1
|
Bandarabadi M, Prouvot Bouvier PH, Corsi G, Tafti M. The paradox of REM sleep: Seven decades of evolution. Sleep Med Rev 2024; 74:101918. [PMID: 38457935 DOI: 10.1016/j.smrv.2024.101918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 02/26/2024] [Indexed: 03/10/2024]
Affiliation(s)
- Mojtaba Bandarabadi
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland.
| | | | - Giorgio Corsi
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Mehdi Tafti
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
2
|
Bandarabadi M, Li S, Aeschlimann L, Colombo G, Tzanoulinou S, Tafti M, Becchetti A, Boutrel B, Vassalli A. Inactivation of hypocretin receptor-2 signaling in dopaminergic neurons induces hyperarousal and enhanced cognition but impaired inhibitory control. Mol Psychiatry 2023:10.1038/s41380-023-02329-z. [PMID: 38123729 DOI: 10.1038/s41380-023-02329-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 11/09/2023] [Accepted: 11/15/2023] [Indexed: 12/23/2023]
Abstract
Hypocretin/Orexin (HCRT/OX) and dopamine (DA) are both key effectors of salience processing, reward and stress-related behaviors and motivational states, yet their respective roles and interactions are poorly delineated. We inactivated HCRT-to-DA connectivity by genetic disruption of Hypocretin receptor-1 (Hcrtr1), Hypocretin receptor-2 (Hcrtr2), or both receptors (Hcrtr1&2) in DA neurons and analyzed the consequences on vigilance states, brain oscillations and cognitive performance in freely behaving mice. Unexpectedly, loss of Hcrtr2, but not Hcrtr1 or Hcrtr1&2, induced a dramatic increase in theta (7-11 Hz) electroencephalographic (EEG) activity in both wakefulness and rapid-eye-movement sleep (REMS). DAHcrtr2-deficient mice spent more time in an active (or theta activity-enriched) substate of wakefulness, and exhibited prolonged REMS. Additionally, both wake and REMS displayed enhanced theta-gamma phase-amplitude coupling. The baseline waking EEG of DAHcrtr2-deficient mice exhibited diminished infra-theta, but increased theta power, two hallmarks of EEG hyperarousal, that were however uncoupled from locomotor activity. Upon exposure to novel, either rewarding or stress-inducing environments, DAHcrtr2-deficient mice featured more pronounced waking theta and fast-gamma (52-80 Hz) EEG activity surges compared to littermate controls, further suggesting increased alertness. Cognitive performance was evaluated in an operant conditioning paradigm, which revealed that DAHcrtr2-ablated mice manifest faster task acquisition and higher choice accuracy under increasingly demanding task contingencies. However, the mice concurrently displayed maladaptive patterns of reward-seeking, with behavioral indices of enhanced impulsivity and compulsivity. None of the EEG changes observed in DAHcrtr2-deficient mice were seen in DAHcrtr1-ablated mice, which tended to show opposite EEG phenotypes. Our findings establish a clear genetically-defined link between monosynaptic HCRT-to-DA neurotransmission and theta oscillations, with a differential and novel role of HCRTR2 in theta-gamma cross-frequency coupling, attentional processes, and executive functions, relevant to disorders including narcolepsy, attention-deficit/hyperactivity disorder, and Parkinson's disease.
Collapse
Affiliation(s)
- Mojtaba Bandarabadi
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Sha Li
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Lea Aeschlimann
- Centre for Psychiatric Neuroscience, Department of Psychiatry, The Lausanne University Hospital, Lausanne, Switzerland
| | - Giulia Colombo
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy
| | | | - Mehdi Tafti
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Andrea Becchetti
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy
| | - Benjamin Boutrel
- Centre for Psychiatric Neuroscience, Department of Psychiatry, The Lausanne University Hospital, Lausanne, Switzerland
| | - Anne Vassalli
- Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland.
| |
Collapse
|
3
|
Czekus C, Steullet P, Orero López A, Bozic I, Rusterholz T, Bandarabadi M, Do KQ, Gutierrez Herrera C. Alterations in TRN-anterodorsal thalamocortical circuits affect sleep architecture and homeostatic processes in oxidative stress vulnerable Gclm -/- mice. Mol Psychiatry 2022; 27:4394-4406. [PMID: 35902628 PMCID: PMC9734061 DOI: 10.1038/s41380-022-01700-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 06/22/2022] [Accepted: 07/01/2022] [Indexed: 12/14/2022]
Abstract
Schizophrenia is associated with alterations of sensory integration, cognitive processing and both sleep architecture and sleep oscillations in mouse models and human subjects, possibly through changes in thalamocortical dynamics. Oxidative stress (OxS) damage, including inflammation and the impairment of fast-spiking gamma-aminobutyric acid neurons have been hypothesized as a potential mechanism responsible for the onset and development of schizophrenia. Yet, the link between OxS and perturbation of thalamocortical dynamics and sleep remains unclear. Here, we sought to investigate the effects of OxS on sleep regulation by characterizing the dynamics of thalamocortical networks across sleep-wake states in a mouse model with a genetic deletion of the modifier subunit of glutamate-cysteine ligase (Gclm knockout, KO) using high-density electrophysiology in freely-moving mice. We found that Gcml KO mice exhibited a fragmented sleep architecture and impaired sleep homeostasis responses as revealed by the increased NREM sleep latencies, decreased slow-wave activities and spindle rate after sleep deprivation. These changes were associated with altered bursting activity and firing dynamics of neurons from the thalamic reticularis nucleus, anterior cingulate and anterodorsal thalamus. Administration of N-acetylcysteine (NAC), a clinically relevant antioxidant, rescued the sleep fragmentation and spindle rate through a renormalization of local neuronal dynamics in Gclm KO mice. Collectively, these findings provide novel evidence for a link between OxS and the deficits of frontal TC network dynamics as a possible mechanism underlying sleep abnormalities and impaired homeostatic responses observed in schizophrenia.
