Publications

Muto V. & Berthomier C., Looking for a balance between visual and automatic sleep scoring, NPJ Digit Med. 2023 Sep 5;6(1):165. doi: 10.1038/s41746-023-00915-7. PMID: 37670135; PMCID: PMC10480143.

> Access the complete article Looking for a balance between visual and automatic sleep scoring.

Deantoni M, Reyt M, Dourte M, de Haan S, Lesoinne A, Vandewalle G, Phillips C, Berthomier C, Maquet P, Muto V, Hammad G, Schmidt C, Baillet M. Circadian rapid eye movement sleep expression is associated with brain microstructural integrity in older adults. Commun Biol. 2024 Jun 22;7(1):758. doi: 10.1038/s42003-024-06415-y. PMID: 38909162; PMCID: PMC11193799.

> Abstract Circadian rapid eye movement sleep expression is associated with brain microstructural integrity in older adults

Billat, V.; Berthomier, C.; Clémençon, M.; Brandewinder, M.; Essid, S.; Damon, C.; Rigaud, F.; Bénichoux, A.; Maby, E.; Fornoni, L.; et al. Electroencephalography Response during an Incremental Test According to the V̇O2max Plateau Incidence. Appl. Sci. 2024, 14, 5411. https://doi.org/10.3390/app14135411

> Abstract Electroencephalography Response during an Incremental Test According to the V̇O2max Plateau Incidence

REM sleep quality is associated with balanced tonic activity of the locus coeruleus during wakefulness. N Mortazavi, P Talwar, E Koshmanova, R Sharifpour, E Beckers, A Berger, et al. bioRxiv, 2024.07. 12.603275

> Abstract REM sleep quality is associated with balanced tonic activity of the locus coeruleus during wakefulness

F Palacin, L Poinsard, J Mattei, C Berthomier, V Billat, Brain, Metabolic, and RPE Responses during a Free-Pace Marathon: A Preliminary Study, International Journal of Environmental Research and Public Health 21 (8), 1024

> Article Brain, Metabolic, and RPE Responses during a Free-Pace Marathon: A Preliminary Study

P Tankere, J Taillard, T Petitjean, C Berthomier, M Strauss, LP Derex, Somnolence diurne excessive et SAHOS traité: facteurs prédictifs des tests de maintien d’éveil, Médecine du Sommeil 21 (1), 22

> Abstract Somnolence diurne excessive et SAHOS traité: facteurs prédictifs des tests de maintien d’éveil

Sadoc M, Clairembault T, Coron E, Berthomier C, Le Dily S, Vavasseur F, Pavageau A, St Louis EK, Péréon Y, Neunlist M, Derkinderen P, Leclair-Visonneau L. Wake and non-rapid eye movement sleep dysfunction is associated with colonic neuropathology in Parkinson’s disease. Sleep. 2024 Mar 11;47(3):zsad310. doi: 10.1093/sleep/zsad310. PMID: 38156524.

> Complete article Wake and non-rapid eye movement sleep dysfunction is associated with colonic neuropathology in Parkinson’s disease.

Talwar P, Deantoni M, Van Egroo M, Muto V, Chylinski D, Koshmanova E, Jaspar M, Meyer C, Degueldre C, Berthomier C, Luxen A, Salmon E, Collette F, Dijk DJ, Schmidt C, Phillips C, Maquet P, Sherif S, Vandewalle G. Author Correction: In vivo marker of brainstem myelin is associated to quantitative sleep parameters in healthy young men. Sci Rep. 2024 Mar 13;14(1):6124. doi: 10.1038/s41598-024-56474-8. Erratum for: Sci Rep. 2023 Nov 27;13(1):20873. doi: 10.1038/s41598-023-47753-x. PMID: 38480866; PMCID: PMC10937964.

