76 results on '"Shunichiro Ikeda"'
Search Results
2. Narrowing the Patient–Physician Gap Based on Self-Reporting and Monthly Hepatologist Feedback for Patients With Alcohol-Related Liver Disease: Interventional Pilot Study Using a Journaling Smartphone App
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Noriyo Yamashiki, Kyoko Kawabata, Miki Murata, Shunichiro Ikeda, Takako Fujimaki, Kanehiko Suwa, Toshihito Seki, Eiji Aramaki, and Makoto Naganuma
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Medicine - Abstract
BackgroundScreening and intervention for alcohol use disorders (AUDs) are recommended to improve the prognosis of patients with alcohol-related liver disease (ALD). Most patients’ smartphone app diaries record drinking behavior for self-monitoring. A smartphone app can be expected to also be helpful for physicians because it can provide rich patient information to hepatologists, leading to suitable feedback. We conducted this prospective pilot study to assess the use of a smartphone app as a journaling tool and as a self-report–based feedback source for patients with ALD. ObjectiveThe aims of this study were assessment of whether journaling (self-report) and self-report–based feedback can help patients maintain abstinence and improve liver function data. MethodsThis pilot study used a newly developed smartphone journaling app for patients, with input data that physicians can review. After patients with ALD were screened for harmful alcohol use, some were invited to use the smartphone journaling app for 8 weeks. Their self-reported alcohol intake, symptoms, and laboratory data were recorded at entry, week 4, and week 8. Biomarkers for alcohol use included gamma glutamyl transferase (GGT), percentage of carbohydrate-deficient transferrin to transferrin (%CDT), and GGT-CDT (GGT-CDT= 0.8 × ln[GGT] + 1.3 × ln[%CDT]). At each visit, their recorded data were reviewed by a hepatologist to evaluate changes in alcohol consumption and laboratory data. The relation between those outcomes and app usage was also investigated. ResultsOf 14 patients agreeing to participate, 10 completed an 8-week follow-up, with diary input rates between 44% and 100% of the expected days. Of the 14 patients, 2 withdrew from clinical follow-up, and 2 additional patients never used the smartphone journaling app. Using the physician’s view, a treating hepatologist gave feedback via comments to patients at each visit. Mean self-reported alcohol consumption dropped from baseline (100, SD 70 g) to week 4 (13, SD 25 g; P=.002) and remained lower at week 8 (13, SD 23 g; P=.007). During the study, 5 patients reported complete abstinence. No significant changes were found in mean GGT and mean %CDT alone, but the mean GGT-CDT combination dropped significantly from entry (5.2, SD 1.2) to the week 4 visit (4.8, SD 1.1; P=.02) and at week 8 (4.8, SD 1.0; P=.01). During the study period, decreases in mean total bilirubin (3.0, SD 2.4 mg/dL to 2.4, SD 1.9 mg/dL; P=.01) and increases in mean serum albumin (3.0, SD 0.9 g/dL to 3.3, SD 0.8 g/dL; P=.009) were recorded. ConclusionsThese pilot study findings revealed that a short-term intervention with a smartphone journaling app used by both patients and treatment-administering hepatologists was associated with reduced drinking and improved liver function. Trial RegistrationUMIN CTR UMIN000045285; http://tinyurl.com/yvvk38tj
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- 2023
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3. The shift changes of EEG microstate maps after a single session transcranial direct current stimulation in patients with depression
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Keiichiro Nishida, Shota Minami, Shunichiro Ikeda, Banri Tsukuda, Tomonari Yamne, Toshiyuki Shimizu, Masafumi Yoshimura, and Toshihiko Kinoshita
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Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Published
- 2023
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4. Changes of clinical symptoms in patients with new psychoactive substance (NPS)‐related disorders from fiscal year 2012 to 2014: A study in hospitals specializing in the treatment of addiction
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Daisuke Funada, Toshihiko Matsumoto, Yuko Tanibuchi, Yasunari Kawasoe, Satoru Sakakibara, Nobuya Naruse, Shunichiro Ikeda, Takashi Sunami, Takeo Muto, and Tetsuji Cho
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addiction ,government regulation ,new psychoactive substance ,psychiatric hospital ,substance‐related disorders ,Therapeutics. Pharmacology ,RM1-950 ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Abstract Aims The use of new psychoactive substances (NPS) has become increasingly widespread over the last decade, in Japan and internationally. NPS are associated with a range of increasingly serious clinical, public, and social issues. Political measures to ameliorate the effects of NPS in Japan have focused on tightening regulation rather than establishing treatment methods. The current study sought to compare the neuropsychiatric symptoms of patients with NPS‐related disorders across several years. We examined patients who attended specialized hospitals for treating addiction, to elucidate the impacts of legal measures to control NPS. Methods Subjects (n = 864) were patients with NPS‐related disorders who received medical treatment at eight specialized hospitals for treating addiction in Japan between April 2012 and March 2015. Clinical information was collected retrospectively from medical records. Results Among psychiatric symptoms, the ratio of hallucinations/delusions decreased over time across 3 years of study (first year vs second year vs third year: 40.1% vs 30.9% vs 31.7%, P = 0.037). Among neurological symptoms, the ratio of coma/syncope increased over the 3‐year period (7.8% vs 11.0% vs 17.0%, P = 0.002), as did the ratio of convulsions (2.8% vs 4.3% vs 9.7%, P = 0.001). Conclusion The symptoms associated with NPS were primarily psychiatric in the first year, while the prevalence of neurological symptoms increased each year. The risk of death and the severity of symptoms were greater in the third year compared with the first year, as regulation of NPS increased.
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- 2019
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5. Short-term meditation modulates EEG activity in subjects with post-traumatic residual disabilities
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Masahiro Hata, Noriyuki Hayashi, Ryouhei Ishii, Leonides Canuet, Roberto D. Pascual-Marqui, Yasunori Aoki, Shunichiro Ikeda, Toshiko Sakamoto, Masami Iwata, Keishin Kimura, Masao Iwase, Manabu Ikeda, and Toshinori Ito
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Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Objective: Neurophysiological changes related to meditation have recently attracted scientific attention. We aimed to detect changes in electroencephalography (EEG) parameters induced by a meditative intervention in subjects with post-traumatic residual disability (PTRD), which has been confirmed for effectiveness and safety in a previous study. This will allow us to estimate the objective effect of this intervention at the neurophysiological level. Methods: Ten subjects with PTRD were recruited and underwent psychological assessment and EEG recordings before and after the meditative intervention. Furthermore, 10 additional subjects were recruited as normal controls. Source current density as an EEG parameter was estimated by exact Low Resolution Electromagnetic Tomography (eLORETA). Comparisons of source current density in PTRD subjects after the meditative intervention with normal controls were investigated. Additionally, we compared source current density in PTRD subjects between before and after meditative intervention. Correlations between psychological assessments and source current density were also explored. Results: After meditative intervention, PTRD subjects exhibited increased gamma activity in the left inferior parietal lobule relative to normal controls. In addition, changes of delta activity in the right precuneus correlated with changes in the psychological score on role physical item, one of the quality of life scales reflecting the work or daily difficulty due to physical problems. Conclusions: These results show that the meditative intervention used in this study produces neurophysiological changes, in particular the modulation of oscillatory activity of the brain. Significance: Our meditative interventions might induce the neurophysiological changes associated with the improvement of psychological symptoms in the PTRD subjects. Keywords: EEG, Meditation, eLORETA, PTRD, Gamma band, Delta band
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- 2019
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6. Functional localization and effective connectivity of cortical theta and alpha oscillatory activity during an attention task
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Yuichi Kitaura, Keiichiro Nishida, Masafumi Yoshimura, Hiroshi Mii, Koji Katsura, Satsuki Ueda, Shunichiro Ikeda, Roberto D. Pascual-Marqui, Ryouhei Ishii, and Toshihiko Kinoshita
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Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Objectives: The aim of this paper is to investigate cortical electric neuronal activity as an indicator of brain function, in a mental arithmetic task that requires sustained attention, as compared to the resting state condition. The two questions of interest are the cortical localization of different oscillatory activities, and the directional effective flow of oscillatory activity between regions of interest, in the task condition compared to resting state. In particular, theta and alpha activity are of interest here, due to their important role in attention processing. Methods: We adapted mental arithmetic as an attention ask in this study. Eyes closed 61-channel EEG was recorded in 14 participants during resting and in a mental arithmetic task (“serial sevens subtraction”). Functional localization and connectivity analyses were based on cortical signals of electric neuronal activity estimated with sLORETA (standardized low resolution electromagnetic tomography). Functional localization was based on the comparison of the cortical distributions of the generators of oscillatory activity between task and resting conditions. Assessment of effective connectivity was based on the iCoh (isolated effective coherence) method, which provides an appropriate frequency decomposition of the directional flow of oscillatory activity between brain regions. Nine regions of interest comprising nodes from the dorsal and ventral attention networks were selected for the connectivity analysis. Results: Cortical spectral density distribution comparing task minus rest showed significant activity increase in medial prefrontal areas and decreased activity in left parietal lobe for the theta band, and decreased activity in parietal-occipital regions for the alpha1 band. At a global level, connections among right hemispheric nodes were predominantly decreased during the task condition, while connections among left hemispheric nodes were predominantly increased. At more detailed level, decreased flow from right inferior frontal gyrus to anterior cingulate cortex for theta, and low and high alpha oscillations, and increased feedback (bidirectional flow) between left superior temporal gyrus and left inferior frontal gyrus, were observed during the arithmetic task. Conclusions: Task related medial prefrontal increase in theta oscillations possibly corresponds to frontal midline theta, while parietal decreased alpha1 activity indicates the active role of this region in the numerical task. Task related decrease of intracortical right hemispheric connectivity support the notion that these nodes need to disengage from one another in order to not interfere with the ongoing numerical processing. The bidirectional feedback between left frontal-temporal-parietal regions in the arithmetic task is very likely to be related to attention network working memory function. Significance: The methods of analysis and the results presented here will hopefully contribute to clarify the roles of the different EEG oscillations during sustained attention, both in terms of their functional localization and in terms of how they integrate brain function by supporting information flow between different cortical regions. The methodology presented here might be clinically relevant in evaluating abnormal attention function. Keywords: Quantitative EEG, sLORETA, iCoh, Directional connectivity, Frontal midline theta, Attention network, Mental arithmetic, Fronto-parietal network, Directional flow, Attention task, Granger causality
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- 2017
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7. Pre-stimulus Brain Activity Is Associated With State-Anxiety Changes During Single-Session Transcranial Direct Current Stimulation
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Keiichiro Nishida, Yosuke Koshikawa, Yosuke Morishima, Masafumi Yoshimura, Koji Katsura, Satsuki Ueda, Shunichiro Ikeda, Ryouhei Ishii, Roberto Pascual-Marqui, and Toshihiko Kinoshita
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transcranial direct current stimulation ,left dorsolateral prefrontal cortex ,dorsomedial prefrontal cortex ,anterior cingulate ,anxiety ,depression ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Transcranial direct current stimulation is a promising neuromodulation method for treating depression. However, compared with pharmacological treatment, previous studies have reported that a relatively limited proportion of patients respond to tDCS treatment. In addition, the neurophysiological mechanisms underlying tDCS treatment remain unclear, making it difficult to identify response predictors for tDCS treatment based on neurophysiological function. Because treatment effects are achieved by repetitive application of tDCS, studying the immediate effects of tDCS in depressive patients could extend understanding of its treatment mechanisms. However, immediate changes in a single session of tDCS are not well documented. Thus, in the current study, we focused on the immediate impact of tDCS and its association with pre-stimulus brain activity. To address this question, we applied anodal tDCS to the left dorsolateral prefrontal cortex (DLPFC) or dorsomedial prefrontal cortex (DMPFC) in 14 patients with major depressive disorder (MDD) and 19 healthy controls (HCs), at an intensity of 1.0 mA for 20 min in a single session. To evaluate anxiety, the state trait anxiety inventory was completed before and after tDCS. We recorded resting electroencephalography before tDCS, and calculated electrical neuronal activity in the theta and alpha frequency bands using standardized low-resolution electromagnetic tomography. We found that, during application of left DLPFC tDCS to patients with MDD, the anxiety reduction effect of tDCS was related to higher baseline theta-band activity in the rostral anterior cingulate cortex (rACC) and no medication with benzodiazepine used as hypnotic. For DMPFC stimulation in MDD, the anxiety reduction effect was associated with lower baseline alpha-band activity in the left inferior parietal lobule. In contrast, in HCs, the anxiety reduction effect was associated with higher baseline alpha activity in the precuneus during DMPFC stimulation. The current results suggest that the association between pre-tDCS brain activity and the anxiety reduction effect of tDCS depends on psychopathology (depressed or non-depressed) as well as the site of stimulation (DMPFC or left DLPFC) and insomnia. Furthermore, the results suggest that tDCS response might be associated with baseline resting state electrophysiological neural activity.