Collapse
Affiliation(s)
- Christina Czekus
- grid.411656.10000 0004 0479 0855Center for Experimental Neurology, Department of Neurology, Inselspital University Hospital, Bern, Switzerland
| | - Pascal Steullet
- grid.8515.90000 0001 0423 4662Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Site de Cery, CH-1008 Prilly-Lausanne, Switzerland
| | - Albert Orero López
- grid.411656.10000 0004 0479 0855Center for Experimental Neurology, Department of Neurology, Inselspital University Hospital, Bern, Switzerland
| | - Ivan Bozic
- grid.5734.50000 0001 0726 5157Department for Biomedical Research, University of Bern, Bern, Switzerland
| | - Thomas Rusterholz
- grid.411656.10000 0004 0479 0855Center for Experimental Neurology, Department of Neurology, Inselspital University Hospital, Bern, Switzerland
| | - Mojtaba Bandarabadi
- grid.411656.10000 0004 0479 0855Center for Experimental Neurology, Department of Neurology, Inselspital University Hospital, Bern, Switzerland ,grid.9851.50000 0001 2165 4204Present Address: Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Kim Q. Do
- grid.8515.90000 0001 0423 4662Center for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, Site de Cery, CH-1008 Prilly-Lausanne, Switzerland
| | - Carolina Gutierrez Herrera
- Center for Experimental Neurology, Department of Neurology, Inselspital University Hospital, Bern, Switzerland. .,Department for Biomedical Research, University of Bern, Bern, Switzerland.
| |
Collapse
|
4
|
Bandarabadi M, Herrera CG, Gent TC, Bassetti C, Schindler K, Adamantidis AR. A role for spindles in the onset of rapid eye movement sleep. Nat Commun 2020; 11:5247. [PMID: 33067436 PMCID: PMC7567828 DOI: 10.1038/s41467-020-19076-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 09/21/2020] [Indexed: 12/17/2022] Open
Abstract
Sleep spindle generation classically relies on an interplay between the thalamic reticular nucleus (TRN), thalamo-cortical (TC) relay cells and cortico-thalamic (CT) feedback during non-rapid eye movement (NREM) sleep. Spindles are hypothesized to stabilize sleep, gate sensory processing and consolidate memory. However, the contribution of non-sensory thalamic nuclei in spindle generation and the role of spindles in sleep-state regulation remain unclear. Using multisite thalamic and cortical LFP/unit recordings in freely behaving mice, we show that spike-field coupling within centromedial and anterodorsal (AD) thalamic nuclei is as strong as for TRN during detected spindles. We found that spindle rate significantly increases before the onset of rapid eye movement (REM) sleep, but not wakefulness. The latter observation is consistent with our finding that enhancing spontaneous activity of TRN cells or TRN-AD projections using optogenetics increase spindle rate and transitions to REM sleep. Together, our results extend the classical TRN-TC-CT spindle pathway to include non-sensory thalamic nuclei and implicate spindles in the onset of REM sleep. During NREM sleep, spindles emerge from thalamocortical interactions. Here the authors carry out multisite thalamic and cortical recordings in freely behaving mice, to investigate the role of other non-classical thalamic sites in sleep spindle generation.
Collapse
Affiliation(s)
- Mojtaba Bandarabadi
- Department of Neurology, Zentrum für Experimentelle Neurologie, Inselspital University Hospital Bern, Bern, Switzerland.,Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital University Hospital Bern, Bern, Switzerland.,Department of Biomedical Sciences, University of Lausanne, Lausanne, Switzerland
| | - Carolina Gutierrez Herrera
- Department of Neurology, Zentrum für Experimentelle Neurologie, Inselspital University Hospital Bern, Bern, Switzerland.,Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Thomas C Gent
- Department of Neurology, Zentrum für Experimentelle Neurologie, Inselspital University Hospital Bern, Bern, Switzerland.,Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Claudio Bassetti
- Department of Neurology, Zentrum für Experimentelle Neurologie, Inselspital University Hospital Bern, Bern, Switzerland.,Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital University Hospital Bern, Bern, Switzerland
| | - Kaspar Schindler
- Department of Neurology, Zentrum für Experimentelle Neurologie, Inselspital University Hospital Bern, Bern, Switzerland.,Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital University Hospital Bern, Bern, Switzerland
| | - Antoine R Adamantidis
- Department of Neurology, Zentrum für Experimentelle Neurologie, Inselspital University Hospital Bern, Bern, Switzerland. .,Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital University Hospital Bern, Bern, Switzerland. .,Department of Biomedical Research, University of Bern, Bern, Switzerland.
| |
Collapse
|
5
|
Oesch LT, Gazea M, Gent TC, Bandarabadi M, Gutierrez Herrera C, Adamantidis AR. REM sleep stabilizes hypothalamic representation of feeding behavior. Proc Natl Acad Sci U S A 2020; 117:19590-19598. [PMID: 32732431 PMCID: PMC7430996 DOI: 10.1073/pnas.1921909117] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
During rapid eye movement (REM) sleep, behavioral unresponsiveness contrasts strongly with intense brain-wide neural network dynamics. Yet, the physiological functions of this cellular activation remain unclear. Using in vivo calcium imaging in freely behaving mice, we found that inhibitory neurons in the lateral hypothalamus (LHvgat) show unique activity patterns during feeding that are reactivated during REM, but not non-REM, sleep. REM sleep-specific optogenetic silencing of LHvgat cells induced a reorganization of these activity patterns during subsequent feeding behaviors accompanied by decreased food intake. Our findings provide evidence for a role for REM sleep in the maintenance of cellular representations of feeding behavior.
