title: Electroencephalographic detection of respiratory-related cortical activity in humans: from event-related approaches to continuous connectivity evaluation.
abstract: The presence of a respiratory-related cortical activity during tidal breathing is abnormal and a hallmark of respiratory difficulties, but its detection requires superior discrimination and temporal resolution. The aim of this study was to validate a computational method using EEG covariance (or connectivity) matrices to detect a change in brain activity related to breathing. In 17 healthy subjects, EEG was recorded during resting unloaded breathing (RB), voluntary sniffs, and breathing against an inspiratory threshold load (ITL). EEG were analyzed by the specially developed covariance-based classifier, event-related potentials, and time-frequency (T-F) distributions. Nine subjects repeated the protocol. The classifier could accurately detect ITL and sniffs compared with the reference period of RB. For ITL, EEG-based detection was superior to airflow-based detection (P < 0.05). A coincident improvement in EEG-airflow correlation in ITL compared with RB (P < 0.05) confirmed that EEG detection relates to breathing. Premotor potential incidence was significantly higher before inspiration in sniffs and ITL compared with RB (P < 0.05), but T-F distributions revealed a significant difference between sniffs and RB only (P < 0.05). Intraclass correlation values ranged from poor (-0.2) to excellent (1.0). Thus, as for conventional event-related potential analysis, the covariance-based classifier can accurately predict a change in brain state related to a change in respiratory state, and given its capacity for near "real-time" detection, it is suitable to monitor the respiratory state in respiratory and critically ill patients in the development of a brain-ventilator interface.
authors: Neuroscience Research Australia and University of New South Wales, Sydney, Australia; a.hudson@neura.edu.au.
authors: Anna L
authors: AL
authors: Hudson
authors: Sorbonne Universités, Université Pierre et Marie Curie, University of Paris 06, Institut National de la Santé et de la Recherche Médicale, UMRS1158 Neurophysiologie Respiratoire Expérimentale et Clinique, Paris, France;
authors: Xavier
authors: X
authors: Navarro-Sune
authors: Centre National de la Recherche Scientifique UMR7225 at the Institut du Cerveau et de la Moelle Épinière, Paris, France;
authors: Jacques
authors: J
authors: Martinerie
authors: Centre National de la Recherche Scientifique UMR7225 at the Institut du Cerveau et de la Moelle Épinière, Paris, France;
authors: Pierre
authors: P
authors: Pouget
authors: Sorbonne Universités, Université Pierre et Marie Curie, University of Paris 06, Institut National de la Santé et de la Recherche Médicale, UMRS1158 Neurophysiologie Respiratoire Expérimentale et Clinique, Paris, France; Assistance Publique-Hopitaux de Paris (AP-HP), Groupe Hospitalier Pitie-Salpêtrière-Charles Foix, Département d'Anesthésie-Réanimation, Paris, France; and.
authors: Mathieu
authors: M
authors: Raux
authors: Centre National de la Recherche Scientifique UMR7225 at the Institut du Cerveau et de la Moelle Épinière, Paris, France;
authors: Mario
authors: M
authors: Chavez
authors: Sorbonne Universités, Université Pierre et Marie Curie, University of Paris 06, Institut National de la Santé et de la Recherche Médicale, UMRS1158 Neurophysiologie Respiratoire Expérimentale et Clinique, Paris, France; AP-HP, Groupe Hospitalier Pitie-Salpêtrière-Charles Foix, Service de Pneumologie et Réanimation Medicale, Paris, France.
authors: Thomas
authors: http://orcid.org/0000-0003-2868-9279
authors: T
authors: Similowski
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology*; D019054:Evoked Potentials, Motor; D005260:Female; D006801:Humans; D008297:Male; D011930:Reaction Time; D012119:Respiration
keywords: BCI; dyspnea; mechanical ventilation; voluntary movement