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- 2019
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8. A Switch in the Dynamics of Intra-Platelet VEGF-A from Cancer to the Later Phase of Liver Regeneration after Partial Hepatectomy in Humans.
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Bibek Aryal, Toshiaki Shimizu, Jun Kadono, Akira Furoi, Teruo Komokata, Maki Inoue, Shunichiro Ikeda, Yoshihiko Fukukura, Masatoshi Nakamura, Munekazu Yamakuchi, Teruto Hashiguchi, and Yutaka Imoto
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Medicine ,Science - Abstract
Liver regeneration (LR) involves an early inductive phase characterized by the proliferation of hepatocytes, and a delayed angiogenic phase distinguished by the expansion of non-parenchymal compartment. The interest in understanding the mechanism of LR has lately shifted from the proliferation and growth of parenchymal cells to vascular remodeling during LR. Angiogenesis accompanied by LR exerts a pivotal role to accomplish the process. Vascular endothelial growth factor (VEGF) has been elucidated as the most dynamic regulator of angiogenesis. From this perspective, platelet derived/Intra-platelet (IP) VEGF-A should be associated with LR.Thirty-seven patients diagnosed with hepatocellular carcinoma and undergoing partial hepatectomy (PH) were enrolled in the study. Serum and IP VEGF-A was monitored preoperatively and at four weeks of PH. Liver volumetry was determined on computer models derived from computed tomography (CT) scan.Serum and IP VEGF-A was significantly elevated at four weeks of PH. Preoperative IP VEGF-A was higher in patients with advanced cancer and vascular invasion. Postoperative IP VEGF-A was higher after major liver resection. There was a statistically significant correlation between postoperative IP VEGF-A and the future remnant liver volume. Moreover, the soluble vascular endothelial growth factor receptor-1 (sVEGFR1) was distinctly down-regulated suggesting a fine-tuned angiogenesis at the later phase of LR.IP VEGF-A is overexpressed during later phase of LR suggesting its implications in inducing angiogenesis during LR.
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- 2016
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9. Resting-state EEG source localization and functional connectivity in schizophrenia-like psychosis of epilepsy.
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Leonides Canuet, Ryouhei Ishii, Roberto D Pascual-Marqui, Masao Iwase, Ryu Kurimoto, Yasunori Aoki, Shunichiro Ikeda, Hidetoshi Takahashi, Takayuki Nakahachi, and Masatoshi Takeda
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Medicine ,Science - Abstract
BACKGROUND: It is unclear whether, like in schizophrenia, psychosis-related disruption in connectivity between certain regions, as an index of intrinsic functional disintegration, occurs in schizophrenia-like psychosis of epilepsy (SLPE). In this study, we sought to determine abnormal patterns of resting-state EEG oscillations and functional connectivity in patients with SLPE, compared with nonpsychotic epilepsy patients, and to assess correlations with psychopathological deficits. METHODOLOGY/PRINCIPAL FINDINGS: Resting EEG was recorded in 21 patients with focal epilepsy and SLPE and in 21 clinically-matched non-psychotic epilepsy controls. Source current density and functional connectivity were determined using eLORETA software. For connectivity analysis, a novel nonlinear connectivity measure called "lagged phase synchronization" was used. We found increased theta oscillations in regions involved in the default mode network (DMN), namely the medial and lateral parietal cortex bilaterally in the psychotic patients relative to their nonpsychotic counterparts. In addition, patients with psychosis had increased beta temporo-prefrontal connectivity in the hemisphere with predominant seizure focus. This functional connectivity in temporo-prefrontal circuits correlated with positive symptoms. Additionally, there was increased interhemispheric phase synchronization between the auditory cortex of the affected temporal lobe and the Broca's area correlating with auditory hallucination scores. CONCLUSIONS/SIGNIFICANCE: In addition to dysfunction of parietal regions that are part of the DMN, resting-state disrupted connectivity of the medial temporal cortex with prefrontal areas that are either involved in the DMN or implicated in psychopathological dysfunction may be critical to schizophrenia-like psychosis, especially in individuals with temporal lobe epilepsy. This suggests that DMN deficits might be a core neurobiological feature of the disorder, and that abnormalities in theta oscillations and beta phase synchronization represent the underlying neural activity.
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- 2011
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10. Precise Discrimination for Multiple Etiologies of Dementia Cases Based on Deep Learning with Electroencephalography
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Masahiro Hata, Yusuke Watanabe, Takumi Tanaka, Kimihisa Awata, Yuki Miyazaki, Ryohei Fukuma, Daiki Taomoto, Yuto Satake, Takashi Suehiro, Hideki Kanemoto, Kenji Yoshiyama, Masao Iwase, Shunichiro Ikeda, Keiichiro Nishida, Yoshiteru Takekita, Masafumi Yoshimura, Ryouhei Ishii, Hiroaki Kazui, Tatsuya Harada, Haruhiko Kishima, Manabu Ikeda, and Takufumi Yanagisawa
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Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Biological Psychiatry - Abstract
Introduction: It is critical to develop accurate and universally available biomarkers for dementia diseases to appropriately deal with the dementia problems under world-wide rapid increasing of patients with dementia. In this sense, electroencephalography (EEG) has been utilized as a promising examination to screen and assist in diagnosing dementia, with advantages of sensitiveness to neural functions, inexpensiveness, and high availability. Moreover, the algorithm-based deep learning can expand EEG applicability, yielding accurate and automatic classification easily applied even in general hospitals without any research specialist. Methods: We utilized a novel deep neural network, with which high accuracy of discrimination was archived in neurological disorders in the previous study. Based on this network, we analyzed EEG data of healthy volunteers (HVs, N = 55), patients with Alzheimer’s disease (AD, N = 101), dementia with Lewy bodies (DLB, N = 75), and idiopathic normal pressure hydrocephalus (iNPH, N = 60) to evaluate the discriminative accuracy of these diseases. Results: High discriminative accuracies were archived between HV and patients with dementia, yielding 81.7% (vs. AD), 93.9% (vs. DLB), 93.1% (vs. iNPH), and 87.7% (vs. AD, DLB, and iNPH). Conclusion: This study revealed that the EEG data of patients with dementia were successfully discriminated from HVs based on a novel deep learning algorithm, which could be useful for automatic screening and assisting diagnosis of dementia diseases.
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- 2023
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11. Normalized power variance change between pre-ictal and ictal phase of an epilepsy patient using NAT analysis: A case study.
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Yasunori Aoki, Ryouhei Ishii, Masao Iwase, Shunichiro Ikeda, Masahiro Hata, Leonides Canuet, Kaoru Imajo, Mieko Tanaka, Haruyasu Matsuzaki, Toshimitsu Musha, and Masatoshi Takeda
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- 2013
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12. Non-parametric permutation thresholding for adaptive nonlinear beamformer analysis on MEG revealed oscillatory neuronal dynamics in human brain.
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Ryouhei Ishii, Leonides Canuet, Yasunori Aoki, Shunichiro Ikeda, Masahiro Hata, Masao Iwase, and Masatoshi Takeda
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- 2013
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13. Narrowing the patient–specialist gap: Pilot study of a diary smartphone-app for patients with alcohol-related liver disease (Preprint)
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Noriyo Yamashiki, Kyoko Kawabata, Miki Murata, Shunichiro Ikeda, Takako Fujimaki, Kanehiko Suwa, Toshihito Seki, Eiji Aramaki, and Makoto Naganuma
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BACKGROUND Screening and intervention for alcohol use disorders (AUD) are recommended to improve alcohol-related liver disease (ALD) patient prognosis. Most patients’ smartphone application (app) diaries record drinking behavior for self-monitoring, but such data might be useful by treating teams. OBJECTIVE Aims of this study were to assess the use of a smartphone-app as a recording diary and to evaluate the usability of this tool for ALD patients. METHODS This pilot study used a newly developed smartphone journaling app for patients, with input data that physicians can review. After ALD patients were screened for harmful alcohol use, some were invited to use the smartphone journaling app for 8 weeks. Their self-reported alcohol intake, symptoms, and laboratory data were recorded at entry, week 4, and week 8. Later, their recorded data were reviewed by outpatient clinic physicians to evaluate changes in alcohol consumption, laboratory data, and app usage. RESULTS Of 14 patients agreeing to participate, 10 completed 8-week follow-up with diary input rates between 44% and 100% of expected days. Two withdrew from clinical follow-up. Two others never used the smartphone journaling app. Using the doctor’s view, a treating physician gave feedback comments to patients at each visit. Self-reported alcohol consumption dropped from baseline (100 ±70 g) to week 4 (13±25 g, p CONCLUSIONS These pilot study findings revealed that the smartphone journaling app used by both patients and treating physicians produced short-term reduced drinking and enhanced patient motivation.
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- 2022
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14. Induced oscillatory responses during the Sternberg's visual memory task in patients with Alzheimer's disease and mild cognitive impairment.
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Ryu Kurimoto, Ryouhei Ishii, Leonides Canuet, Koji Ikezawa, Masao Iwase, Michiyo Azechi, Yasunori Aoki, Shunichiro Ikeda, Tetsuhiko Yoshida, Hidetoshi Takahashi, Takayuki Nakahachi, Hiroaki Kazui, and Masatoshi Takeda
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- 2012
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15. Association between the Rostral Anterior Cingulate Cortex and Anterior Insula in the Salience Network on Response to Antidepressants in Major Depressive Disorder as Revealed by Isolated Effective Coherence
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Shota Minami, Masaki Kato, Shunichiro Ikeda, Masafumi Yoshimura, Satsuki Ueda, Yosuke Koshikawa, Yoshiteru Takekita, Toshihiko Kinoshita, and Keiichiro Nishida
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Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Biological Psychiatry - Abstract
Introduction: Functional connectivity is attracting increasing attention for understanding the pathophysiology of depression and predicting the therapeutic efficacy of antidepressants. In this study, we evaluated effective connectivity using isolated effective coherence (iCoh), an effective functional connectivity analysis method developed from low-resolution brain electromagnetic tomography (LORETA) and estimated its practical usefulness for predicting the reaction to antidepressants in theta and alpha band iCoh values. Methods: We enrolled 25 participants from a depression treatment randomized study (the GUNDAM study) in which electroencephalography was performed before treatment. We conducted iCoh between the rostral anterior cingulate cortex (rACC) and anterior insula (AI), which are associated with the salience network. The patients were divided into responder and nonresponder groups at 4 weeks after the start of treatment, and iCoh values were compared between the two groups. Additionally, the sensitivity and specificity of iCoh were calculated using the receiver-operating characteristic (ROC) curve. Results: The Mann-Whitney U test showed significantly weaker connectivity flow from the rACC to the left AI in the alpha band in the responder group. The ROC curve for the connectivity flow from the rACC to the left AI in the alpha band showed 82% sensitivity and 86% specificity. Discussion/Conclusion: These findings suggest the pathological importance of effective connectivity flow from the rACC to the left AI in the alpha and theta bands and suggest its usefulness as a biomarker to distinguish responders to antidepressants.