Collapse
Affiliation(s)
- Lukas T Oesch
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, CH-3010 Bern, Switzerland
- Department of Biomedical Research, University of Bern, CH-3010 Bern, Switzerland
| | - Mary Gazea
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, CH-3010 Bern, Switzerland
- Department of Biomedical Research, University of Bern, CH-3010 Bern, Switzerland
| | - Thomas C Gent
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, CH-3010 Bern, Switzerland
- Department of Biomedical Research, University of Bern, CH-3010 Bern, Switzerland
| | - Mojtaba Bandarabadi
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, CH-3010 Bern, Switzerland
- Department of Biomedical Research, University of Bern, CH-3010 Bern, Switzerland
| | - Carolina Gutierrez Herrera
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, CH-3010 Bern, Switzerland
- Department of Biomedical Research, University of Bern, CH-3010 Bern, Switzerland
| | - Antoine R Adamantidis
- Zentrum für Experimentelle Neurologie, Department of Neurology, Inselspital University Hospital Bern, CH-3010 Bern, Switzerland;
- Department of Biomedical Research, University of Bern, CH-3010 Bern, Switzerland
| |
Collapse
|
6
|
|
7
|
Pace M, Colombi I, Falappa M, Freschi A, Bandarabadi M, Armirotti A, Encarnación BM, Adamantidis AR, Amici R, Cerri M, Chiappalone M, Tucci V. Loss of Snord116 alters cortical neuronal activity in mice: a preclinical investigation of Prader–Willi syndrome. Hum Mol Genet 2020; 29:2051-2064. [DOI: 10.1093/hmg/ddaa084] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/26/2020] [Accepted: 04/27/2020] [Indexed: 12/27/2022] Open
Abstract
Abstract
Prader–Willi syndrome (PWS) is a neurodevelopmental disorder that is characterized by metabolic alteration and sleep abnormalities mostly related to rapid eye movement (REM) sleep disturbances. The disease is caused by genomic imprinting defects that are inherited through the paternal line. Among the genes located in the PWS region on chromosome 15 (15q11-q13), small nucleolar RNA 116 (Snord116) has been previously associated with intrusions of REM sleep into wakefulness in humans and mice. Here, we further explore sleep regulation of PWS by reporting a study with PWScrm+/p− mouse line, which carries a paternal deletion of Snord116. We focused our study on both macrostructural electrophysiological components of sleep, distributed among REMs and nonrapid eye movements. Of note, here, we study a novel electroencephalography (EEG) graphoelements of sleep for mouse studies, the well-known spindles. EEG biomarkers are often linked to the functional properties of cortical neurons and can be instrumental in translational studies. Thus, to better understand specific properties, we isolated and characterized the intrinsic activity of cortical neurons using in vitro microelectrode array. Our results confirm that the loss of Snord116 gene in mice influences specific properties of REM sleep, such as theta rhythms and, for the first time, the organization of REM episodes throughout sleep–wake cycles. Moreover, the analysis of sleep spindles present novel specific phenotype in PWS mice, indicating that a new catalog of sleep biomarkers can be informative in preclinical studies of PWS.
Collapse
Affiliation(s)
- Marta Pace
- Genetics and Epigenetics of Behaviour (GEB), Istituto Italiano di Tecnologia (IIT), Genova 16163, Italy
| | - Ilaria Colombi
- Genetics and Epigenetics of Behaviour (GEB), Istituto Italiano di Tecnologia (IIT), Genova 16163, Italy
- Dipartimento di Neuroscienze, Riabilitazione, Oftalmologia, Genetica e Scienze Materno-Infantili (DINOGMI), Università degli Studi di Genova, Genova 16132, Italy
| | - Matteo Falappa
- Genetics and Epigenetics of Behaviour (GEB), Istituto Italiano di Tecnologia (IIT), Genova 16163, Italy
- Dipartimento di Neuroscienze, Riabilitazione, Oftalmologia, Genetica e Scienze Materno-Infantili (DINOGMI), Università degli Studi di Genova, Genova 16132, Italy
| | - Andrea Freschi
- Genetics and Epigenetics of Behaviour (GEB), Istituto Italiano di Tecnologia (IIT), Genova 16163, Italy
| | - Mojtaba Bandarabadi
- Centre for Experimental Neurology, Department of Neurology, Inselspital University Hospital, University of Bern, Bern 3010, Switzerland
| | - Andrea Armirotti
- Analytical Chemistry Facility, Istituto Italiano di Tecnologia (IIT), Genova 16163, Italy
| | | | - Antoine R Adamantidis
- Centre for Experimental Neurology, Department of Neurology, Inselspital University Hospital, University of Bern, Bern 3010, Switzerland
- Department of Clinical Research, Inselspital University Hospital, University of Bern, Bern 3010, Switzerland
| | - Roberto Amici
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum—University of Bologna, Bologna 40126, Italy
| | - Matteo Cerri
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum—University of Bologna, Bologna 40126, Italy
| | - Michela Chiappalone
- Rehab Technologies, Istituto Italiano di Tecnologia (IIT), Genova 16163, Italy
| | - Valter Tucci
- Genetics and Epigenetics of Behaviour (GEB), Istituto Italiano di Tecnologia (IIT), Genova 16163, Italy
| |
Collapse
|
8
|
Bandarabadi M, Gast H, Rummel C, Bassetti C, Adamantidis A, Schindler K, Zubler F. Assessing Epileptogenicity Using Phase-Locked High Frequency Oscillations: A Systematic Comparison of Methods. Front Neurol 2019; 10:1132. [PMID: 31749757 PMCID: PMC6842969 DOI: 10.3389/fneur.2019.01132] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 10/10/2019] [Indexed: 01/21/2023] Open
Abstract
High frequency oscillations (HFOs) are traditional biomarkers to identify the epileptogenic tissue during presurgical evaluation in pharmacoresistant epileptic patients. Recently, the resection of brain tissue exhibiting coupling between the amplitude of HFOs and the phase of low frequencies demonstrated a more favorable surgical outcome. Here we compare the predictive value of ictal HFOs and four methods for quantifying the ictal phase-amplitude coupling, namely mean vector length, phase-locked high gamma, phase locking value, and modulation index (MI). We analyzed 32 seizures from 16 patients to identify the channels that exhibit HFOs and phase-locked HFOs during seizures. We compared the resection ratio, defined as the percentage of channels exhibiting coupling located in the resected tissue, with the postsurgical outcome. We found that the MI is the only method to show a significant difference between the resection ratios of patients with good and poor outcomes. We further show that the whole seizure, not only the onset, is critical to assess epileptogenicity using the phase-locked HFOs. We postulate that the superiority of MI stems from its capacity to assess coupling of discrete HFO events and its independence from the HFO power. These results confirm that quantitative analysis of HFOs can boost presurgical evaluation and indicate the paramount importance of algorithm selection for clinical applications.
