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Shibata T, Hattori N, Nishijo H, Kuroda S, Takakusaki K. Evolutionary origin of alpha rhythms in vertebrates. Front Behav Neurosci 2024; 18:1384340. [PMID: 38651071 PMCID: PMC11033391 DOI: 10.3389/fnbeh.2024.1384340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 03/25/2024] [Indexed: 04/25/2024] Open
Abstract
The purpose of this review extends beyond the traditional triune brain model, aiming to elucidate the evolutionary aspects of alpha rhythms in vertebrates. The forebrain, comprising the telencephalon (pallium) and diencephalon (thalamus, hypothalamus), is a common feature in the brains of all vertebrates. In mammals, evolution has prioritized the development of the forebrain, especially the neocortex, over the midbrain (mesencephalon) optic tectum, which serves as the prototype for the visual brain. This evolution enables mammals to process visual information in the retina-thalamus (lateral geniculate nucleus)-occipital cortex pathway. The origin of posterior-dominant alpha rhythms observed in mammals in quiet and dark environments is not solely attributed to cholinergic pontine nuclei cells functioning as a 10 Hz pacemaker in the brainstem. It also involves the ability of the neocortex's cortical layers to generate traveling waves of alpha rhythms with waxing and waning characteristics. The utilization of alpha rhythms might have facilitated the shift of attention from external visual inputs to internal cognitive processes as an adaptation to thrive in dark environments. The evolution of alpha rhythms might trace back to the dinosaur era, suggesting that enhanced cortical connectivity linked to alpha bands could have facilitated the development of nocturnal awakening in the ancestors of mammals. In fishes, reptiles, and birds, the pallium lacks a cortical layer. However, there is a lack of research clearly observing dominant alpha rhythms in the pallium or organized nuclear structures in fishes, reptiles, or birds. Through convergent evolution, the pallium of birds, which exhibits cortex-like fiber architecture, has not only acquired advanced cognitive and motor abilities but also the capability to generate low-frequency oscillations (4-25 Hz) resembling alpha rhythms. This suggests that the origins of alpha rhythms might lie in the pallium of a common ancestor of birds and mammals.
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Affiliation(s)
- Takashi Shibata
- Department of Neurosurgery, Toyama University Hospital, Toyama, Japan
- Department of Neurosurgery, Toyama Nishi General Hospital, Toyama, Japan
| | - Noriaki Hattori
- Department of Rehabilitation, Toyama University Hospital, Toyama, Japan
| | - Hisao Nishijo
- Faculty of Human Sciences, University of East Asia, Yamaguchi, Japan
| | - Satoshi Kuroda
- Department of Neurosurgery, Toyama University Hospital, Toyama, Japan
| | - Kaoru Takakusaki
- The Research Center for Brain Function and Medical Engineering, Asahikawa Medical University, Asahikawa, Japan
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2
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Song J, Westover MB, Zhang R. A neural mass model for disturbance of alpha rhythm in the minimal hepatic encephalopathy. Mol Cell Neurosci 2024; 128:103918. [PMID: 38296121 DOI: 10.1016/j.mcn.2024.103918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/18/2024] [Accepted: 01/21/2024] [Indexed: 02/13/2024] Open
Abstract
One of the early markers of minimal hepatic encephalopathy (MHE) is the disruption of alpha rhythm observed in electroencephalogram (EEG) signals. However, the underlying mechanisms responsible for this occurrence remain poorly understood. To address this gap, we develop a novel biophysical model MHE-AWD-NCM, encompassing the communication dynamics between a cortical neuron population (CNP) and an astrocyte population (AP), aimed at investigating the relationship between alpha wave disturbance (AWD) and mechanistical principles, specifically concerning astrocyte-neuronal communication in the context of MHE. In addition, we introduce the concepts of peak power density and peak frequency within the alpha band as quantitative measures of AWD. Our model faithfully reproduces the characteristic EEG phenomenology during MHE and shows how impairments of communication between CNP and AP could promote AWD. The results suggest that the disruptions in feedback neurotransmission from AP to CNP, along with the inhibition of GABA uptake by AP from the extracellular space, contribute to the observed AWD. Moreover, we found that the variation of external excitatory stimuli on CNP may play a key role in AWD in MHE. Finally, the sensitivity analysis is also performed to assess the relative significance of above factors in influencing AWD. Our findings align with the physiological observations and provide a more comprehensive understanding of the complex interplay of astrocyte-neuronal communication that underlies the AWD observed in MHE, which potentially may help to explore the targeted therapeutic interventions for the early stage of hepatic encephalopathy.