> Abstract Author Correction: In vivo marker of brainstem myelin is associated to quantitative sleep parameters in healthy young men

Talwar P, Deantoni M, Van Egroo M, Muto V, Chylinski D, Koshmanova E, Jaspar M, Meyer C, Degueldre C, Berthomier C, Luxen A, Salmon E, Collette F, Dijk DJ, Schmidt C, Phillips C, Maquet P, Sherif S, Vandewalle G. In vivo marker of brainstem myelin is associated to quantitative sleep parameters in healthy young men. Sci Rep. 2023 Nov 27;13(1):20873. doi: 10.1038/s41598-023-47753-x. Erratum in: Sci Rep. 2024 Mar 13;14(1):6124. doi: 10.1038/s41598-024-56474-8. PMID: 38012207; PMCID: PMC10682495.

> Abstract In vivo marker of brainstem myelin is associated to quantitative sleep parameters in healthy young men

Gobert F, Corneyllie A, Bastuji H, Berthomier C, Thevenet M, Abernot J, Raverot V, Dailler F, Guérin C, Gronfier C, Luauté J, Perrin F. Twenty-four-hour rhythmicities in disorders of consciousness are associated with a favourable outcome. Commun Biol. 2023 Nov 29;6(1):1213. doi: 10.1038/s42003-023-05588-2. PMID: 38030756; PMCID: PMC10687012.

> Texte complet Twenty-four-hour rhythmicities in disorders of consciousness are associated with a favourable outcome.

André C, Champetier P, Rehel S, Kuhn E, Touron E, Ourry V, Landeau B, Le Du G, Mézenge F, Segobin S, de la Sayette V, Vivien D, Chételat G, Rauchs G; Medit-Ageing Research Group. Rapid Eye Movement Sleep, Neurodegeneration, and Amyloid Deposition in Aging. Ann Neurol. 2023 May;93(5):979-990. doi: 10.1002/ana.26604. Epub 2023 Jan 27. PMID: 36641644.

> Full text Rapid Eye Movement Sleep, Neurodegeneration, and Amyloid Deposition in Aging.

> Access the complete article Sleep-dependent memory consolidation in breast cancer: Use of a virtual reality prospective memory task.

> Access the complete article Frontal grey matter microstructure is associated with sleep slow waves characteristics in late midlife. 

Chylinski D, Van Egroo M, Narbutas J, Muto V, Bahri MA, Berthomier C, Salmon E, Bastin C, Phillips C, Collette F, Maquet P, Carrier J, Lina JM, Vandewalle G. Timely coupling of sleep spindles and slow waves linked to early amyloid-β burden and predicts memory decline. Elife. 2022 May 31;11:e78191. doi: 10.7554/eLife.78191. PMID: 35638265..

> Access the complete article Timely coupling of sleep spindles and slow waves linked to early amyloid-β burden and predicts memory decline

Daphne O. Chylinski, Maxime Van Egroo, Justinas Narbutas, Martin Grignard, Ekaterina Koshmanova, Christian Berthomier, Pierre Berthomier, Marie Brandewinder, Eric Salmon, Mohamed Ali Bahri, Christine Bastin, Fabienne Collette, Christophe Phillips, Pierre Maquet, Vincenzo Muto, and Gilles Vandewalle. Heterogeneity in the links between sleep arousals, amyloid-β, and cognition. JCI Insight. 2021;6(24):e152858. https://doi.org/10.1172/jci.insight.152858.

> Access the complete article Heterogeneity in the links between sleep arousals, amyloid-β, and cognition

Jacques Taillard, Patricia Sagaspe, Christian Berthomier, Marie Brandewinder, Hélène Amieva, Jean-François Dartigues, Muriel Rainfray, Sandrine Harston, Jean-Arthur Micoulaud-Franchi and Pierre Philip, Non-REM Sleep Characteristics Predict Early Cognitive Impairment in an Aging Population, Front. Neurol., 13 March 2019 | https://doi.org/10.3389/fneur.2019.00197