Collapse
Affiliation(s)
- Mojtaba Bandarabadi
- Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland.,Department of Neurology, Center for Experimental Neurology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Heidemarie Gast
- Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Christian Rummel
- Support Center for Advanced Neuroimaging (SCAN), University Institute for Diagnostic and Interventional Neuroradiology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Claudio Bassetti
- Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland.,Department of Neurology, Center for Experimental Neurology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Antoine Adamantidis
- Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland.,Department of Neurology, Center for Experimental Neurology, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Kaspar Schindler
- Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Frederic Zubler
- Department of Neurology, Sleep-Wake-Epilepsy Center, Inselspital, University Hospital Bern, University of Bern, Bern, Switzerland
| |
Collapse
|
9
|
Miladinović Đ, Muheim C, Bauer S, Spinnler A, Noain D, Bandarabadi M, Gallusser B, Krummenacher G, Baumann C, Adamantidis A, Brown SA, Buhmann JM. SPINDLE: End-to-end learning from EEG/EMG to extrapolate animal sleep scoring across experimental settings, labs and species. PLoS Comput Biol 2019; 15:e1006968. [PMID: 30998681 PMCID: PMC6490936 DOI: 10.1371/journal.pcbi.1006968] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 04/30/2019] [Accepted: 03/20/2019] [Indexed: 11/18/2022] Open
Abstract
Understanding sleep and its perturbation by environment, mutation, or medication remains a central problem in biomedical research. Its examination in animal models rests on brain state analysis via classification of electroencephalographic (EEG) signatures. Traditionally, these states are classified by trained human experts by visual inspection of raw EEG recordings, which is a laborious task prone to inter-individual variability. Recently, machine learning approaches have been developed to automate this process, but their generalization capabilities are often insufficient, especially across animals from different experimental studies. To address this challenge, we crafted a convolutional neural network-based architecture to produce domain invariant predictions, and furthermore integrated a hidden Markov model to constrain state dynamics based upon known sleep physiology. Our method, which we named SPINDLE (Sleep Phase Identification with Neural networks for Domain-invariant LEearning) was validated using data of four animal cohorts from three independent sleep labs, and achieved average agreement rates of 99%, 98%, 93%, and 97% with scorings from five human experts from different labs, essentially duplicating human capability. It generalized across different genetic mutants, surgery procedures, recording setups and even different species, far exceeding state-of-the-art solutions that we tested in parallel on this task. Moreover, we show that these scored data can be processed for downstream analyzes identical to those from human-scored data, in particular by demonstrating the ability to detect mutation-induced sleep alteration. We provide to the scientific community free usage of SPINDLE and benchmarking datasets as an online server at https://sleeplearning.ethz.ch. Our aim is to catalyze high-throughput and well-standardized experimental studies in order to improve our understanding of sleep.
Collapse
Affiliation(s)
- Đorđe Miladinović
- Department of Computer Science, ETH Zurich, Zürich, Switzerland
- Max Planck Institute for Intelligent Systems, Tübingen, Germany
| | - Christine Muheim
- Chronobiology and Sleep Research Group, University of Zurich, Zürich, Switzerland
- Department of Biomedical Sciences, Washington State University, Spokane, Washington, United States of America
| | - Stefan Bauer
- Department of Computer Science, ETH Zurich, Zürich, Switzerland
- Max Planck Institute for Intelligent Systems, Tübingen, Germany
| | - Andrea Spinnler
- Chronobiology and Sleep Research Group, University of Zurich, Zürich, Switzerland
| | - Daniela Noain
- Department of Neurology, University Hospital Zurich, Zürich, Switzerland
| | | | | | | | - Christian Baumann
- Department of Neurology, University Hospital Zurich, Zürich, Switzerland
| | | | - Steven A. Brown
- Chronobiology and Sleep Research Group, University of Zurich, Zürich, Switzerland
| | | |
Collapse
|
10
|
Luca G, Bandarabadi M, Konofal E, Lecendreux M, Ferrié L, Figadère B, Tafti M. Lauflumide (NLS-4) Is a New Potent Wake-Promoting Compound. Front Neurosci 2018; 12:519. [PMID: 30158846 PMCID: PMC6104159 DOI: 10.3389/fnins.2018.00519] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 07/11/2018] [Indexed: 11/13/2022] Open
Abstract
Psychostimulants are used for the treatment of excessive daytime sleepiness in a wide range of sleep disorders as well as in attention deficit hyperactivity disorder or cognitive impairment in neuropsychiatric disorders. Here, we tested in mice the wake-promoting properties of NLS-4 and its effects on the following sleep as compared with those of modafinil and vehicle. C57BL/6J mice were intraperitoneally injected with vehicle, NLS-4 (64 mg/kg), or modafinil (150 mg/kg) at light onset. EEG and EMG were recorded continuously for 24 h after injections and vigilance states as well as EEG power densities were analyzed. NLS-4 at 64 mg/kg induced significantly longer wakefulness duration than modafinil at 150 mg/kg. Although no significant sleep rebound was observed after sleep onset for both treatments as compared with their vehicles, modafinil-treated mice showed significantly more NREM sleep when compared to NLS-4. Spectral analysis of the NREM EEG after NLS-4 treatment indicated an increased power density in delta activity (0.75–3.5 Hz) and a decreased power in theta frequency range (6.25–7.25 Hz), while there was no differences after modafinil treatment. Also, time course analysis of the delta activity showed a significant increase only during the first 2 time intervals of sleep after NLS-4 treatment, while delta power was increased during the first 9 time intervals after modafinil. Our results indicate that NLS-4 is a highly potent wake-promoting drug with no sign of hypersomnia rebound. As opposed to modafinil, recovery sleep after NLS-4 treatment is characterized by less NREM amount and delta activity, suggesting a lower need for recovery despite longer drug-induced wakefulness.