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Affiliation(s)
- Jiangling Song
- The Medical Big Data Research Center, Northwest University, Xi'an, China
| | - M Brandon Westover
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Rui Zhang
- The Medical Big Data Research Center, Northwest University, Xi'an, China.
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3
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Tolin DF, O'Bryan EM, Davies CD, Diefenbach GJ, Johannesen J. Central and peripheral nervous system responses to chronic and paced hyperventilation in anxious and healthy subjects. Biol Psychol 2023; 176:108472. [PMID: 36481266 PMCID: PMC9839632 DOI: 10.1016/j.biopsycho.2022.108472] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 11/28/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022]
Abstract
The aim of the present study was to examine self-report, peripheral nervous system, and central nervous system correlates of naturally-occurring, chronic hyperventilation (HV, assessed by hypocapnia or low resting state low end-tidal CO2), and to examine the additional effect of acute, experimentally-induced HV in anxious and healthy participants. By identifying the biomarkers of anxiety-related chronic HV and examining responses to acute HV, we hope to identify meaningful, mechanistic targets for further treatment development. Seventy anxious patients and 34 healthy control participants completed electroencephalogram (EEG) and peripheral nervous system recording at baseline and following a paced breathing task. Diagnosis x baseline hypnocapnia group analyses indicated that anxious/hypocapnic patients exhibited greater nonspecific skin conductance response amplitude than did anxious/normocapnic patients, and the anxious group reported greater HV-related symptoms and anxiety sensitivity than did the control group. However, no EEG abnormalities were noted as a function of anxiety group or baseline hypocapnia status. Following paced HV, anxious patients (but not controls) exhibited an increase in left-frontal alpha 1 power. Hypocapnic, but not normocapnic, participants exhibited an increase in skin conductance levels. Anxious patients reported an increase in negative cognitive appraisals of HV symptoms, and anxious/hypocapnic participants reported an increase in affective responses to HV. Thus, chronic HV is associated with greater arousal, and increased self-reported and physiological sensitivity to paced HV. Patients who chronically hyperventilate appear to be more sensitive to respiratory distress, responding with higher levels of anxiety and poorer tolerance of the physiological sensations accompanying acute HV.
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Affiliation(s)
- David F Tolin
- Institute of Living, Hartford, CT, United States; Yale University School of Medicine, New Haven, CT, United States.
| | - Emily M O'Bryan
- Institute of Living, Hartford, CT, United States; Endicott College, Beverly, MA, United States
| | - Carolyn D Davies
- Institute of Living, Hartford, CT, United States; University of Massachusetts, Amherst, MA, United States
| | - Gretchen J Diefenbach
- Institute of Living, Hartford, CT, United States; Yale University School of Medicine, New Haven, CT, United States
| | - Jason Johannesen
- Yale University School of Medicine, New Haven, CT, United States
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Van de Steen F, Pinotsis D, Devos W, Colenbier N, Bassez I, Friston K, Marinazzo D. Dynamic causal modelling shows a prominent role of local inhibition in alpha power modulation in higher visual cortex. PLoS Comput Biol 2022; 18:e1009988. [PMID: 36574458 PMCID: PMC9829170 DOI: 10.1371/journal.pcbi.1009988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 01/09/2023] [Accepted: 12/16/2022] [Indexed: 12/29/2022] Open
Abstract
During resting-state EEG recordings, alpha activity is more prominent over the posterior cortex in eyes-closed (EC) conditions compared to eyes-open (EO). In this study, we characterized the difference in spectra between EO and EC conditions using dynamic causal modelling. Specifically, we investigated the role of intrinsic and extrinsic connectivity-within the visual cortex-in generating EC-EO alpha power differences over posterior electrodes. The primary visual cortex (V1) and the bilateral middle temporal visual areas (V5) were equipped with bidirectional extrinsic connections using a canonical microcircuit. The states of four intrinsically coupled subpopulations-within each occipital source-were also modelled. Using Bayesian model selection, we tested whether modulations of the intrinsic connections in V1, V5 or extrinsic connections (or a combination thereof) provided the best evidence for the data. In addition, using parametric empirical Bayes (PEB), we estimated group averages under the winning model. Bayesian model selection showed that the winning model contained both extrinsic connectivity modulations, as well as intrinsic connectivity modulations in all sources. The PEB analysis revealed increased extrinsic connectivity during EC. Overall, we found a reduction in the inhibitory intrinsic connections during EC. The results suggest that the intrinsic modulations in V5 played the most important role in producing EC-EO alpha differences, suggesting an intrinsic disinhibition in higher order visual cortex, during EC resting state.