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- 2022
16. Precise Discrimination for Multiple Underlying Pathologies of Dementia Cases Based on Deep-Learning with Electroencephalography
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Tatsuya Harada, Yusuke Watanabe, Shunichiro Ikeda, Kenji Yoshiyama, Hiroaki Kazui, Yoshiteru Takekita, Kimihisa Awata, Masahiro Hata, Yuto Satake, Hideki Kanemoto, Ryohei Fukuma, Keiichiro Nishida, Manabu Ikeda, Yuki Miyazaki, Takumi Tanaka, Daiki Taomoto, Ryouhei Ishii, Masao Iwase, Takashi Suehiro, Takufumi Yanagisawa, Masafumi Yoshimura, and Haruhiko Kishima
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Text mining ,medicine.diagnostic_test ,business.industry ,Deep learning ,mental disorders ,medicine ,Dementia ,Artificial intelligence ,Electroencephalography ,medicine.disease ,Psychology ,business ,Cognitive psychology - Abstract
Background: Developing accurate and universally available biomarkers for dementia diseases is demanded under world-wide rapid increasing of patients with dementia. Electroencephalogram (EEG) offers promising examinations due to their inexpensiveness, high availability, and sensitiveness to neural functions. EEG applicability can be expanded by deep-learning.Methods: We analyzed EEG signals based on novel deep neural network in healthy volunteers (HV, N=55), patients with Alzheimer's disease (AD, N=101), dementia with Lewy bodies (DLB, N=75), and idiopathic normal pressure hydrocephalus (iNPH, N=60) to evaluate the discriminative accuracy of these diseases.Results: High discriminative accuracies were archived between HV and patients with dementia, yielding 81.7 %(vs AD), 93.9% (vs DLB), and 93.1% (vs iNPH).Conclusions: This study revealed that the EEG data of patients with dementia were successfully discriminated from healthy volunteers based on deep learning and could produce a new purpose of EEG measurement in screening for dementia diseases.
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- 2021
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17. Short-term meditation modulates EEG activity in subjects with post-traumatic residual disabilities
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Shunichiro Ikeda, Manabu Ikeda, Masahiro Hata, Leonides Canuet, Ryouhei Ishii, Noriyuki Hayashi, Masami Iwata, Toshiko Sakamoto, Masao Iwase, Roberto D. Pascual-Marqui, Yasunori Aoki, Keishin Kimura, Toshinori Ito, University of Zurich, and Ishii, Ryouhei
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Delta band ,medicine.medical_specialty ,Neurology ,media_common.quotation_subject ,Clinical Neurology ,Psychological intervention ,eLORETA ,PTRD ,610 Medicine & health ,Audiology ,Electroencephalography ,lcsh:RC321-571 ,Gamma band ,03 medical and health sciences ,2737 Physiology (medical) ,0302 clinical medicine ,Physiology (medical) ,Intervention (counseling) ,medicine ,Psychological testing ,EEG ,Meditation ,skin and connective tissue diseases ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,media_common ,medicine.diagnostic_test ,business.industry ,030208 emergency & critical care medicine ,Neurophysiology ,10074 The KEY Institute for Brain-Mind Research ,2728 Neurology (clinical) ,Eeg activity ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,2808 Neurology ,Clinical and Research Article ,sense organs ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
Highlights • We aimed to detect EEG changes induced by meditative interventions in PTRD subjects. • PTRD subjects exhibited increased gamma activity in the IPL relative to controls. • Changes of delta activity in the precuneus correlated with changes of the QOL scale., Objective Neurophysiological changes related to meditation have recently attracted scientific attention. We aimed to detect changes in electroencephalography (EEG) parameters induced by a meditative intervention in subjects with post-traumatic residual disability (PTRD), which has been confirmed for effectiveness and safety in a previous study. This will allow us to estimate the objective effect of this intervention at the neurophysiological level. Methods Ten subjects with PTRD were recruited and underwent psychological assessment and EEG recordings before and after the meditative intervention. Furthermore, 10 additional subjects were recruited as normal controls. Source current density as an EEG parameter was estimated by exact Low Resolution Electromagnetic Tomography (eLORETA). Comparisons of source current density in PTRD subjects after the meditative intervention with normal controls were investigated. Additionally, we compared source current density in PTRD subjects between before and after meditative intervention. Correlations between psychological assessments and source current density were also explored. Results After meditative intervention, PTRD subjects exhibited increased gamma activity in the left inferior parietal lobule relative to normal controls. In addition, changes of delta activity in the right precuneus correlated with changes in the psychological score on role physical item, one of the quality of life scales reflecting the work or daily difficulty due to physical problems. Conclusions These results show that the meditative intervention used in this study produces neurophysiological changes, in particular the modulation of oscillatory activity of the brain. Significance Our meditative interventions might induce the neurophysiological changes associated with the improvement of psychological symptoms in the PTRD subjects.
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- 2019
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18. Alpha frequency rTMS modulates theta lagged nonlinear connectivity in dorsal attention network
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Reza Kazemi, Zahra Nasiri, Shunichiro Ikeda, Ryouhei Ishii, Sanaz Khomami, Abed L. Hadipour, Solmaz Lotfollahzadeh, Shouka Dehghan, and Reza Rostami
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0301 basic medicine ,Adult ,Male ,medicine.medical_treatment ,Alpha (ethology) ,Prefrontal Cortex ,Electroencephalography ,behavioral disciplines and activities ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Task-positive network ,mental disorders ,medicine ,Humans ,Attention ,Default mode network ,medicine.diagnostic_test ,Postcentral gyrus ,General Neuroscience ,Inferior parietal lobule ,Transcranial Magnetic Stimulation ,Transcranial magnetic stimulation ,Dorsolateral prefrontal cortex ,Alpha Rhythm ,030104 developmental biology ,medicine.anatomical_structure ,Nonlinear Dynamics ,Female ,Nerve Net ,Psychology ,Neuroscience ,psychological phenomena and processes ,030217 neurology & neurosurgery ,Psychomotor Performance - Abstract
Dorsolateral prefrontal cortex (DLPFC) is a key structure in dorsal attention network (DAN) that facilitates sustained attention by modulating activity in task related and unrelated regions of the brain. Alpha and theta frequency bands enhance connectivity among different parts of the attention network and these connections are facilitated by long-range nonlinear connectivity in theta and alpha frequency bands. This study is an investigation of the behavioral and electrophysiological effects of alpha and theta frequency repetitive transcranial magnetic stimulation (rTMS) over RDLPFC. 20 healthy participants were randomly assigned to two groups of theta (n = 11, f = 6 Hz) and alpha (n = 9, f = 10 Hz) rTMS. Electroencephalogram (EEG) was recorded before and after each session while resting and performing tasks. Current source density (CSD) and functional connectivity (FC) in DAN and default mode network (DMN) and their correlations with rapid visual information processing task (RVIP) scores were calculated . Alpha frequency rTMS resulted in significant changes in RVIP scores. Active theta rTMS caused an increase in CSD in Postcentral gyrus and active alpha rTMS resulted in significant CSD changes in inferior parietal lobule (IPL). Theta lagged nonlinear connectivity was mudulated by alpha rTMSand FC changes were observed in DAN and DMN. Positive correlations were observed between DAN regions and RVIP scores in the alpha rTMS group. Increased activity in theta frequency band in left aPFC and left DLPFC correlated positively with higher total hits in RVIP. This study showed for the first time that theta and alpha frequency rTMS are able to modulate FC in DAN and DMN in a way that results in better performance in a sustained attention task.
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- 2020
19. Hyperactivation of the Frontal Control Network Revealed by Symptom Provocation in Obsessive-Compulsive Disorder Using EEG Microstate and sLORETA Analyses
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Toshiaki Isotani, Hiroshi Mii, Shunichiro Ikeda, Satsuki Ueda, Y. Kitaura, Roberto D. Pascual-Marqui, Toshihiko Kinoshita, Keiichiro Nishida, Koji Katsura, Yukiko Saito, Masafumi Yoshimura, and Shota Minami
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Adult ,Male ,Obsessive-Compulsive Disorder ,medicine.medical_specialty ,Rest ,Symptom provocation ,Electroencephalography ,Audiology ,behavioral disciplines and activities ,03 medical and health sciences ,0302 clinical medicine ,Ministate ,Neural Pathways ,Control network ,Humans ,Medicine ,Pathological ,Biological Psychiatry ,Cerebral Cortex ,Resting state fMRI ,medicine.diagnostic_test ,Hyperactivation ,business.industry ,Signal Processing, Computer-Assisted ,030227 psychiatry ,Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Imagination ,Female ,Biological psychiatry ,business ,030217 neurology & neurosurgery - Abstract
The aim of this study was to investigate the changes of brain electric field induced by symptom provocation in patients with obsessive-compulsive disorder (OCD) in comparison to healthy controls in the resting state. For this purpose, EEG recordings in conditions of initial rest, clean control, symptom provocation by imaginal exposure, and final rest were used for computing spatiotemporal activity characteristics based on microstate segmentation. Within-group comparisons were significant for the symptom provocation condition: OCD showed high global field power (GFP) and transition rates into a medial frontal microstate, whereas healthy controls showed high frequency of occurrence and high percent of dwelling time for a medial occipitoparietal microstate. Between-group comparisons demonstrated significantly lower GFP and dwelling time for the medial occipitoparietal microstate in OCD in several conditions including initial rest and symptom provocation. In addition, OCD compared to healthy controls showed significant instability of the medial occipitoparietal microstate, with high preference for transitions into the medial frontal microstate. In conclusion, during rest and symptom provocation, OCD patients make preferential use of a medial frontal brain network, with concomitant reduction of use of a medial occipitoparietal network, as shown by dwelling times, explained variance, and dynamic transition rates. These findings support the idea of a possible biological marker for OCD, which might correspond to pathological hyperactivation of the frontal control network.
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- 2018
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20. Healthy and Pathological Brain Aging: From the Perspective of Oscillations, Functional Connectivity, and Signal Complexity
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Masahiro Hata, Keiichiro Nishida, Leonides Canuet, Shunichiro Ikeda, Ryouhei Ishii, Manabu Ikeda, Yasunori Aoki, and Masao Iwase
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0301 basic medicine ,Aging ,Brain activity and meditation ,Motor Activity ,Electroencephalography ,03 medical and health sciences ,Cognition ,0302 clinical medicine ,Neuroimaging ,Event-related potential ,Neural Pathways ,medicine ,Humans ,Biological Psychiatry ,medicine.diagnostic_test ,Resting state fMRI ,business.industry ,Brain ,Magnetoencephalography ,Brain Waves ,Psychiatry and Mental health ,030104 developmental biology ,Neuropsychology and Physiological Psychology ,Functional magnetic resonance imaging ,business ,Neuroscience ,Neurocognitive ,030217 neurology & neurosurgery - Abstract
Healthy aging is associated with impairment in cognitive information processing. Several neuroimaging methods such as functional magnetic resonance imaging, positron emission tomography and near-infrared spectroscopy have been used to explore healthy and pathological aging by relying on hemodynamic or metabolic changes that occur in response to brain activity. Since electroencephalography (EEG) and magnetoencephalography (MEG) are able to measure neural activity directly with a high temporal resolution of milliseconds, these neurophysiological techniques are particularly important to investigate the dynamics of brain activity underlying neurocognitive aging. It is well known that age is a major risk factor for Alzheimer’s disease (AD), and that synaptic dysfunction represents an early sign of this disease associated with hallmark neuropathological findings. However, the neurophysiological mechanisms underlying AD are not fully elucidated. This review addresses healthy and pathological brain aging from a neurophysiological perspective, focusing on oscillatory activity changes during the resting state, event-related potentials and stimulus-induced oscillatory responses during cognitive or motor tasks, functional connectivity between brain regions, and changes in signal complexity. We also highlight the accumulating evidence on age-related EEG/MEG changes and biological markers of brain neurodegeneration, including genetic factors, structural abnormalities on magnetic resonance images, and the biochemical changes associated with Aβ deposition and tau pathology.