Collapse
Affiliation(s)
- Gianina Luca
- Faculty of Biology and Medicine, Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland.,Centre Neuchâtelois de Psychiatrie, Neuchâtel, Switzerland
| | - Mojtaba Bandarabadi
- Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Eric Konofal
- Pediatric Sleep Disorders Center, AP-HP, Robert Debre Hospital, Paris, France
| | - Michel Lecendreux
- Pediatric Sleep Disorders Center, AP-HP, Robert Debre Hospital, Paris, France.,AP-HP, Pediatric Sleep Center and National Reference Centre for Orphan Diseases, Narcolepsy, Idiopathic Hypersomnia and Kleine-Levin Syndrome (CNR Narcolepsie-Hypersomnie), CHU Robert-Debre, Paris, France
| | - Laurent Ferrié
- BioCIS, Université Paris-Sud, CNRS, Université Paris Saclay, Châtenay-Malabry, France
| | - Bruno Figadère
- BioCIS, Université Paris-Sud, CNRS, Université Paris Saclay, Châtenay-Malabry, France
| | - Mehdi Tafti
- Faculty of Biology and Medicine, Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland.,Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
11
|
Abstract
Slow-waves (0.5 - 4 Hz) predominate in the cortical electroencephalogram during non-rapid eye movement (NREM) sleep in mammals. They reflect the synchronization of large neuronal ensembles alternating between active (UP) and quiescent (Down) states and propagating along the neocortex. The thalamic contribution to cortical UP-states and sleep modulation remains unclear. Here we show that spontaneous firing of centromedial thalamus (CMT) neurons in mice is phase advanced to global cortical UP-states and NREM–wake transitions. Tonic optogenetic activation of CMT neurons induces NREM–wake transitions, whereas burst activation mimics UP-states in the cingulate cortex (CING) and enhances brain-wide synchrony of cortical slow-waves during sleep, through a relay in the antero-dorsal thalamus (AD). Finally, we demonstrate that CMT and AD relay neurons promote sleep recovery. These findings suggest that the firing pattern of CMT neurons can modulate brain-wide cortical activity during sleep and provides dual control of sleep-wake states.
Collapse
Affiliation(s)
- Thomas C Gent
- Centre for Experimental Neurology, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
| | - Mojtaba Bandarabadi
- Centre for Experimental Neurology, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
| | - Carolina Gutierrez Herrera
- Centre for Experimental Neurology, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
| | - Antoine R Adamantidis
- Centre for Experimental Neurology, Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland. .,Department of Biomedical Research (DBMR), Inselspital University Hospital Bern, University of Bern, Bern, Switzerland.
| |
Collapse
|
12
|
Facchin L, Schöne C, Mensen A, Bandarabadi M, Schindler K, Adamantidis A, Bassetti C. 0073 Optogenetic Control Of Sleep Slow Waves To Improve Recovery After Ischemic Stroke. Sleep 2018. [DOI: 10.1093/sleep/zsy061.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- L Facchin
- Centre for Experimental Neurology, Inselspital University Hospital, Bern, SWITZERL
| | - C Schöne
- Centre for Experimental Neurology, Inselspital University Hospital, Bern, SWITZERL
| | - A Mensen
- Department for Clinical Research, Inselspital University Hospital, Bern, SWITZERL
| | - M Bandarabadi
- Centre for Experimental Neurology, Inselspital University Hospital, Bern, SWITZERL
| | - K Schindler
- Department for Clinical Research, Inselspital University Hospital, Bern, SWITZERL
| | - A Adamantidis
- Centre for Experimental Neurology, Inselspital University Hospital, Bern, SWITZERL
| | - C Bassetti
- Centre for Experimental Neurology, Inselspital University Hospital, Bern, SWITZERL
| |
Collapse
|
13
|
Gent T, Bandarabadi M, Gutierrez Herrera C, Adamantidis A. Centromedial thalamus (CMT) control of cortical state during sleep. Sleep Med 2017. [DOI: 10.1016/j.sleep.2017.11.319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
14
|
Zubler F, Steimer A, Kurmann R, Bandarabadi M, Novy J, Gast H, Oddo M, Schindler K, Rossetti AO. EEG synchronization measures are early outcome predictors in comatose patients after cardiac arrest. Clin Neurophysiol 2017; 128:635-642. [PMID: 28235724 DOI: 10.1016/j.clinph.2017.01.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 01/22/2017] [Accepted: 01/24/2017] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Outcome prognostication in comatose patients after cardiac arrest (CA) remains a major challenge. Here we investigated the prognostic value of combinations of linear and non-linear bivariate EEG synchronization measures. METHODS 94 comatose patients with EEG within 24h after CA were included. Clinical outcome was assessed at 3months using the Cerebral Performance Categories (CPC). EEG synchronization between the left and right parasagittal, and between the frontal and parietal brain regions was assessed with 4 different quantitative measures (delta power asymmetry, cross-correlation, mutual information, and transfer entropy). 2/3 of patients were used to assess the predictive power of all possible combinations of these eight features (4 measures×2 directions) using cross-validation. The predictive power of the best combination was tested on the remaining 1/3 of patients. RESULTS The best combination for prognostication consisted of 4 of the 8 features, and contained linear and non-linear measures. Predictive power for poor outcome (CPC 3-5), measured with the area under the ROC curve, was 0.84 during cross-validation, and 0.81 on the test set. At specificity of 1.0 the sensitivity was 0.54, and the accuracy 0.81. CONCLUSION Combinations of EEG synchronization measures can contribute to early prognostication after CA. In particular, combining linear and non-linear measures is important for good predictive power. SIGNIFICANCE Quantitative methods might increase the prognostic yield of currently used multi-modal approaches.