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Affiliation(s)
- Frederik Van de Steen
- Department of Data Analysis, Ghent University, Ghent, Belgium
- Vrije Universiteit Brussel, AIMS laboratory, Brussel, Belgium
- The Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom
- * E-mail:
| | - Dimitris Pinotsis
- Centre for Mathematical Neuroscience and Psychology and Department of Psychology, City—University of London, London, United Kingdom
- The Picower Institute for Learning & Memory and Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, United States of America
| | - Wouter Devos
- Department of Data Analysis, Ghent University, Ghent, Belgium
| | | | - Iege Bassez
- Department of Data Analysis, Ghent University, Ghent, Belgium
| | - Karl Friston
- The Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom
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Ranasinghe KG, Verma P, Cai C, Xie X, Kudo K, Gao X, Lerner H, Mizuiri D, Strom A, Iaccarino L, La Joie R, Miller BL, Gorno-Tempini ML, Rankin KP, Jagust WJ, Vossel K, Rabinovici GD, Raj A, Nagarajan SS. Altered excitatory and inhibitory neuronal subpopulation parameters are distinctly associated with tau and amyloid in Alzheimer's disease. eLife 2022; 11:e77850. [PMID: 35616532 PMCID: PMC9217132 DOI: 10.7554/elife.77850] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 05/19/2022] [Indexed: 11/13/2022] Open
Abstract
Background Neuronal- and circuit-level abnormalities of excitation and inhibition are shown to be associated with tau and amyloid-beta (Aβ) in preclinical models of Alzheimer's disease (AD). These relationships remain poorly understood in patients with AD. Methods Using empirical spectra from magnetoencephalography and computational modeling (neural mass model), we examined excitatory and inhibitory parameters of neuronal subpopulations and investigated their specific associations to regional tau and Aβ, measured by positron emission tomography, in patients with AD. Results Patients with AD showed abnormal excitatory and inhibitory time-constants and neural gains compared to age-matched controls. Increased excitatory time-constants distinctly correlated with higher tau depositions while increased inhibitory time-constants distinctly correlated with higher Aβ depositions. Conclusions Our results provide critical insights about potential mechanistic links between abnormal neural oscillations and cellular correlates of impaired excitatory and inhibitory synaptic functions associated with tau and Aβ in patients with AD. Funding This study was supported by the National Institutes of Health grants: K08AG058749 (KGR), F32AG050434-01A1 (KGR), K23 AG038357 (KAV), P50 AG023501, P01 AG19724 (BLM), P50-AG023501 (BLM and GDR), R01 AG045611 (GDR); AG034570, AG062542 (WJ); NS100440 (SSN), DC176960 (SSN), DC017091 (SSN), AG062196 (SSN); a grant from John Douglas French Alzheimer's Foundation (KAV); grants from Larry L. Hillblom Foundation: 2015-A-034-FEL (KGR), 2019-A-013-SUP (KGR); grants from the Alzheimer's Association: AARG-21-849773 (KGR); PCTRB-13-288476 (KAV), and made possible by Part the CloudTM (ETAC-09-133596); a grant from Tau Consortium (GDR and WJJ), and a gift from the S. D. Bechtel Jr. Foundation.