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- 2017
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21. Pre-stimulus Brain Activity Is Associated With State-Anxiety Changes During Single-Session Transcranial Direct Current Stimulation
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Roberto D. Pascual-Marqui, Toshihiko Kinoshita, Masafumi Yoshimura, Yosuke Koshikawa, Satsuki Ueda, Yosuke Morishima, Ryouhei Ishii, Keiichiro Nishida, Koji Katsura, Shunichiro Ikeda, University of Zurich, and Nishida, Keiichiro
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medicine.medical_specialty ,Brain activity and meditation ,medicine.medical_treatment ,Precuneus ,610 Medicine & health ,Electroencephalography ,Audiology ,050105 experimental psychology ,lcsh:RC321-571 ,3206 Neuropsychology and Physiological Psychology ,dorsomedial prefrontal cortex ,03 medical and health sciences ,2738 Psychiatry and Mental Health ,Behavioral Neuroscience ,0302 clinical medicine ,2802 Behavioral Neuroscience ,medicine ,0501 psychology and cognitive sciences ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Anterior cingulate cortex ,Biological Psychiatry ,Original Research ,anterior cingulate ,Transcranial direct-current stimulation ,Resting state fMRI ,medicine.diagnostic_test ,business.industry ,05 social sciences ,anxiety ,10074 The KEY Institute for Brain-Mind Research ,Psychiatry and Mental health ,left dorsolateral prefrontal cortex ,medicine.anatomical_structure ,Neuropsychology and Physiological Psychology ,Neurology ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,2808 Neurology ,depression ,Anxiety ,medicine.symptom ,transcranial direct current stimulation ,business ,2803 Biological Psychiatry ,030217 neurology & neurosurgery ,State-Trait Anxiety Inventory ,Neuroscience - Abstract
Transcranial direct current stimulation is a promising neuromodulation method for treating depression. However, compared with pharmacological treatment, previous studies have reported that a relatively limited proportion of patients respond to tDCS treatment. In addition, the neurophysiological mechanisms underlying tDCS treatment remain unclear, making it difficult to identify response predictors for tDCS treatment based on neurophysiological function. Because treatment effects are achieved by repetitive application of tDCS, studying the immediate effects of tDCS in depressive patients could extend understanding of its treatment mechanisms. However, immediate changes in a single session of tDCS are not well documented. Thus, in the current study, we focused on the immediate impact of tDCS and its association with pre-stimulus brain activity. To address this question, we applied anodal tDCS to the left dorsolateral prefrontal cortex (DLPFC) or dorsomedial prefrontal cortex (DMPFC) in 14 patients with major depressive disorder (MDD) and 19 healthy controls (HCs), at an intensity of 1.0 mA for 20 min in a single session. To evaluate anxiety, the state trait anxiety inventory was completed before and after tDCS. We recorded resting electroencephalography before tDCS, and calculated electrical neuronal activity in the theta and alpha frequency bands using standardized low-resolution electromagnetic tomography. We found that, during application of left DLPFC tDCS to patients with MDD, the anxiety reduction effect of tDCS was related to higher baseline theta-band activity in the rostral anterior cingulate cortex (rACC) and no medication with benzodiazepine used as hypnotic. For DMPFC stimulation in MDD, the anxiety reduction effect was associated with lower baseline alpha-band activity in the left inferior parietal lobule. In contrast, in HCs, the anxiety reduction effect was associated with higher baseline alpha activity in the precuneus during DMPFC stimulation. The current results suggest that the association between pre-tDCS brain activity and the anxiety reduction effect of tDCS depends on psychopathology (depressed or non-depressed) as well as the site of stimulation (DMPFC or left DLPFC) and insomnia. Furthermore, the results suggest that tDCS response might be associated with baseline resting state electrophysiological neural activity.
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- 2019
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22. The correlation between baseline prestimulus brain activity and anxiety change in single-session transcranial Direct Current Stimulation
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K. Kouji, Satsuki Ueda, Masafumi Yoshimura, Toshihiko Kinoshita, Roberto D. Pascual-Marqui, Yosuke Koshikawa, Shunichiro Ikeda, Keiichiro Nishida, and Ryouhei Ishii
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medicine.medical_specialty ,Transcranial direct-current stimulation ,business.industry ,Brain activity and meditation ,General Neuroscience ,medicine.medical_treatment ,Biophysics ,Audiology ,lcsh:RC321-571 ,Correlation ,medicine ,Anxiety ,Neurology (clinical) ,medicine.symptom ,Baseline (configuration management) ,business ,Single session ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry - Published
- 2019
23. Cerebrospinal Fluid Biomarkers of Alzheimer’s Disease Correlate With Electroencephalography Parameters Assessed by Exact Low-Resolution Electromagnetic Tomography (eLORETA)
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Yasunori Aoki, Masahiro Hata, Hideki Kanemoto, Leonides Canuet, Toshihisa Tanaka, Shunichiro Ikeda, Roberto D. Pascual-Marqui, Shunsuke Sato, Masao Iwase, Hiroaki Kazui, Kenji Yoshiyama, Yukiko Suzuki, Ryouhei Ishii, University of Zurich, and Ishii, R
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Male ,Pathology ,medicine.medical_specialty ,Amyloid beta ,610 Medicine & health ,Disease ,Electroencephalography ,050105 experimental psychology ,03 medical and health sciences ,0302 clinical medicine ,Cerebrospinal fluid ,Alzheimer Disease ,medicine ,Humans ,0501 psychology and cognitive sciences ,Aged ,Aged, 80 and over ,biology ,medicine.diagnostic_test ,Low resolution ,05 social sciences ,Brain ,General Medicine ,Middle Aged ,Neurophysiology ,medicine.disease ,10074 The KEY Institute for Brain-Mind Research ,2728 Neurology (clinical) ,Neurology ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,2808 Neurology ,biology.protein ,Female ,Neurology (clinical) ,Tomography ,Alzheimer's disease ,Tomography, X-Ray Computed ,Psychology ,Electromagnetic Phenomena ,Biomarkers ,030217 neurology & neurosurgery - Abstract
Recently, cerebrospinal fluid (CSF) biomarkers related to Alzheimer’s disease (AD) have garnered a lot of clinical attention. To explore neurophysiological traits of AD and parameters for its clinical diagnosis, we examined the association between CSF biomarkers and electroencephalography (EEG) parameters in 14 probable AD patients. Using exact low-resolution electromagnetic tomography (eLORETA), artifact-free 40-sesond EEG data were estimated with current source density (CSD) and lagged phase synchronization (LPS) as the EEG parameters. Correlations between CSF biomarkers and the EEG parameters were assessed. Patients with AD showed significant negative correlation between CSF beta-amyloid (Aβ)-42 concentration and the logarithms of CSD over the right temporal area in the theta band. Total tau concentration was negatively correlated with the LPS between the left frontal eye field and the right auditory area in the alpha-2 band in patients with AD. Our study results suggest that AD biomarkers, in particular CSF Aβ42 and total tau concentrations are associated with the EEG parameters CSD and LPS, respectively. Our results could yield more insights into the complicated pathology of AD.
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- 2016
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24. S14-1 New approach of EEG and brain images in epilepsy
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Banri Tsukuda, Masahiro Hata, Koji Katsura, Shunichiro Ikeda, Masafumi Yoshimura, Shota Minami, Satsuki Ueda, Roberto D. Pascual-Marqui, Masao Iwase, Toshihiko Kinoshita, and Ryouhei Ishii
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Epilepsy ,Neurology ,medicine.diagnostic_test ,business.industry ,Physiology (medical) ,medicine ,Neurology (clinical) ,Electroencephalography ,medicine.disease ,business ,Neuroscience ,Sensory Systems - Published
- 2020
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25. Changes of clinical symptoms in patients with new psychoactive substance (NPS)-related disorders from fiscal year 2012 to 2014: A study in hospitals specializing in the treatment of addiction
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Toshihiko Matsumoto, Tetsuji Cho, Shunichiro Ikeda, Daisuke Funada, Yasunari Kawasoe, Yuko Tanibuchi, Satoru Sakakibara, Takashi Sunami, Takeo Muto, and Nobuya Naruse
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Adult ,Hospitals, Psychiatric ,Male ,medicine.medical_specialty ,Hallucinations ,Substance-Related Disorders ,media_common.quotation_subject ,Psychoactive substance ,Motor Activity ,Delusions ,Syncope ,Fiscal year ,new psychoactive substance ,Japan ,Seizures ,Internal medicine ,medicine ,Psychiatric hospital ,Humans ,Pharmacology (medical) ,In patient ,Coma ,psychiatric hospital ,media_common ,Pharmacology ,Psychotropic Drugs ,Medical treatment ,government regulation ,business.industry ,Addiction ,Medical record ,Original Articles ,Middle Aged ,substance‐related disorders ,Psychiatry and Mental health ,Clinical Psychology ,Female ,Original Article ,addiction ,medicine.symptom ,business - Abstract
Aims The use of new psychoactive substances (NPS) has become increasingly widespread over the last decade, in Japan and internationally. NPS are associated with a range of increasingly serious clinical, public, and social issues. Political measures to ameliorate the effects of NPS in Japan have focused on tightening regulation rather than establishing treatment methods. The current study sought to compare the neuropsychiatric symptoms of patients with NPS‐related disorders across several years. We examined patients who attended specialized hospitals for treating addiction, to elucidate the impacts of legal measures to control NPS. Methods Subjects (n = 864) were patients with NPS‐related disorders who received medical treatment at eight specialized hospitals for treating addiction in Japan between April 2012 and March 2015. Clinical information was collected retrospectively from medical records. Results Among psychiatric symptoms, the ratio of hallucinations/delusions decreased over time across 3 years of study (first year vs second year vs third year: 40.1% vs 30.9% vs 31.7%, P = 0.037). Among neurological symptoms, the ratio of coma/syncope increased over the 3‐year period (7.8% vs 11.0% vs 17.0%, P = 0.002), as did the ratio of convulsions (2.8% vs 4.3% vs 9.7%, P = 0.001). Conclusion The symptoms associated with NPS were primarily psychiatric in the first year, while the prevalence of neurological symptoms increased each year. The risk of death and the severity of symptoms were greater in the third year compared with the first year, as regulation of NPS increased., We collected information retrospectively based on medical records and compared with psychiatric and neurological symptoms of NPS users observed in the fiscal year of their first medical examination. We found that adverse health effects resulting from the use of NPS were changed from mainly psychiatric symptoms to neurological symptoms. These findings suggest the possibility that contained more dangerous and toxic compounds after drug‐related regulations had been tightened.
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- 2018
26. Automated Source Estimation of Scalp EEG Epileptic Activity Using eLORETA Kurtosis Analysis
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Keiichiro Nishida, Koji Katsura, Leonides Canuet, Roberto D. Pascual-Marqui, Shunichiro Ikeda, Ryouhei Ishii, Masafumi Yoshimura, Toshihiko Kinoshita, Y. Kitaura, and University of Zurich
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Male ,Visual interpretation ,Computer science ,Frequency band ,Statistics as Topic ,610 Medicine & health ,Electroencephalography ,Pattern Recognition, Automated ,3206 Neuropsychology and Physiological Psychology ,2738 Psychiatry and Mental Health ,03 medical and health sciences ,Epilepsy ,0302 clinical medicine ,Imaging, Three-Dimensional ,Eeg data ,Seizures ,medicine ,Humans ,Biological Psychiatry ,Aged ,Brain Mapping ,Scalp ,medicine.diagnostic_test ,business.industry ,Brain ,Reproducibility of Results ,Pattern recognition ,Scalp eeg ,medicine.disease ,10074 The KEY Institute for Brain-Mind Research ,030227 psychiatry ,Epileptic activity ,Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Epilepsy, Temporal Lobe ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,Kurtosis ,Female ,Artificial intelligence ,business ,2803 Biological Psychiatry ,030217 neurology & neurosurgery - Abstract
Objectives: eLORETA (exact low-resolution brain electromagnetic tomography) is a technique created by Pascual-Marqui et al. [Int J Psychophysiol. 1994 Oct; 18(1): 49–65] for the 3-dimensional representation of current source density in the brain by electroencephalography (EEG) data. Kurtosis analysis allows for the identification of spiky activity in the brain. In this study, we focused on the evaluation of the reliability of eLORETA kurtosis analysis. For this purpose, the results of eLORETA kurtosis source localization of paroxysmal activity in EEG were compared with those of eLORETA current source density (CSD) analysis of EEG data in 3 epilepsy patients with partial seizures. Methods: EEG was measured using a digital EEG system with 19 channels. We set the bandpass filter at traditional frequency band settings (1–4, 4–8, 8–15, 15–30, and 30–60 Hz) and 5–10 and 20–70 Hz and performed eLORETA kurtosis to compare the source localization of paroxysmal activity with that of visual interpretation of EEG data and CSD analysis of eLORETA in focal epilepsy patients. Results: The eLORETA kurtosis analysis of EEG data preprocessed by bandpass filtering from 20 to 70 Hz and traditional frequency band settings did not show any discrete paroxysmal source activity compatible with the results of CSD analysis of eLORETA. In all 3 cases, eLORETA kurtosis analysis filtered at 5–10 Hz showed paroxysmal activities in the theta band, which were all consistent with the visual inspection results and the CSD analysis results. Discussion: Our findings suggested that eLORETA kurtosis analysis of EEG data might be useful for the identification of spiky paroxysmal activity sources in epilepsy patients. Since EEG is widely used in the clinical practice of epilepsy, eLORETA kurtosis analysis is a promising method that can be applied to epileptic activity mapping.