Collapse
Affiliation(s)
- Frédéric Zubler
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
| | - Andreas Steimer
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Rebekka Kurmann
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Mojtaba Bandarabadi
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Jan Novy
- Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Heidemarie Gast
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Mauro Oddo
- Department of Intensive Care Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Kaspar Schindler
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Andrea O Rossetti
- Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| |
Collapse
|
15
|
|
16
|
Abstract
The problem of multiple surface clustering is a challenging task, particularly when the surfaces intersect. Available methods such as Isomap fail to capture the true shape of the surface near by the intersection and result in incorrect clustering. The Isomap algorithm uses shortest path between points. The main draw back of the shortest path algorithm is due to the lack of curvature constrained where causes to have a path between points on different surfaces. In this paper we tackle this problem by imposing a curvature constraint to the shortest path algorithm used in Isomap. The algorithm chooses several landmark nodes at random and then checks whether there is a curvature constrained path between each landmark node and every other node in the neighborhood graph. We build a binary feature vector for each point where each entry represents the connectivity of that point to a particular landmark. Then the binary feature vectors could be used as a input of conventional clustering algorithm such as hierarchical clustering. We apply our method to simulated and some real datasets and show, it performs comparably to the best methods such as K-manifold and spectral multi-manifold clustering.
Collapse
Affiliation(s)
- Amir Babaeian
- Department of Mathematics, University of California San Diego, San Diego, California, United States of America
| | - Alireza Bayestehtashk
- Department of Computer Science, Oregon Health and Science University, Portland, Oregon, United States of America
| | - Mojtaba Bandarabadi
- Department of Informatics Engineering, University of Coimbra, Coimbra, Portugal
| |
Collapse
|
17
|
Bandarabadi M, Rasekhi J, Teixeira CA, Netoff TI, Parhi KK, Dourado A. Early Seizure Detection Using Neuronal Potential Similarity: A Generalized Low-Complexity and Robust Measure. Int J Neural Syst 2015; 25:1550019. [DOI: 10.1142/s0129065715500197] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A novel approach using neuronal potential similarity (NPS) of two intracranial electroencephalogram (iEEG) electrodes placed over the foci is proposed for automated early seizure detection in patients with refractory partial epilepsy. The NPS measure is obtained from the spectral analysis of space-differential iEEG signals. Ratio between the NPS values obtained from two specific frequency bands is then investigated as a robust generalized measure, and reveals invaluable information about seizure initiation trends. A threshold-based classifier is subsequently applied on the proposed measure to generate alarms. The performance of the method was evaluated using cross-validation on a large clinical dataset, involving 183 seizure onsets in 1785 h of long-term continuous iEEG recordings of 11 patients. On average, the results show a high sensitivity of 86.9% (159 out of 183), a very low false detection rate of 1.4 per day, and a mean detection latency of 13.1 s from electrographic seizure onsets, while in average preceding clinical onsets by 6.3 s. These high performance results, specifically the short detection latency, coupled with the very low computational cost of the proposed method make it adequate for using in implantable closed-loop seizure suppression systems.
Collapse
Affiliation(s)
| | - Jalil Rasekhi
- Department of Electrical and Computer Engineering, Noshirvani University of Technology, Iran
| | - Cesar A. Teixeira
- Department of Informatics Engineering, University of Coimbra, Portugal
| | - Theoden I. Netoff
- Netoff Epilepsy Lab, Department of Biomedical Engineering, University of Minnesota, USA
| | - Keshab K. Parhi
- Department of Electrical and Computer Engineering, University of Minnesota, USA
| | - Antonio Dourado
- Department of Informatics Engineering, University of Coimbra, Portugal
| |
Collapse
|
18
|
Bandarabadi M, Rasekhi J, Teixeira CA, Karami MR, Dourado A. On the proper selection of preictal period for seizure prediction. Epilepsy Behav 2015; 46:158-66. [PMID: 25944112 DOI: 10.1016/j.yebeh.2015.03.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 02/16/2015] [Accepted: 03/10/2015] [Indexed: 12/12/2022]
Abstract
Supervised machine learning-based seizure prediction methods consider preictal period as an important prerequisite parameter during training. However, the exact length of the preictal state is unclear and varies from seizure to seizure. We propose a novel statistical approach for proper selection of the preictal period, which can also be considered either as a measure of predictability of a seizure or as the prediction capability of an understudy feature. The optimal preictal periods (OPPs) obtained from the training samples can be used for building a more accurate classifier model. The proposed method uses amplitude distribution histograms of features extracted from electroencephalogram (EEG) recordings. To evaluate this method, we extract spectral power features in different frequency bands from monopolar and space-differential EEG signals of 18 patients suffering from pharmacoresistant epilepsy. Furthermore, comparisons among monopolar channels with space-differential channels, as well as intracranial EEG (iEEG) and surface EEG (sEEG) signals, indicate that while monopolar signals perform better in iEEG recordings, no significant difference is noticeable in sEEG recordings.
Collapse
Affiliation(s)
- Mojtaba Bandarabadi
- CISUC/DEI, Center for Informatics and Systems of the University of Coimbra, Department of Informatics Engineering, Polo II, 3030-290 Coimbra, Portugal.
| | - Jalil Rasekhi
- Department of Biomedical Engineering, Faculty of Engineering, Babol Noshirvani University of Technology, Babol, Iran
| | - César A Teixeira
- CISUC/DEI, Center for Informatics and Systems of the University of Coimbra, Department of Informatics Engineering, Polo II, 3030-290 Coimbra, Portugal
| | - Mohammad R Karami
- Department of Biomedical Engineering, Faculty of Engineering, Babol Noshirvani University of Technology, Babol, Iran
| | - António Dourado
- CISUC/DEI, Center for Informatics and Systems of the University of Coimbra, Department of Informatics Engineering, Polo II, 3030-290 Coimbra, Portugal
| |
Collapse
|
19
|
Bandarabadi M, Teixeira CA, Rasekhi J, Dourado A. Epileptic seizure prediction using relative spectral power features. Clin Neurophysiol 2015; 126:237-48. [DOI: 10.1016/j.clinph.2014.05.022] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 04/14/2014] [Accepted: 05/10/2014] [Indexed: 10/25/2022]
|
20
|
Bandarabadi M, Teixeira CA, Netoff TI, Parhi KK, Dourado A. Robust and low complexity algorithms for seizure detection. Annu Int Conf IEEE Eng Med Biol Soc 2015; 2014:4447-50. [PMID: 25570979 DOI: 10.1109/embc.2014.6944611] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This paper presents two low complexity and yet robust methods for automated seizure detection using a set of 2 intracranial Electroencephalogram (iEEG) recordings. Most current seizure detection methods suffer from high number of false alarms, even when designed to be subject-specific. In this study, the ratios of power between pairs of frequency bands are used as features to detect epileptic seizures. For comparison, these features are calculated from monopolar and bipolar iEEG recordings. Optimal thresholds are individually determined and used for each feature. Alarms are generated when the measure passes the threshold. The detector was applied to long-term continuous invasive recordings from 5 patients with refractory partial epilepsy, containing 54 seizures in 780 hours. On average, the results revealed 88.9% sensitivity, a very low false detection rate of 0.041 per hour (h(-1)) and detection latency of 9.4 seconds.
