image of the g2 values and superimposing them onto a patient's MR images, this analysis can automatically estimate spike localization from raw MEG epilepsy signals including spikes. The aim of this study is to examine SAM(g2) analysis using MEG signals of an epileptic patient, whose clinical symptoms of colored elementary visual auras had ceased in accordance with the changes of the estimated localizations of the equivalent current dipoles (ECDs) of the interictal spikes. His visual auras were experienced in 1997, while they ceased in 1999 with effective medication. The patient provided written informed consent for the experimental procedures. The MEG signals were recorded in 1997 and 1999, and were analyzed using both ECD and SAM(g2) analyses. For the MEG signals of 1997, ECD analysis estimated most of the interictal spikes in the right fusiform and inferior temporal gyri, which subserve human color processing. SAM(g2) analysis also estimated them in the same areas. For those of 1999, both ECD and SAM(g2) analyses estimated them in the right transverse gyrus of Heschl. As well as ECD analysis, SAM(g2) analysis successfully estimated the changes of the localizations of the interictal spikes in accordance with the changes of the patient's clinical symptoms, indicating that SAM(g2) analysis is useful for detection of interictal spike localization in epileptic patients.
- Published
- 2004
47. Slow repetitive transcranial magnetic stimulation increases somatosensory high-frequency oscillations in humans.
- Author
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Ogawa A, Ukai S, Shinosaki K, Yamamoto M, Kawaguchi S, Ishii R, and Takeda M
- Subjects
- Adult, Biological Clocks physiology, Depressive Disorder therapy, Evoked Potentials, Somatosensory physiology, Functional Laterality physiology, Humans, Interneurons physiology, Interneurons radiation effects, Myoclonus therapy, Neural Inhibition physiology, Neural Inhibition radiation effects, Neural Pathways physiology, Neural Pathways radiation effects, Somatosensory Cortex physiology, Transcranial Magnetic Stimulation, Biological Clocks radiation effects, Electric Stimulation Therapy, Electromagnetic Fields, Evoked Potentials, Somatosensory radiation effects, Somatosensory Cortex radiation effects
- Abstract
Repetitive transcranial magnetic stimulation (rTMS) has been proposed as a possible treatment for psychiatric and neurological disorders characterized by focal brain excitability, such as major depression and action myoclonus. However, the mechanism of modulating excitability by rTMS is unclear. We examined the changes in high frequency oscillations (HFOs) of somatosensory evoked potentials (SEPs) before and after slow rTMS over the right primary somatosensory cortex (0.5 Hz, 50 pulses, 80% motor threshold intensity). The HFOs, which represent a localized activity of intracortical inhibitory interneurons, were significantly increased after slow rTMS, while the SEPs were not changed. Our results suggest that slow rTMS affects cortical excitability by modulating the activity of the intracortical inhibitory interneurons beyond the time of the stimulation and that rTMS may have therapeutic effects on such disorders.
- Published
- 2004
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48. Interictal spikes in the fusiform and inferior temporal gyri of an epileptic patient with colored elementary visual auras: a 5-year longitudinal MEG ECD study.
- Author
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Kawaguchi S, Shinosaki K, Ukai S, Ishii R, Yamamoto M, Ogawa A, Fujita N, Yoshimine T, and Takeda M
- Subjects
- Adult, Brain Mapping, Disease Progression, Electrodes, Implanted, Functional Laterality, Humans, Longitudinal Studies, Magnetic Resonance Imaging, Male, Temporal Lobe anatomy & histology, Temporal Lobe pathology, Time Factors, Color Perception physiology, Electroencephalography, Epilepsy physiopathology, Magnetoencephalography methods, Parahippocampal Gyrus physiopathology, Temporal Lobe physiopathology
- Abstract
Using equivalent current dipole (ECD) analysis of magnetoencephalography (MEG), we examined the locations of interictal spikes for 5 years in an epileptic patient who had experienced colored elementary visual auras that gradually disappeared with medication. During the period that the patient frequently experienced colored elementary visual auras, six of nine spikes occurred in the right fusiform and inferior temporal gyri. As the frequency of the visual auras decreased, the spikes were widely distributed in the right hemisphere, but were not localized to these areas. After the visual auras ceased, six of seven spikes occurred in the right transverse gyrus of Heschl. These results suggest that colored elementary visual auras of epileptic-positive symptoms originate in the fusiform and inferior temporal gyri and that these regions are involved in human color processing. This is the first MEG study suggesting that the fusiform gyrus and the inferior temporal cortex are related to human color processing.
- Published
- 2003
- Full Text
- View/download PDF
49. Parallel distributed processing neuroimaging in the Stroop task using spatially filtered magnetoencephalography analysis.
- Author
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Ukai S, Shinosaki K, Ishii R, Ogawa A, Mizuno-Matsumoto Y, Inouye T, Hirabuki N, Yoshimine T, Robinson SE, and Takeda M
- Subjects
- Adult, Cortical Synchronization, Functional Laterality, Humans, Japan, Magnetoencephalography, Pattern Recognition, Visual physiology, Prefrontal Cortex anatomy & histology, Reading, Brain Mapping, Color Perception physiology, Prefrontal Cortex physiology
- Abstract
Parallel distributed processing neuroimaging in the Stroop color word interference task in five healthy subjects was studied. The total reaction time was set at 650 ms with a time window of 200 ms in steps of 50 ms. Spatially filtered magnetoencephalography analysis, as used in synthetic aperture magnetometry, was used. Neural activation began in the left posterior parietal-occipital area (150-250 ms post-stimulus), followed by the right prefrontal polar area (250-350 ms), the left dorsolateral prefrontal cortex (250-400 ms), and the mid- to lower- primary motor area (350-400 ms). Successive and temporally overlapping activation of various cortical regions were successfully estimated within a short 200 ms time interval, contrary to previous positron emission tomography and fMRI studies., (Copyright 2002 Elsevier Science Ireland Ltd.)
- Published
- 2002
- Full Text
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50. MEG study of long-term cortical reorganization of sensorimotor areas with respect to using chopsticks.
- Author
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Ishii R, Schulz M, Xiang J, Takeda M, Shinosaki K, Stuss DT, and Pantev C
- Subjects
- Adult, Asia, Europe, Fingers, Humans, Magnetics, Magnetoencephalography, Eating, Motor Cortex physiology, Motor Skills physiology, Movement physiology, Somatosensory Cortex physiology
- Abstract
The movements required to use chopsticks are overlearned and routine in Asians. Most non-Asians, on the other hand, typically have difficulty performing this unfamiliar manual activity, and have to focus their attention on the movements required to use chopsticks adequately. Using magnetoencephalography (MEG) we compared the cortical activation of highly trained Asian chopstick users to the activation of Europeans who only occasionally used chopsticks, while they performed the same tasks with chopsticks or a control task of simple tapping of the same fingers. The data were analyzed using the new method of synthetic aperture magnetometry (SAM). In Europeans there was a significantly higher ratio of spectral power in the higher gamma frequency band (60-80 Hz) over the sensorimotor area compared to the Asian subjects. From these results we conclude that the high gamma band activity in the sensorimotor area may reflect focused attention and functional reorganization of the cortical network with respect to sensorimotor experience.
- Published
- 2002
- Full Text
- View/download PDF
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