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- 2018
27. Comparison of conservative treatment versus transcatheter arterial embolisation for the treatment of spontaneously ruptured hepatocellular carcinoma
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Young Ho Choi, Shunichiro Ikeda, Sadao Hayashi, Masashi Shimohira, Yasutaka Baba, Chihaya Koriyama, Takashi Yoshiura, Yuta Shibamoto, and Kohei Shinmura
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Original Paper ,medicine.medical_specialty ,Prognostic factor ,business.industry ,Significant difference ,Portal vein ,hepatocellular carcinoma ,medicine.disease ,Thrombosis ,Gastroenterology ,Conservative treatment ,03 medical and health sciences ,0302 clinical medicine ,transcatheter arterial embolization (TAE) ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Internal medicine ,Medicine ,rupture ,030211 gastroenterology & hepatology ,prognosis ,business ,Survival rate ,Median survival - Abstract
Purpose To elucidate the prognostic factors in the spontaneous rupture of hepatocellular carcinoma (HCC) and to determine whether transcatheter arterial embolisation (TAE) is associated with better prognosis compared to conservative treatment. Material and methods A retrospective multicentre study was conducted involving 71 patients with spontaneous rupture of HCC. A conservative treatment group (Cons T group) included 20 patients, while a transcatheter arterial embolisation group (TAE group) included 51 patients. Results The median survival time (MST) in the Cons T group was only 16 days and the survival rate was 39% at one month, whereas the MST in the TAE group was 28 days and the one month survival rate was 63%. However, there is no statistically significant difference in the overall survival between Cons T and TAE groups (p = 0.213). Multivariable analysis identified only the presence of distant metastasis as an independent prognostic factor (p = 0.023). A subanalysis including patients without distant metastasis showed that the presence of portal vein tumour thrombosis was a significant prognostic factor (p = 0.015). Conclusions Distant metastasis appears to be a prognostic factor in spontaneous rupture of HCC. In cases without distant metastasis, portal vein tumour thrombosis could influence the prognosis. Our data failed to prove any benefit of TAE as the primary management.
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- 2018
28. Association of cerebrospinal fluid tap-related oscillatory activity and shunt outcome in idiopathic normal-pressure hydrocephalus
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Hiroaki Kazui, Shunichiro Ikeda, Toshihisa Tanaka, Masao Iwase, Yasunori Aoki, Ryouhei Ishii, Roberto D. Pascual-Marqui, Masahiro Hata, Masatoshi Takeda, Leonides Canuet, and Kenji Yoshiyama
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Temporal cortex ,medicine.medical_specialty ,Pathology ,medicine.diagnostic_test ,Electroencephalography ,medicine.disease ,Shunt operation ,Hydrocephalus ,Psychiatry and Mental health ,Electrophysiology ,Cerebrospinal fluid ,Internal medicine ,(Idiopathic) normal pressure hydrocephalus ,medicine ,Cardiology ,Geriatrics and Gerontology ,Psychology ,Gerontology ,Shunt (electrical) - Abstract
BACKGROUND: Idiopathic normal-pressure hydrocephalus (iNPH) is a neuropsychiatric syndrome characterized by the clinical triad of gait disturbance, urinary dysfunction, and cognitive impairment. The aim of the present study was to find specific EEG patterns associated with shunt response in iNPH. METHODS: Twenty five iNPH patients (10 shunt responders and 15 non-responders) were enrolled in this study. We performed current source density (CSD) analysis in several frequency bands (delta: 2-4 Hz, theta: 4-8 Hz, alpha: 8-13 Hz, beta: 13-30 Hz, gamma: 30-60 Hz) using exact Low Resolution Brain Electromagnetic Tomography (eLORETA). CSD distribution was compared between shunt responders and non-responders for each frequency band before and after CSF tap test. RESULTS: Shunt responders showed increased gamma CSD in the left temporal cortex before CSF tapping relative to non-responders. However, after CSF tapping, shunt response was associated with significantly higher CSDs in several frequency bands, specifically theta, alpha, beta and gamma, involving mainly the frontal and temporal areas. Using eLORETA analysis, we were able to identify cortical oscillatory activity before and after CSF tap test related to clinical recovery due to shunt operation in iNPH. CONCLUSION: Our findings support and extend the results of previous studies examining the effects of CSF tap test and shunt operation in patients with iNPH, possibly indicating electrophysiological features of shunt response in this disease. These findings warrant future studies to use EEG for prediction of shunt response in iNPH.
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- 2015
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29. Alpha event-related synchronization after eye closing differs in Alzheimer's disease and dementia with Lewy bodies: a magnetoencephalography study
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Yasunori Aoki, Hideki Kanemoto, Manabu Ikeda, Shunsuke Sato, Hiroaki Kazui, Shunichiro Ikeda, Yukiko Suzuki, Ryouhei Ishii, Ryu Kurimoto, Shingo Azuma, Masao Iwase, Kenji Yoshiyama, Masahiro Hata, Leonides Canuet, and Takashi Suehiro
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0301 basic medicine ,Lewy Body Disease ,Male ,medicine.medical_specialty ,Alpha (ethology) ,Audiology ,Electroencephalography ,03 medical and health sciences ,0302 clinical medicine ,Inferior temporal gyrus ,Alzheimer Disease ,Cortex (anatomy) ,mental disorders ,medicine ,Humans ,Cortical Synchronization ,Ocular Physiological Phenomena ,Aged ,Aged, 80 and over ,Cerebral Cortex ,medicine.diagnostic_test ,Blinking ,business.industry ,Dementia with Lewy bodies ,Magnetoencephalography ,Neurophysiology ,medicine.disease ,Psychiatry and Mental health ,Alpha Rhythm ,030104 developmental biology ,medicine.anatomical_structure ,nervous system ,Visual Perception ,Female ,sense organs ,Geriatrics and Gerontology ,Differential diagnosis ,business ,Gerontology ,030217 neurology & neurosurgery - Abstract
Background The electroencephalography (EEG) abnormalities found in patients with dementia with Lewy bodies (DLB) are conflicting. In this study, we used magnetoencephalography, which has higher spatial resolution than electroencephalography, to explore neurophysiological features of DLB that may aid in the differential diagnosis. Methods Six patients with DLB, 11 patients with Alzheimer's disease, and 11 age-matched normal subjects were recruited. We investigated alterations in the ratio of event-related synchronization (ERS) in the alpha band after eye-closing. Results Although the averaged ratio change of alpha ERS after eye-closing appeared predominantly in the posterior brain regions in all study groups, DLB patients had the weakest ratio change of alpha ERS. In particular, DLB patients exhibited a significantly reduced ratio change of alpha ERS in the bilateral inferior temporal gyrus, right occipital pole, and left parieto-occipital cortex compared to Alzheimer's disease patients or normal controls. Conclusion Our findings indicated that a reduced ratio change of alpha ERS in the posterior brain regions elicited by eye-closing is a brain electromagnetic feature of DLB.
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- 2017
30. The cross-frequency mediation mechanism of intracortical information transactions
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Keiichiro Nishida, Kieko Kochi, Pascal L. Faber, Y. Kitaura, Ryouhei Ishii, Shunichiro Ikeda, Patricia Milz, Masafumi Yoshimura, Toshihiko Kinoshita, Roberto D. Pascual-Marqui, and University of Zurich
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Mediation (statistics) ,Computer science ,Mechanism (biology) ,Scale (chemistry) ,Information processing ,610 Medicine & health ,Type (model theory) ,Discrete Fourier transform ,Synchronization ,10074 The KEY Institute for Brain-Mind Research ,Product (mathematics) ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,FOS: Biological sciences ,Quantitative Biology - Neurons and Cognition ,Neurons and Cognition (q-bio.NC) ,Algorithm - Abstract
In a seminal paper by von Stein and Sarnthein (2000), it was hypothesized that "bottom-up" information processing of "content" elicits local, high frequency (beta-gamma) oscillations, whereas "top-down" processing is "contextual", characterized by large scale integration spanning distant cortical regions, and implemented by slower frequency (theta-alpha) oscillations. This corresponds to a mechanism of cortical information transactions, where synchronization of beta-gamma oscillations between distant cortical regions is mediated by widespread theta-alpha oscillations. It is the aim of this paper to express this hypothesis quantitatively, in terms of a model that will allow testing this type of information transaction mechanism. The basic methodology used here corresponds to statistical mediation analysis, originally developed by (Baron and Kenny 1986). We generalize the classical mediator model to the case of multivariate complex-valued data, consisting of the discrete Fourier transform coefficients of signals of electric neuronal activity, at different frequencies, and at different cortical locations. The "mediation effect" is quantified here in a novel way, as the product of "dual frequency RV-coupling coefficients", that were introduced in (Pascual-Marqui et al 2016, http://arxiv.org/abs/1603.05343). Relevant statistical procedures are presented for testing the cross-frequency mediation mechanism in general, and in particular for testing the von Stein & Sarnthein hypothesis., https://doi.org/10.1101/119362 licensed as CC-BY-NC-ND 4.0 International license: http://creativecommons.org/licenses/by-nc-nd/4.0/
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- 2017
31. Functional localization and effective connectivity of cortical theta and alpha oscillatory activity during an attention task
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Masafumi Yoshimura, Hiroshi Mii, Roberto D. Pascual-Marqui, Satsuki Ueda, Y. Kitaura, Ryouhei Ishii, Shunichiro Ikeda, Toshihiko Kinoshita, Keiichiro Nishida, Koji Katsura, University of Zurich, and Nishida, Keiichiro
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sLORETA ,Alpha (ethology) ,610 Medicine & health ,Quantitative EEG ,Electroencephalography ,050105 experimental psychology ,lcsh:RC321-571 ,Task (project management) ,Directional connectivity ,03 medical and health sciences ,2737 Physiology (medical) ,0302 clinical medicine ,Physiology (medical) ,Frontal midline theta ,Attention network ,medicine ,Premovement neuronal activity ,Fronto-parietal network ,Attention task ,0501 psychology and cognitive sciences ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Anterior cingulate cortex ,iCoh ,Resting state fMRI ,medicine.diagnostic_test ,Working memory ,05 social sciences ,Subtraction ,Directional flow ,10074 The KEY Institute for Brain-Mind Research ,2728 Neurology (clinical) ,medicine.anatomical_structure ,Neurology ,Mental arithmetic ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,2808 Neurology ,Clinical and Research Article ,Granger causality ,Neurology (clinical) ,Psychology ,Neuroscience ,030217 neurology & neurosurgery ,Cognitive psychology - Abstract
Highlights • sLORETA analyses performed on 14 healthy adults at rest and during an arithmetic task. • Theta and alpha directed connectivity revealed ACC and left IPL as hubs during task. • Information flow between left IFG and STG suggested a feedback loop., Objectives The aim of this paper is to investigate cortical electric neuronal activity as an indicator of brain function, in a mental arithmetic task that requires sustained attention, as compared to the resting state condition. The two questions of interest are the cortical localization of different oscillatory activities, and the directional effective flow of oscillatory activity between regions of interest, in the task condition compared to resting state. In particular, theta and alpha activity are of interest here, due to their important role in attention processing. Methods We adapted mental arithmetic as an attention ask in this study. Eyes closed 61-channel EEG was recorded in 14 participants during resting and in a mental arithmetic task (“serial sevens subtraction”). Functional localization and connectivity analyses were based on cortical signals of electric neuronal activity estimated with sLORETA (standardized low resolution electromagnetic tomography). Functional localization was based on the comparison of the cortical distributions of the generators of oscillatory activity between task and resting conditions. Assessment of effective connectivity was based on the iCoh (isolated effective coherence) method, which provides an appropriate frequency decomposition of the directional flow of oscillatory activity between brain regions. Nine regions of interest comprising nodes from the dorsal and ventral attention networks were selected for the connectivity analysis. Results Cortical spectral density distribution comparing task minus rest showed significant activity increase in medial prefrontal areas and decreased activity in left parietal lobe for the theta band, and decreased activity in parietal-occipital regions for the alpha1 band. At a global level, connections among right hemispheric nodes were predominantly decreased during the task condition, while connections among left hemispheric nodes were predominantly increased. At more detailed level, decreased flow from right inferior frontal gyrus to anterior cingulate cortex for theta, and low and high alpha oscillations, and increased feedback (bidirectional flow) between left superior temporal gyrus and left inferior frontal gyrus, were observed during the arithmetic task. Conclusions Task related medial prefrontal increase in theta oscillations possibly corresponds to frontal midline theta, while parietal decreased alpha1 activity indicates the active role of this region in the numerical task. Task related decrease of intracortical right hemispheric connectivity support the notion that these nodes need to disengage from one another in order to not interfere with the ongoing numerical processing. The bidirectional feedback between left frontal-temporal-parietal regions in the arithmetic task is very likely to be related to attention network working memory function. Significance The methods of analysis and the results presented here will hopefully contribute to clarify the roles of the different EEG oscillations during sustained attention, both in terms of their functional localization and in terms of how they integrate brain function by supporting information flow between different cortical regions. The methodology presented here might be clinically relevant in evaluating abnormal attention function.