Collapse
|
21
|
Rasekhi J, Mollaei MRK, Bandarabadi M, Teixeira CA, Dourado A. Epileptic Seizure Prediction based on Ratio and Differential Linear Univariate Features. J Med Signals Sens 2015; 5:1-11. [PMID: 25709936 PMCID: PMC4335140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 01/02/2015] [Indexed: 10/31/2022]
Abstract
Bivariate features, obtained from multichannel electroencephalogram recordings, quantify the relation between different brain regions. Studies based on bivariate features have shown optimistic results for tackling epileptic seizure prediction problem in patients suffering from refractory epilepsy. A new bivariate approach using univariate features is proposed here. Differences and ratios of 22 linear univariate features were calculated using pairwise combination of 6 electroencephalograms channels, to create 330 differential, and 330 relative features. The feature subsets were classified using support vector machines separately, as one of the two classes of preictal and nonpreictal. Furthermore, minimum Redundancy Maximum Relevance feature reduction method is employed to improve the predictions and reduce the number of false alarms. The studies were carried out on features obtained from 10 patients. For reduced subset of 30 features and using differential approach, the seizures were on average predicted in 60.9% of the cases (28 out of 46 in 737.9 h of test data), with a low false prediction rate of 0.11 h(-1). Results of bivariate approaches were compared with those achieved from original linear univariate features, extracted from 6 channels. The advantage of proposed bivariate features is the smaller number of false predictions in comparison to the original 22 univariate features. In addition, reduction in feature dimension could provide a less complex and the more cost-effective algorithm. Results indicate that applying machine learning methods on a multidimensional feature space resulting from relative/differential pairwise combination of 22 univariate features could predict seizure onsets with high performance.
Collapse
Affiliation(s)
- Jalil Rasekhi
- Department of Biomedical Engineering, Faculty of Engineering, Babol Noshirvani University of Technology, Babol, Iran,Address for correspondence: Jalil Rasekhi, Department of Biomedical Engineering, Faculty of Engineering, Babol Noshirvani University of Technology, Babol, Iran. E-mail:
| | - Mohammad Reza Karami Mollaei
- Department of Biomedical Engineering, Faculty of Engineering, Babol Noshirvani University of Technology, Babol, Iran
| | - Mojtaba Bandarabadi
- Department of Informatics Engineering, CISUC/DEI, Center for Informatics and Systems of the University of Coimbra, Polo II 3030-290, Coimbra, Portugal
| | - César A. Teixeira
- Department of Informatics Engineering, CISUC/DEI, Center for Informatics and Systems of the University of Coimbra, Polo II 3030-290, Coimbra, Portugal
| | - António Dourado
- Department of Informatics Engineering, CISUC/DEI, Center for Informatics and Systems of the University of Coimbra, Polo II 3030-290, Coimbra, Portugal
| |
Collapse
|
22
|
Rasekhi J, Mollaei MK, Bandarabadi M, Teixeira C, Dourado A. Epileptic seizure prediction based on ratio and differential linear univariate features. J Med Signals Sens 2015. [DOI: 10.4103/2228-7477.150371] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
23
|
Alexandre Teixeira C, Direito B, Bandarabadi M, Le Van Quyen M, Valderrama M, Schelter B, Schulze-Bonhage A, Navarro V, Sales F, Dourado A. Epileptic seizure predictors based on computational intelligence techniques: a comparative study with 278 patients. Comput Methods Programs Biomed 2014; 114:324-336. [PMID: 24657096 DOI: 10.1016/j.cmpb.2014.02.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 12/02/2013] [Accepted: 02/15/2014] [Indexed: 06/03/2023]
Abstract
The ability of computational intelligence methods to predict epileptic seizures is evaluated in long-term EEG recordings of 278 patients suffering from pharmaco-resistant partial epilepsy, also known as refractory epilepsy. This extensive study in seizure prediction considers the 278 patients from the European Epilepsy Database, collected in three epilepsy centres: Hôpital Pitié-là-Salpêtrière, Paris, France; Universitätsklinikum Freiburg, Germany; Centro Hospitalar e Universitário de Coimbra, Portugal. For a considerable number of patients it was possible to find a patient specific predictor with an acceptable performance, as for example predictors that anticipate at least half of the seizures with a rate of false alarms of no more than 1 in 6 h (0.15 h⁻¹). We observed that the epileptic focus localization, data sampling frequency, testing duration, number of seizures in testing, type of machine learning, and preictal time influence significantly the prediction performance. The results allow to face optimistically the feasibility of a patient specific prospective alarming system, based on machine learning techniques by considering the combination of several univariate (single-channel) electroencephalogram features. We envisage that this work will serve as benchmark data that will be of valuable importance for future studies based on the European Epilepsy Database.