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Affiliation(s)
- Kamalini G Ranasinghe
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
| | - Parul Verma
- Department of Radiology and Biomedical Imaging, University of California, San FranciscoSan FranciscoUnited States
| | - Chang Cai
- Department of Radiology and Biomedical Imaging, University of California, San FranciscoSan FranciscoUnited States
| | - Xihe Xie
- Department of Radiology and Biomedical Imaging, University of California, San FranciscoSan FranciscoUnited States
| | - Kiwamu Kudo
- Department of Radiology and Biomedical Imaging, University of California, San FranciscoSan FranciscoUnited States
- Medical Imaging Business Center, Ricoh CompanyKanazawaJapan
| | - Xiao Gao
- Department of Radiology and Biomedical Imaging, University of California, San FranciscoSan FranciscoUnited States
| | - Hannah Lerner
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
| | - Danielle Mizuiri
- Department of Radiology and Biomedical Imaging, University of California, San FranciscoSan FranciscoUnited States
| | - Amelia Strom
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
| | - Leonardo Iaccarino
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
| | - Renaud La Joie
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
| | - Bruce L Miller
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
| | - Maria Luisa Gorno-Tempini
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
| | - Katherine P Rankin
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
| | - William J Jagust
- Helen Wills Neuroscience Institute, University of California, BerkeleyBerkeleyUnited States
| | - Keith Vossel
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
- Mary S. Easton Center for Alzheimer’s Disease Research, Department of Neurology, David Geffen School of Medicine, University of California, Los AngelesLos AngelesUnited States
| | - Gil D Rabinovici
- Memory and Aging Center, Department of Neurology, University of California, San FranciscoSan FranciscoUnited States
- Department of Radiology and Biomedical Imaging, University of California, San FranciscoSan FranciscoUnited States
| | - Ashish Raj
- Department of Radiology and Biomedical Imaging, University of California, San FranciscoSan FranciscoUnited States
| | - Srikantan S Nagarajan
- Department of Radiology and Biomedical Imaging, University of California, San FranciscoSan FranciscoUnited States
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Evertz R, Hicks DG, Liley DTJ. Alpha blocking and 1/fβ spectral scaling in resting EEG can be accounted for by a sum of damped alpha band oscillatory processes. PLoS Comput Biol 2022; 18:e1010012. [PMID: 35427355 PMCID: PMC9045666 DOI: 10.1371/journal.pcbi.1010012] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 04/27/2022] [Accepted: 03/11/2022] [Indexed: 11/18/2022] Open
Abstract
The dynamical and physiological basis of alpha band activity and 1/fβ noise in the EEG are the subject of continued speculation. Here we conjecture, on the basis of empirical data analysis, that both of these features may be economically accounted for through a single process if the resting EEG is conceived of being the sum of multiple stochastically perturbed alpha band damped linear oscillators with a distribution of dampings (relaxation rates). The modulation of alpha-band and 1/fβ noise activity by changes in damping is explored in eyes closed (EC) and eyes open (EO) resting state EEG. We aim to estimate the distribution of dampings by solving an inverse problem applied to EEG power spectra. The characteristics of the damping distribution are examined across subjects, sensors and recording condition (EC/EO). We find that there are robust changes in the damping distribution between EC and EO recording conditions across participants. The estimated damping distributions are found to be predominantly bimodal, with the number and position of the modes related to the sharpness of the alpha resonance and the scaling (β) of the power spectrum (1/fβ). The results suggest that there exists an intimate relationship between resting state alpha activity and 1/fβ noise with changes in both governed by changes to the damping of the underlying alpha oscillatory processes. In particular, alpha-blocking is observed to be the result of the most weakly damped distribution mode becoming more heavily damped. The results suggest a novel way of characterizing resting EEG power spectra and provides new insight into the central role that damped alpha-band activity may play in characterising the spatio-temporal features of resting state EEG. The resting human electroencephalogram (EEG) exhibits two dominant spectral features: the alpha rhythm (8–13 Hz) and its associated attenuation between eyes-closed and eyes-open resting state (alpha blocking), and the 1/fβ scaling of the power spectrum. While these phenomena are well studied a thorough understanding of their respective generative processes remains elusive. By employing a theoretical approach that follows from neural population models of EEG we demonstrate that it is possible to economically account for both of these phenomena using a singular mechanistic framework: resting EEG is assumed to arise from the summed activity of multiple uncorrelated, stochastically driven, damped alpha band linear oscillatory processes having a distribution of relaxation rates or dampings. By numerically estimating these damping distributions from eyes-closed and eyes-open EEG data, in a total of 136 participants, it is found that such damping distributions are predominantly bimodal in shape. The most weakly damped mode is found to account for alpha band power, with alpha blocking being driven by an increase in the damping of this weakly damped mode, whereas the second, and more heavily damped mode, is able to explain 1/fβ scaling present in the resting state EEG spectra.