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- 2017
32. Special symposium: The upcoming 90th anniversary in 2019 of Berger’s discovery of EEG-4. New developments in quantitative EEG analysis
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Y. Kitaura, Shunichiro Ikeda, Keiichiro Nishida, Masafumi Yoshimura, Roberto D. Pascual-Marqui, and Toshihiko Kinoshita
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Cognitive science ,Neurology ,medicine.diagnostic_test ,Physiology (medical) ,medicine ,Neurology (clinical) ,Electroencephalography ,Psychology ,Sensory Systems ,Quantitative eeg - Published
- 2019
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33. S2-1. The application of clinical neurophysiology to the dementing diseases
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Takashi Suehiro, Shunichiro Ikeda, Kenji Yoshiyama, Yukiko Suzuki, Hideki Kanemoto, Masahiro Hata, Shunsuke Sato, Hiroaki Kazui, Yasunori Aoki, Toshihisa Tanaka, Ryouhei Ishii, Shingo Azuma, Masao Iwase, and Manabu Ikeda
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medicine.medical_specialty ,Neurology ,business.industry ,Physiology (medical) ,Medicine ,Neurology (clinical) ,business ,Clinical neurophysiology ,Neuroscience ,Sensory Systems - Published
- 2019
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34. S2-3. Utility of microstate analysis in psychiatric disorders
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Masahiro Hata, Masafumi Yoshimura, Yasunori Aoki, Shota Minami, Toshihiko Kinoshita, Ryouhei Ishii, Roberto D. Pascual-Marqui, Y. Kitaura, Koji Katsura, Keiichiro Nishida, and Shunichiro Ikeda
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medicine.medical_specialty ,Neurology ,Ministate ,Physiology (medical) ,medicine ,Neurology (clinical) ,Psychology ,Psychiatry ,Sensory Systems - Published
- 2019
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35. Effective factors of repetitive transcranial magnetic stimulation in major depression: Meta-(Regression) Analysis
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Keiichiro Nishida, Koji Katsura, Masafumi Yoshimura, Shota Minami, Yosuke Morishima, Shunichiro Ikeda, and Toshihiko Kinoshita
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medicine.medical_specialty ,business.industry ,General Neuroscience ,medicine.medical_treatment ,Biophysics ,lcsh:RC321-571 ,Transcranial magnetic stimulation ,Physical medicine and rehabilitation ,medicine ,Meta-regression ,Neurology (clinical) ,business ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Depression (differential diagnoses) - Published
- 2019
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36. Evaluation of Split Renal Function Before and After Renal Arterial Embolization for Angiomyolipoma Using Absolute Ethanol
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Shunichiro Ikeda, Megumi Jinguji, Masatoyo Nakajo, Yasutaka Baba, Sadao Hayashi, and Masayuki Nakajo
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Adult ,Male ,medicine.medical_specialty ,Angiomyolipoma ,medicine.medical_treatment ,Treatment outcome ,Renal function ,Kidney ,Kidney Function Tests ,urologic and male genital diseases ,Technetium Tc 99m Mertiatide ,hemic and lymphatic diseases ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Radionuclide imaging ,Embolization ,Radionuclide Imaging ,neoplasms ,Aged ,Retrospective Studies ,Ethanol ,business.industry ,Arterial Embolization ,Middle Aged ,medicine.disease ,Embolization, Therapeutic ,Kidney Neoplasms ,Treatment Outcome ,medicine.anatomical_structure ,Solvents ,Female ,Radiology ,Radiopharmaceuticals ,Cardiology and Cardiovascular Medicine ,business ,Renal angiomyolipoma - Abstract
Transcatheter arterial embolization (TAE) with absolute ethanol is widely accepted as a therapeutic procedure for renal angiomyolipoma (AML). We aim to evaluate the split renal function before and after AE for renal AML by using 99m-technetium (99mTc)-mercaptoacetyltriglycine 3 (MAG3) renography.This study was approved by the Institutional Review Board. The study population comprised 11 renal AML patients (three males, eight females, age 55.1 ± 13.8 years, AML in eight right and three left kidneys) who received unilateral renal TAE with absolute ethanol from April 2002 to January 2013. Blood renal function (i.e. serum creatinine and estimated glomerular filtration rate [eGFR] and split effective renal plasma flow [ERPF]) calculated on 99mTc-MAG3 renography was compared before and within 1 week after renal AE. Statistical analysis was calculated using Wilcoxon signed-ranked test.TAE for renal AML was technically successful in all patients. Serum creatinine and eGFR did not change before and after TAE. ERPF on the embolized kidney did not change before (127.3 ± 60.8 ml/min) and after (127.6 ± 47.4 ml/min) TAE (p = 0.9726). ERPF on the nonembolized kidney showed a statistically significant increase before (152.5 ± 46.8 ml/min) and within 1 week after (169.1 ± 41.5 ml/min) TAE (p = 0.0093 and p0.05, respectively).TAE for renal AML may not induce renal dysfunction on the embolized kidney and may immediately increase the renal blood flow of the nonembolized kidney.
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- 2013
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37. Comparison of the clinical features of suicide attempters by jumping from a height and those by self-stabbing in Japan
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Shunichiro Ikeda, Makoto Yanagida, Hidenori Matsunaga, Hirokazu Kumazaki, and Ryo Kimura
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Adult ,Male ,medicine.medical_specialty ,Poison control ,Suicide, Attempted ,medicine.disease_cause ,Suicide prevention ,Jumping ,Sex Factors ,Japan ,Injury prevention ,Humans ,Medicine ,Psychiatry ,Suicide attempt ,business.industry ,Mental Disorders ,Age Factors ,Middle Aged ,medicine.disease ,Psychiatry and Mental health ,Clinical Psychology ,Suicide methods ,Mood disorders ,Self-stabbing ,Population study ,Female ,business ,Self-Injurious Behavior ,Suicide attempts - Abstract
Background A history of psychiatric disorders is a high risk for suicide. The present study compared the clinical features of psychiatric patients in Japan who attempted suicide by jumping from a height and those who attempted suicide by self-stabbing. Methods We compared two groups of suicide attempters who were hospitalized for both physical and psychiatric treatment (n=202). We compared the psychiatric diagnoses and clinical features between those who attempted suicide by jumping from a height (N=147) and those who did so by self-stabbing (N=55). Results The self-stabbing group (mean age 52.3 years) was significantly older compared to the jumping group (mean age 37.9 years). A significantly higher proportion of females were found in the jumping group. Jumping from a height was significantly associated with schizophrenia spectrum disorders, whereas self-stabbing was significantly associated with mood disorders. Limitations The results were drawn from data from a single hospital in a large urban city, and the study population did not include subjects who completed their suicide attempts. Conclusions Our findings show that differences in suicide methods (here, between jumping from a height and self-stabbing) may be related to suicide attempters' psychiatric diagnosis, gender and age. It is thus important to obtain a more detailed background information about a patient's suicide attempt and to create suicide prevention plans in accord with individuals' psychiatric diagnosis, age and gender, especially among those who have attempted suicide by jumping from a height or self-stabbing.
- Published
- 2013
38. Efficacy of Uterine Artery Embolization for Patients with Postpartum Hemorrhage
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Sadao Hayashi, Young Ho Choi, Shunichiro Ikeda, Masayuki Nakajo, Young So, and Yasutaka Baba
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Gynecology ,Related factors ,medicine.medical_specialty ,Hysterectomy ,business.industry ,Obstetrics ,Vaginal delivery ,medicine.medical_treatment ,Arterial Embolization ,Uterine artery embolization ,medicine ,Caesarean section ,In patient ,Embolization ,business - Abstract
Purpose: To investigate the efficacy of uterine arterial embolization (UAE) in patients with post-partum hemorrhage (PPH). Materials and Methods: The subjects were 40 women (mean age, 33 years; age range, 21 - 42 years) who underwent UAE for PPH at two institutes from June 2001 to May 2011. The rates of clinical success (avoidance of hysterectomy) and complications were calculated. Differences in related factors between primary PPH and secondary PPH and between caesarean section and vaginal delivery were examined. The risk factors associated with hysterectomy were also examined. Results: The overall clinical success rate was 90% (93% of primary PPH, 77% of secondary PPH, and 87.5% of PPH with cesarean section), and the overall complication rate was 10%. There were significant differences in time to PPH (P = 0.0158) between subtypes of primary and secondary PPH and in blood infusion before UAE (P = 0.0052) between delivery methods. The significant factors associated with hysterectomy were cesarean section (P = 0.02), severe PPH (>1000 mL bleeding, P = 0.03), and embolization of non-uterine arteries (P = 0.02).
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- 2013
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39. Functional connectivity assessed by resting state EEG correlates with cognitive decline of Alzheimer's disease - An eLORETA study
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Toshihisa Tanaka, Shunichiro Ikeda, Hideki Kanemoto, Masahiro Hata, Masatoshi Takeda, Masao Iwase, Ryouhei Ishii, Leonides Canuet, Kenji Yoshiyama, Yasunori Aoki, Roberto D. Pascual-Marqui, Hiroaki Kazui, University of Zurich, and Ishii, Ryouhei
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Male ,Electroencephalography ,Functional connectivity ,0302 clinical medicine ,2737 Physiology (medical) ,EEG ,Cognitive decline ,Lagged phase synchronization ,Aged, 80 and over ,medicine.diagnostic_test ,MMSE (Mini-Mental State Examination) ,05 social sciences ,Brain ,Cognition ,LORETA ,Sensory Systems ,medicine.anatomical_structure ,2728 Neurology (clinical) ,Neurology ,Female ,Alzheimer's disease ,Psychology ,Alzheimer’s disease ,Rest ,Clinical Neurology ,610 Medicine & health ,050105 experimental psychology ,03 medical and health sciences ,2809 Sensory Systems ,Alzheimer Disease ,Physiology (medical) ,medicine ,Dementia ,Humans ,0501 psychology and cognitive sciences ,Anterior cingulate cortex ,Aged ,Neurophysiology ,Phase synchronization ,medicine.disease ,CDR (Clinical Dementia Rating) ,10074 The KEY Institute for Brain-Mind Research ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,2808 Neurology ,Neurology (clinical) ,Nerve Net ,Cognition Disorders ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Objective To explore neurophysiological biomarkers of Alzheimer's disease (AD), we investigated electroencephalography (EEG) of AD patients, and assessed lagged phase synchronization, a measure of brain functional connectivity. Methods Twenty-eight probable AD patients and 30 healthy controls (HC) were enrolled. Forty seconds of artifact-free EEG data were selected and compared between patients with AD and HC. Current source density (CSD) and lagged phase synchronization were analyzed by using eLORETA. Results Patients with AD showed significantly decreased lagged phase synchronization between most cortical regions in delta band relative to controls. There also was a decrease in lagged phase synchronization between the right dorsolateral prefrontal cortex (DLPFC) and the right posterior-inferior parietal lobule (pIPL) in theta band. In addition, some connections in delta band were found to be associated with cognitive function, measured by MMSE. This involved specifically interhemispheric temporal connections as well as left inferior parietal connectivity with the left hippocampus, lateral frontal regions, and the anterior cingulate cortex (aCC). Right temporal connections in delta band were related to global function, as estimated by CDR. No differences were found in CSD analysis between patients and HC. Conclusions Functional connectivity disruptions between certain brain regions, as measured with lagged phase synchronization, may potentially represent a neurophysiological biomarker of AD. Significance Our study indicated that AD and healthy elderly could have the different patterns of lagged phase synchronization.