Collapse
Affiliation(s)
| | - Bruno Direito
- Centre for Informatics and Systems, University of Coimbra, Portugal
| | | | - Michel Le Van Quyen
- Centre de Recherche de l'Institut du Cerveau et de la Moelle épinière (CRICM), Paris, France
| | - Mario Valderrama
- Centre de Recherche de l'Institut du Cerveau et de la Moelle épinière (CRICM), Paris, France
| | - Bjoern Schelter
- Freiburg Center for Data Analysis and Modeling, University of Freiburg, Freiburg, Germany
| | | | - Vincent Navarro
- Epilepsy Unit, Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - Francisco Sales
- Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - António Dourado
- Centre for Informatics and Systems, University of Coimbra, Portugal
| |
Collapse
|
24
|
Teixeira C, Direito B, Bandarabadi M, Dourado A. Output regularization of SVM seizure predictors: Kalman Filter versus the "Firing Power" method. Annu Int Conf IEEE Eng Med Biol Soc 2013; 2012:6530-3. [PMID: 23367425 DOI: 10.1109/embc.2012.6347490] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Two methods for output regularization of support vector machines (SVMs) classifiers were applied for seizure prediction in 10 patients with long-term annotated data. The output of the classifiers were regularized by two methods: one based on the Kalman Filter (KF) and other based on a measure called the "Firing Power" (FP). The FP is a quantification of the rate of the classification in the preictal class in a past time window. In order to enable the application of the KF, the classification problem was subdivided in a two two-class problem, and the real-valued output of SVMs was considered. The results point that the FP method raise less false alarms than the KF approach. However, the KF approach presents an higher sensitivity, but the high number of false alarms turns their applicability negligible in some situations.
Collapse
Affiliation(s)
- Cesar Teixeira
- Centre for Informatics and Systems, Polo II, University of Coimbra, 3030-290 Coimbra, Portugal.
| | | | | | | |
Collapse
|
25
|
Rasekhi J, Mollaei MRK, Bandarabadi M, Teixeira CA, Dourado A. Preprocessing effects of 22 linear univariate features on the performance of seizure prediction methods. J Neurosci Methods 2013; 217:9-16. [DOI: 10.1016/j.jneumeth.2013.03.019] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Revised: 03/23/2013] [Accepted: 03/25/2013] [Indexed: 11/25/2022]
|
26
|
Bandarabadi M, Dourado A, Teixeira CA, Netoff TI, Parhi KK. Seizure prediction with bipolar spectral power features using Adaboost and SVM classifiers. Annu Int Conf IEEE Eng Med Biol Soc 2013; 2013:6305-6308. [PMID: 24111182 DOI: 10.1109/embc.2013.6610995] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
This paper presents the results of our study on finding a lower complexity and yet a robust seizure prediction method using intracranial electroencephalogram (iEEG) recordings. We compare two classifiers: a low-complexity Adaboost and the more complex support vector machine (SVM). Adaboost is a linear classier using decision stumps, and SVM uses a nonlinear Gaussian kernel. Bipolar and/or time-differential spectral power features of different sub-bands are extracted from the iEEG signal. Adaboost is used to simultaneously classify as well as rank the features. Eliminating the low discriminating features reduces computational complexity and power consumption. The top features selected by Adaboost were also used as a feature set for SVM classification. The outputs of classifiers are regularized by applying a moving-average window and a threshold is used to generate alarms. The proposed methods were applied on 8 invasive recordings selected from the EPILEPSIAE database, the European database of EEG seizure recordings. Doublecross validation is used by separating data sets for training and optimization from testing. The key conclusion is that Adaboost performs slightly better than SVM using a reduced feature set on average with significantly less complexity resulting in a sensitivity of 77.1% (27 of 35 seizures in 873 h recordings) and a false alarm rate of 0.18 per hour.
Collapse
|
27
|
Bandarabadi M, Teixeira CA, Direito B, Dourado A. Epileptic seizure prediction based on a bivariate spectral power methodology. Annu Int Conf IEEE Eng Med Biol Soc 2012; 2012:5943-5946. [PMID: 23367282 DOI: 10.1109/embc.2012.6347347] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The spectral power of 5 frequently considered frequency bands (Alpha, Beta, Gamma, Theta and Delta) for 6 EEG channels is computed and then all the possible pairwise combinations among the 30 features set, are used to create a 435 dimensional feature space. Two new feature selection methods are introduced to choose the best candidate features among those and to reduce the dimensionality of this feature space. The selected features are then fed to Support Vector Machines (SVMs) that classify the cerebral state in preictal and non-preictal classes. The outputs of the SVM are regularized using a method that accounts for the classification dynamics of the preictal class, also known as "Firing Power" method. The results obtained using our feature selection approaches are compared with the ones obtained using minimum Redundancy Maximum Relevance (mRMR) feature selection method. The results in a group of 12 patients of the EPILEPSIAE database, containing 46 seizures and 787 hours multichannel recording for out-of-sample data, indicate the efficiency of the bivariate approach as well as the two new feature selection methods. The best results presented sensitivity of 76.09% (35 of 46 seizures predicted) and a false prediction rate of 0.15(-1).
Collapse
Affiliation(s)
- Mojtaba Bandarabadi
- Centre for Informatics and Systems (CISUC), University of Coimbra, Portugal.
| | | | | | | |
Collapse
|
28
|
Bandarabadi M, Teixeira CA, Sales F, Dourado A. Wepilet, optimal orthogonal wavelets for epileptic seizure prediction with one single surface channel. Annu Int Conf IEEE Eng Med Biol Soc 2011; 2011:7059-7062. [PMID: 22255964 DOI: 10.1109/iembs.2011.6091784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Wepilet is a series of novel orthogonal wavelets optimized for Electroencephalogram (EEG) signals, specialized for epileptic seizure prediction. The main idea is to design a mother wavelet that when applied to EEG signal to create the feature space, should enable a better classification of the brain state. Wepilet is developed by an iterative optimization process, employing Genetic Algorithm (GA). Frequency sub-band features are first extracted using wepilet under design for the EEG signal captured by one single surface channel. These features are then fed to Support Vector Machines (SVMs) that classify the cerebral state in preictal and inter-ictal classes. The results of the classification are then used to compute the Probability of Error Rate (PER), which in turn is the GA objective function to be minimized. Results in a group of four patients, indicate the efficiency of optimized mother wavelet compared to the well-known Daubechies wavelet in EEG processing.
Collapse
|