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Affiliation(s)
- Rick Evertz
- Optical Sciences Centre, Swinburne University of Technology, Hawthorn, Victoria, Australia
- Department of Physics and Astronomy, Swinburne University of Technology, Hawthorn, Victoria, Australia
- * E-mail: (RE); (DGH); (DTJL)
| | - Damien G. Hicks
- Optical Sciences Centre, Swinburne University of Technology, Hawthorn, Victoria, Australia
- Department of Physics and Astronomy, Swinburne University of Technology, Hawthorn, Victoria, Australia
- Bioinformatics Division, Walter & Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- * E-mail: (RE); (DGH); (DTJL)
| | - David T. J. Liley
- Department of Medicine, University of Melbourne, Parkville, Victoria, Australia
- * E-mail: (RE); (DGH); (DTJL)
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On the Operational Utility of Measures of Multichannel EEGs. ENTROPY 2021; 23:e23111434. [PMID: 34828132 PMCID: PMC8617715 DOI: 10.3390/e23111434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 10/12/2021] [Accepted: 10/27/2021] [Indexed: 11/16/2022]
Abstract
Multichannel EEGs were obtained from healthy participants in the eyes-closed no-task condition and in the eyes-open condition (where the alpha component is typically abolished). EEG dynamics in the two conditions were quantified with two related binary Lempel–Ziv measures of the first principal component, and with three measures of integrated information, including the more recently proposed integrated synergy. Both integrated information and integrated synergy with model order p=1 had greater values in the eyes-closed condition. When the model order of integrated synergy was determined with the Bayesian Information Criterion, this pattern was reversed, and in line with the other measures, integrated synergy was greater in the eyes-open condition. Eyes-open versus eyes-closed separation was quantified by calculating the between-condition effect size. The Lempel–Ziv complexity of the first principal component showed greater separation than the measures of integrated information.
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Komiyama T, Goya R, Aoyama C, Yokota Y, Naruse Y, Shimegi S. The combination of acute exercise and eye closure has a synergistic effect on alpha activity. Sci Rep 2021; 11:20186. [PMID: 34642438 PMCID: PMC8511023 DOI: 10.1038/s41598-021-99783-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 09/28/2021] [Indexed: 12/02/2022] Open
Abstract
Acute aerobic exercise increases the brain cortical activity in alpha frequency. Eye closure also increases alpha activity. However, whether the two have an additive or a synergistic effect on alpha activity has never been explored. This study observed electroencephalography (EEG) from fifteen participants seated on the cycle ergometer before, during, and after a cycling exercise with the eyes open and with them closed. Exercise intensity was set to a target heart rate (120-130 bpm), corresponding to light-to-moderate intensity exercise. Each epoch was 6 min and the last 4 min (eyes closed in the first 2 min and eyes open in the second 2 min) were analyzed. The EEG power spectrum densities were calculated for alpha frequency band activity (8-13 Hz). At rest, alpha activity was significantly greater with the eyes closed than open. Exercise significantly increased alpha activity in both eye conditions. More importantly, in the occipital site, the alpha-increasing effect of their combination was significantly greater than the sum of the effect of each, showing a synergistic effect. We concluded that acute light-to-moderate intensity exercise with the eyes closed has a synergistic effect on alpha activity.
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Affiliation(s)
- Takaaki Komiyama
- Center for Education in Liberal Arts and Sciences, Osaka University, 1-16 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Ryoma Goya
- Graduate School of Frontier of Biosciences, Osaka University, Toyonaka, Osaka, Japan
| | - Chisa Aoyama
- Graduate School of Medicine, Osaka University, Toyonaka, Osaka, Japan
| | - Yusuke Yokota
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology, Osaka University, Kobe, Japan
| | - Yasushi Naruse
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology, Osaka University, Kobe, Japan
| | - Satoshi Shimegi
- Center for Education in Liberal Arts and Sciences, Osaka University, 1-16 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.
- Graduate School of Frontier of Biosciences, Osaka University, Toyonaka, Osaka, Japan.
- Graduate School of Medicine, Osaka University, Toyonaka, Osaka, Japan.
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology, Osaka University, Kobe, Japan.
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