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- 2016
40. Induced oscillatory responses during the Sternberg's visual memory task in patients with Alzheimer's disease and mild cognitive impairment
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Tetsuhiko Yoshida, Yasunori Aoki, Masatoshi Takeda, Hiroaki Kazui, Leonides Canuet, Hidetoshi Takahashi, Takayuki Nakahachi, Ryouhei Ishii, Masao Iwase, Shunichiro Ikeda, Ryu Kurimoto, Koji Ikezawa, and Michiyo Azechi
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Cerebral Cortex ,Male ,medicine.diagnostic_test ,Working memory ,Cognitive Neuroscience ,Magnetoencephalography ,Posterior parietal cortex ,medicine.disease ,Memory, Short-Term ,medicine.anatomical_structure ,Neurology ,Visual memory ,Alzheimer Disease ,Cortex (anatomy) ,medicine ,Humans ,Female ,Mild cognitive impairment (MCI) ,Cognitive decline ,Cognition Disorders ,Beta (finance) ,Psychology ,Neuroscience ,Aged - Abstract
In this study we used magnetoencephalography during a modified version of the Sternberg's memory recognition task performed by patients with early Alzheimer's disease (AD), mild cognitive impairment (MCI), and by age-matched healthy controls to identify differences in induced oscillatory responses. For analyses, we focused on the retention period of the working memory task. Multiple-source beamformer and Brain Voyager were used for localization of source-power changes across the cortex and for statistic group analyses, respectively. We found significant differences in oscillatory response during the task, specifically in beta and gamma frequency bands: patients with AD showed reduced beta event-related desynchronization (ERD) in the right central area compared to controls, and reduced gamma ERD in the left prefrontal and medial parietal cortex compared to patients with MCI. Our findings suggest that reduced oscillatory responses over certain brain regions in high frequency bands (i.e., beta, gamma), and especially in the beta band that was significantly different between AD patients and healthy subjects, may represent brain electromagnetic changes underlying visual-object working memory dysfunction in early AD, and a neurophysiological indicator of cognitive decline.
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- 2012
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41. Visualization of utero-ovarian anastomoses: Comparison between patients with and without uterine fibroid
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Sadao Hayashi, Tsutomu Douchi, Shunichiro Ikeda, Yasutaka Baba, Masayuki Nakajo, and Mitsushiro Yoshinaga
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Uterine fibroids ,medicine.medical_treatment ,Uterus ,Anastomosis ,medicine.disease ,Surgery ,Exact test ,Leiomyoma ,medicine.anatomical_structure ,Uterine artery embolization ,In utero ,Angiography ,medicine ,Radiology ,business - Abstract
Purpose: To retrospectively review uteroovarian anastomosis (UOA) visualization during uterine artery embolization (UAE) in patients with or without uterine fibroids (UFs). Material and Methods: 43 patients underwent UAE for uterine fibroids (n = 23) and gynecological hemorrhage (n = 20). The frequency of angiographic visualization of UOAs was compared between the two groups and analyzed by the Fisher’s exact test. Results: Except for one patient with no right uterine artery, 85 uterine arteries were evaluated. Of these 85 uterine arteries, 23 UOA were recognized: 14 UOAs (58%) (right: 5 [21.7%], left: 9 [37.5%]) were visualized in 23 patients with UFs, and 9 UOAs (47.4%) (right: 4 [21%], left: 5 [26.3%]) were visualized in 20 patients with gynecological hemorrhage. In both groups, UOA was observed after UAE in one patient. Statistically significant difference was not observed for UOAs visualized between patients with or without UFs except a group of left UAE in patients with UFs (P = 0.036). Conclusion: The frequency of UOAs visualized during angiography was similar between patients with or without UFs. Therefore, UOA should be visualized carefully during UAE in patients with gynecological hemorrhage.
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- 2012
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42. P2-3-8. Change of cross frequency coupling by symptom provocation in Obsessive Compulsive Disorder (OCD) based on sLORETA
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Satsuki Ueda, Roberto D. Pascual-Marqui, Yukiko Saito, Hiroshi Mii, Koji Katsura, Keiichiro Nishida, Masafumi Yoshimura, Toshihiko Kinoshita, Shunichiro Ikeda, Shota Minami, Toshiaki Isotani, and Y. Kitaura
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medicine.medical_specialty ,Cross frequency coupling ,medicine.diagnostic_test ,business.industry ,Precuneus ,Alpha (ethology) ,Symptom provocation ,Electroencephalography ,Audiology ,medicine.disease ,behavioral disciplines and activities ,Sensory Systems ,medicine.anatomical_structure ,Neurology ,Physiology (medical) ,mental disorders ,Medicine ,Premovement neuronal activity ,In patient ,Neurology (clinical) ,business ,Obsessive-compulsive disorder (OCD) - Abstract
We investigated the changes in directional cross frequency interactions between theta and alpha oscillations, across six cortical regions, induced by a symptom provocation procedure, in patients with OCD, and in normal controls. Nine OCD outpatients and nine controls participated in this study. Eyes closed EEG was recorded before and under the instruction to imagine that the towel placed on their hands is contaminated (symptom provocation, SP). Cortical electric neuronal activity were calculated with sLORETA at medial-prefrontal, precuneus, inferior-parietal, and dorsolateral-prefrontal cortices. Instantaneous amplitudes for the theta and alpha bands were obtained and used for computing Granger causal directional cross-frequency, cross-cortical interactions. In controls, SP is characterized by a significant increase in mPFC theta due to right fronto-parietal alpha. In contrast, SP in the OCD group mainly displayed alpha-alpha RIPL alpha decrease due to RDLPFC. A direct comparison of OCD and normal controls showed significant frontal decreases of theta-alpha interactions before SP. The symptom provocation procedure induced functional changes of cross-frequency connections in both groups involving core right hemisphere network nodes. Functional cross-frequency interactions involving all frontal nodes were decreased in OCD compared to controls during SP. These results support the use of cross-frequency interactions a possible trait marker of OCD.
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- 2018
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43. Detection of EEG-resting state independent networks by eLORETA-ICA method
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Masao Iwase, Masahiro Hata, Masatoshi Takeda, Leonides Canuet, Shunichiro Ikeda, Takashi Asada, Roberto D. Pascual-Marqui, Yasunori Aoki, Kaoru Imajo, Haruyasu Matsuzaki, Ryouhei Ishii, Toshimitsu Musha, University of Zurich, and Ishii, Ryouhei
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Medicina ,Frequency band ,Temporoparietal junction ,Precuneus ,resting state network ,610 Medicine & health ,Electroencephalography ,3206 Neuropsychology and Physiological Psychology ,2738 Psychiatry and Mental Health ,Behavioral Neuroscience ,Nuclear magnetic resonance ,2802 Behavioral Neuroscience ,medicine ,Original Research Article ,ICA ,EEG ,Default mode network ,Biological Psychiatry ,Informática ,medicine.diagnostic_test ,Resting state fMRI ,Magnetoencephalography ,LORETA ,10074 The KEY Institute for Brain-Mind Research ,Psychiatry and Mental health ,medicine.anatomical_structure ,Neuropsychology and Physiological Psychology ,eLORETA-ICA ,Neurology ,independent component analysis ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,2808 Neurology ,Electrónica ,Functional magnetic resonance imaging ,Psychology ,2803 Biological Psychiatry ,Neuroscience - Abstract
Recent functional magnetic resonance imaging (fMRI) studies have shown that functional networks can be extracted even from resting state data, the so called ?Resting State independent Networks? (RS-independent-Ns) by applying independent component analysis (ICA). However, compared to fMRI, electroencephalography (EEG) and magnetoencephalography (MEG) have much higher temporal resolution and provide a direct estimation of cortical activity. To date, MEG studies have applied ICA for separate frequency bands only, disregarding cross-frequency couplings. In this study, we aimed to detect EEG-RS-independent-Ns and their interactions in all frequency bands. We applied exact low resolution brain electromagnetic tomography-ICA (eLORETA-ICA) to resting-state EEG data in 80 healthy subjects using five frequency bands (delta, theta, alpha, beta and gamma band) and found five RS-independent-Ns in alpha, beta and gamma frequency bands. Next, taking into account previous neuroimaging findings, five RS-independent-Ns were identified: (1) the visual network in alpha frequency band, (2) dual-process of visual perception network, characterized by a negative correlation between the right ventral visual pathway (VVP) in alpha and beta frequency bands and left posterior dorsal visual pathway (DVP) in alpha frequency band, (3) self-referential processing network, characterized by a negative correlation between the medial prefrontal cortex (mPFC) in beta frequency band and right temporoparietal junction (TPJ) in alpha frequency band, (4) dual-process of memory perception network, functionally related to a negative correlation between the left VVP and the precuneus in alpha frequency band; and (5) sensorimotor network in beta and gamma frequency bands. We selected eLORETA-ICA which has many advantages over the other network visualization methods and overall findings indicate that eLORETA-ICA with EEG data can identify five RS-independent-Ns in their intrinsic frequency bands, and correct correlations within RS-independent-Ns.
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- 2015
44. Noninvasive prediction of shunt operation outcome in idiopathic normal pressure hydrocephalus
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Themistoklis Katsimichas, Kenji Yoshiyama, Masahiro Hata, Masatoshi Takeda, Leonides Canuet, Kaoru Imajo, Haruyasu Matsuzaki, Tetsuhiko Yoshida, Yasunori Aoki, Hiroaki Kazui, Ryouhei Ishii, Hideki Kanemoto, Shunichiro Ikeda, Toshihisa Tanaka, Keiko Nomura, Toshimitsu Musha, Masao Iwase, and Tamiki Wada
- Subjects
Male ,medicine.medical_specialty ,Medicina ,Urinary incontinence ,Electroencephalography ,Article ,Shunt operation ,03 medical and health sciences ,0302 clinical medicine ,Cognition ,Internal medicine ,medicine ,Humans ,Beta Rhythm ,Electrodes ,Gait ,030304 developmental biology ,Aged ,Demography ,Informática ,0303 health sciences ,Multidisciplinary ,medicine.diagnostic_test ,business.industry ,Gait Disturbance ,Discriminant Analysis ,medicine.disease ,Cerebrospinal Fluid Shunts ,Hydrocephalus, Normal Pressure ,Surgery ,Hydrocephalus ,Treatment Outcome ,Cardiology ,Electrónica ,Female ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Shunt (electrical) - Abstract
Idiopathic normal pressure hydrocephalus (iNPH) is a syndrome characterized by gait disturbance, cognitive deterioration and urinary incontinence in elderly individuals. These symptoms can be improved by shunt operation in some but not all patients. Therefore, discovering predictive factors for the surgical outcome is of great clinical importance. We used normalized power variance (NPV) of electroencephalography (EEG) waves, a sensitive measure of the instability of cortical electrical activity, and found significantly higher NPV in beta frequency band at the right fronto-temporo-occipital electrodes (Fp2, T4 and O2) in shunt responders compared to non-responders. By utilizing these differences, we were able to correctly identify responders and non-responders to shunt operation with a positive predictive value of 80% and a negative predictive value of 88%. Our findings indicate that NPV can be useful in noninvasively predicting the clinical outcome of shunt operation in patients with iNPH.
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- 2015
45. Emotion Regulation of Neuroticism: Emotional Information Processing Related to Psychosomatic State Evaluated by Electroencephalography and Exact Low-Resolution Brain Electromagnetic Tomography
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Themistoklis Katsimichas, Yuko Mizuno-Matsumoto, Masahiro Hata, Masatoshi Takeda, Eika Okamoto, Takuto Hayashi, Yasunori Aoki, Leonides Canuet, Masao Iwase, Ryouhei Ishii, Shunichiro Ikeda, Tetsuya Asakawa, Roberto D. Pascual-Marqui, and University of Zurich
- Subjects
medicine.medical_specialty ,Brain activity and meditation ,Medicina ,media_common.quotation_subject ,610 Medicine & health ,Electroencephalography ,Audiology ,Amygdala ,050105 experimental psychology ,Developmental psychology ,3206 Neuropsychology and Physiological Psychology ,03 medical and health sciences ,2738 Psychiatry and Mental Health ,0302 clinical medicine ,Inferior temporal gyrus ,medicine ,Personality ,0501 psychology and cognitive sciences ,Biological Psychiatry ,media_common ,Informática ,medicine.diagnostic_test ,05 social sciences ,Neurophysiology ,Neuroticism ,Psicología ,10074 The KEY Institute for Brain-Mind Research ,Psychiatry and Mental health ,Electrophysiology ,Neuropsychology and Physiological Psychology ,medicine.anatomical_structure ,10054 Clinic for Psychiatry, Psychotherapy, and Psychosomatics ,Electrónica ,Psychology ,2803 Biological Psychiatry ,030217 neurology & neurosurgery - Abstract
Emotion regulation is the process that adjusts the type or amount of emotion when we experience an emotional situation. The aim of this study was to reveal quantitative changes in brain activity during emotional information processing related to psychosomatic states and to determine electrophysiological features of neuroticism. Twenty-two healthy subjects (mean age 25 years, 14 males and 8 females) were registered. Electroencephalography (EEG) was measured during an emotional audiovisual memory task under three conditions (neutral, pleasant and unpleasant sessions). We divided the subjects into two groups using the Cornell Medical Index (CMI): (CMI-I: control group, n = 10: CMI-II, III or IV: neuroticism group, n = 12). We analyzed the digital EEG data using exact low-resolution brain electromagnetic tomography (eLORETA) current source density (CSD) and functional connectivity analysis in several frequency bands (δ, θ, α, β, γ and whole band). In all subjects, bilateral frontal α CSD in the unpleasant session increased compared to the pleasant session, especially in the control group (p < 0.05). CSD of the neuroticism group was significantly higher than that of the control group in the full band at the amygdala and inferior temporal gyrus, and in the α band at the right temporal lobe (p < 0.05). Additionally, we found an increase in functional connectivity between the left insular cortex and right superior temporal gyrus in all subjects during the unpleasant session compared to the pleasant session (p < 0.05). In this study, using EEG analysis, we could find a novel cortical network related to brain mechanisms underlying emotion regulation. Overall findings indicate that it is possible to characterize neuroticism electrophysiologically, which may serve as a neurophysiological marker of this personality trait.
- Published
- 2015
46. Source estimation of epileptic activity using eLORETA kurtosis analysis
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Shunichiro Ikeda, Ryouhei Ishii, Leonides Canuet, and Roberto D. Pascual-Marqui
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Adult ,Male ,medicine.medical_specialty ,genetic structures ,clinical neurophysiology ,Electroencephalography ,Clinical neurophysiology ,050105 experimental psychology ,epilepsy and seizures ,03 medical and health sciences ,Epilepsy ,0302 clinical medicine ,Novel Diagnostic Procedure ,Seizures ,Humans ,Medicine ,0501 psychology and cognitive sciences ,In patient ,Psychiatry ,medicine.diagnostic_test ,business.industry ,05 social sciences ,Magnetoencephalography ,Reproducibility of Results ,Pattern recognition ,General Medicine ,medicine.disease ,psychiatry ,Epileptic activity ,Kurtosis ,Artificial intelligence ,Synthetic-aperture magnetometry ,business ,030217 neurology & neurosurgery - Abstract
Exact low-resolution brain electromagnetic tomography (eLORETA) is a technique for three-dimensional representation of the distribution of sources of electrical activity in the brain. Kurtosis analysis allows for identification of spiky activity in the brain. To evaluate the reliability of eLORETA kurtosis analysis, the results of the analysis were compared with those of equivalent current dipole (ECD) and synthetic aperture magnetometry (SAM) kurtosis analysis of magnetoencephalography (MEG) data in a patient with epilepsy with elementary visual seizures in a 6-year follow-up. The results of electroencephalography (EEG) eLORETA kurtosis analysis indicative of a right superior temporal spike source partially overlapped with MEG ECD/SAM kurtosis results in all recordings, with a total overlapping at the end of the follow-up period. Overall findings suggest that eLORETA kurtosis analysis of EEG data may aid in the localisation of spike activity sources in patients with epilepsy.
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- 2017
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47. O3-7-17. Detection of Resting state network activity using eLORETA-ICA in Dementia with Lewy Bodies
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Shunsuke Sato, Hiroaki Kazui, Yasunori Aoki, Shunichiro Ikeda, Masahiro Hata, Ryouhei Ishii, Yukiko Suzuki, Hideki Kanemoto, Roberto D. Pascual-Marqui, Kenji Yoshiyama, and Masao Iwase
- Subjects
Visual perception ,genetic structures ,Resting state fMRI ,Working memory ,Dementia with Lewy bodies ,Parkinsonism ,Cognition ,medicine.disease ,Sensory Systems ,Neurology ,Physiology (medical) ,medicine ,Dementia ,Semantic memory ,Neurology (clinical) ,Psychology ,Neuroscience - Abstract
Dementia with Lewy bodies (DLB) is the second most common type of dementia and characterized by progressive cognitive decline, fluctuating cognition, visual hallucinations and Parkinsonism. However, pathophysiological mechanism of these symptoms remain poorly understood. In this study, using exact low resolution brain electromagnetic tomography-independent component analysis (eLORETA-ICA), we assessed activities of five electroencephalography-resting state networks (EEG-RSNs) in 49 DLB patients who were not administered acetylcholinesterase inhibitors. The results were that DLB patients had significantly decreased activities in the occipital visual network and memory perception network, and significantly enhanced activities in the visual perception network and self-referential network compared to 80 healthy controls. Furthermore, we found correlations between these network activities and DLB symptoms. In particular, enhanced visual perception network activity correlated with severe delusions. Enhanced self-referential network activity correlated with worse working memory. Decreased memory perception network activity correlated with worse semantic memory. In addition, sensorimotor network activity correlated with milder delusions, aberrant motor behavior and fluctuating cognition as well as with more severe Parkinsonism. These results indicate that eLORETA-ICA can sensitively detect EEG-RSN activity changes in DLB related to symptoms. Therefore, eLORETA-ICA with EEG data will be a powerful tool for understanding of neurophysiological mechanisms underlying this disease.
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- 2017
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48. The neurophysiological connectivity changing in patients with depression is depends on the anodal stimulation area
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Masafumi Yoshimura, R. Ishi, Koji Katsura, Shunichiro Ikeda, Roberto D. Pascual-Marqui, Keiichiro Nishida, Toshihiko Kinoshita, Ai Onohara, Yosuke Koshikawa, and Satsuki Ueda
- Subjects
business.industry ,General Neuroscience ,Biophysics ,Medicine ,In patient ,Neurology (clinical) ,Neurophysiology ,Anodal stimulation ,business ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Neuroscience ,Depression (differential diagnoses) ,lcsh:RC321-571 - Published
- 2017
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49. Association of cerebrospinal fluid tap-related oscillatory activity and shunt outcome in idiopathic normal-pressure hydrocephalus
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Shunichiro, Ikeda, Hiroaki, Kazui, Toshihisa, Tanaka, Ryouhei, Ishii, Yasunori, Aoki, Masahiro, Hata, Leonides, Canuet, Kenji, Yoshiyama, Masao, Iwase, Roberto, Pascual-Marqui, and Masatoshi, Takeda
- Subjects
Aged, 80 and over ,Male ,Brain ,Electroencephalography ,Neuroimaging ,Middle Aged ,Spinal Puncture ,Cerebrospinal Fluid Shunts ,Hydrocephalus, Normal Pressure ,Urinary Incontinence ,Humans ,Female ,Cognition Disorders ,Gait Disorders, Neurologic ,Aged - Abstract
Idiopathic normal-pressure hydrocephalus (iNPH) is a neuropsychiatric syndrome characterized by the clinical triad of gait disturbance, urinary dysfunction, and cognitive impairment. The aim of the present study was to find specific EEG patterns associated with shunt response in iNPH.Twenty five iNPH patients (10 shunt responders and 15 non-responders) were enrolled in this study. We performed current source density (CSD) analysis in several frequency bands (delta: 2-4 Hz, theta: 4-8 Hz, alpha: 8-13 Hz, beta: 13-30 Hz, gamma: 30-60 Hz) using exact Low Resolution Brain Electromagnetic Tomography (eLORETA). CSD distribution was compared between shunt responders and non-responders for each frequency band before and after CSF tap test.Shunt responders showed increased gamma CSD in the left temporal cortex before CSF tapping relative to non-responders. However, after CSF tapping, shunt response was associated with significantly higher CSDs in several frequency bands, specifically theta, alpha, beta and gamma, involving mainly the frontal and temporal areas. Using eLORETA analysis, we were able to identify cortical oscillatory activity before and after CSF tap test related to clinical recovery due to shunt operation in iNPH.Our findings support and extend the results of previous studies examining the effects of CSF tap test and shunt operation in patients with iNPH, possibly indicating electrophysiological features of shunt response in this disease. These findings warrant future studies to use EEG for prediction of shunt response in iNPH.
- Published
- 2014
50. Frontal midline theta rhythm and gamma power changes during focused attention on mental calculation: an MEG beamformer analysis
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Shunichiro Ikeda, Masao Iwase, Hidetoshi Takahashi, Yasunori Aoki, Atsuko Gunji, Takayuki Nakahachi, Tsutomu Ishihara, Ryouhei Ishii, Masahiro Hata, Masatoshi Takeda, Leonides Canuet, and Themistoklis Katsimichas
- Subjects
Theta rhythm ,gamma band ,spatial filtering ,frontal midline theta ,Electroencephalography ,lcsh:RC321-571 ,Behavioral Neuroscience ,Neural activity ,magnetoencephalography(MEG) ,spatialfiltering ,Event-related desynchronization (ERD) ,medicine ,magnetoencephalography (MEG) ,Original Research Article ,Prefrontal cortex ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Biological Psychiatry ,Gamma power ,medicine.diagnostic_test ,Subtraction ,Cognition ,synthetic aperture magnetometry (SAM) ,Mental calculation ,Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Neurology ,beamformer ,arithmetic calculation ,syntheticaperturemagnetometry(SAM) ,Psychology ,Neuroscience ,focused attention - Abstract
Frontal midline theta rhythm (Fmθ) appears widely distributed over medial prefrontal areas in EEG recordings, indicating focused attention. Although mental calculation is often used as an attention-demanding task, little has been reported on calculation-related activation in Fmθ experiments. In this study we used spatially filtered MEG and permutation analysis to precisely localize cortical generators of the magnetic counterpart of Fmθ, as well as other sources of oscillatory activity associated with mental calculation processing (i.e., arithmetic subtraction). Our results confirmed and extended earlier EEG/MEG studies indicating that Fmθ during mental calculation is generated in the dorsal anterior cingulate and adjacent medial prefrontal cortex. Mental subtraction was also associated with gamma event-related synchronization, as an index of activation, in right parietal regions subserving basic numerical processing and number-based spatial attention. Gamma event-related desynchronization appeared in the right lateral prefrontal cortex, likely representing a mechanism to interrupt neural activity that can interfere with the ongoing cognitive task.
- Published
- 2014
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