Objective: Recent research suggests that sleep disorders or changes in sleep stages or EEG waveform precede over time the onset of the clinical signs of pathological cognitive impairment (e.g., Alzheimer’s disease). The aim of this study was to identify biomarkers based on EEG power values and spindle characteristics during sleep that occur in the early stages of mild cognitive impairment (MCI) in older adults.
Methods: This study was a case-control cross-sectional study with 1-year follow-up of cases. Patients with isolated subjective cognitive complaints (SCC) or MCI were recruited in the Bordeaux Memory Clinic (MEMENTO cohort). Cognitively normal controls were recruited. All participants were recorded with two successive polysomnography 1 year apart. Delta, theta, and sigma absolute spectral power and spindle characteristics (frequency, density, and amplitude) were analyzed from purified EEG during NREM and REM sleep periods during the entire second night.
Results: Twenty-nine patients (8 males, age = 71 ± 7 years) and 29 controls were recruited at T0. Logistic regression analyses demonstrated that age-related cognitive impairment were associated with a reduced delta power (odds ratio (OR) 0.072, P < 0.05), theta power (OR 0.018, P < 0.01), sigma power (OR 0.033, P < 0.05), and spindle maximal amplitude (OR 0.002, P < 0.05) during NREM sleep. Variables were adjusted on age, gender, body mass index, educational level, and medication use. Seventeen patients were evaluated at 1-year follow-up. Correlations showed that changes in self-reported sleep complaints, sleep consolidation, and spindle characteristics (spectral power, maximal amplitude, duration, and frequency) were associated with cognitive impairment (P < 0.05).
Conclusion: A reduction in slow-wave, theta and sigma activities, and a modification in spindle characteristics during NREM sleep are associated very early with a greater risk of the occurrence of cognitive impairment. Poor sleep consolidation, lower amplitude, and faster frequency of spindles may be early sleep biomarkers of worsening cognitive decline in older adults.

> Full text: Non-REM Sleep Characteristics Predict Early Cognitive Impairment in an Aging Population

Maire M, Reichert CF, Gabel V, Viola AU, Phillips C, Berthomier C, Borgwardt S, Cajochen C, Schmidt C. Human brain patterns underlying vigilant attention: impact of sleep debt, circadian phase and attentional engagement. Sci Rep. 2018 Jan 17;8(1):970. doi: 10.1038/s41598-017-17022-9. Sleepiness and cognitive function vary over the 24-h day due to circadian and sleep-wake-dependent mechanisms. However, the underlying cerebral hallmarks associated with these variations remain to be fully established. Using functional magnetic resonance imaging (fMRI), we investigated brain responses associated with circadian and homeostatic sleep-wake-driven dynamics of subjective sleepiness throughout day and night. Healthy volunteers regularly performed a psychomotor vigilance task (PVT) in the MR-scanner during a 40-h sleep deprivation (high sleep pressure) and a 40-h multiple nap protocol (low sleep pressure). When sleep deprived, arousal-promoting thalamic activation during optimal PVT performance paralleled the time course of subjective sleepiness with peaks at night and troughs on the subsequent day. Conversely, task-related cortical activation decreased when sleepiness increased as a consequence of higher sleep debt. Under low sleep pressure, we did not observe any significant temporal association between PVT-related brain activation and subjective sleepiness. Thus, a circadian modulation in brain correlates of vigilant attention was only detectable under high sleep pressure conditions. Our data indicate that circadian and sleep homeostatic processes impact on vigilant attention via specific mechanisms; mirrored in a decline of cortical resources under high sleep pressure, opposed by a subcortical « rescuing » at adverse circadian times. > Full text: Human brain patterns underlying vigilant attention: impact of sleep debt, circadian phase and attentional engagement

Dang-Vu TT, Hatch B, Salimi A, Mograss M, Boucetta S, O’Byrne J, Brandewinder M, Berthomier C, Gouin JP., Sleep spindles may predict response to cognitive behavioral therapy for chronic insomnia, Sleep Med. 2017 Nov;39:54-61. doi: 10.1016/j.sleep.2017.08.012. BACKGROUND: While cognitive-behavioral therapy for insomnia constitutes the first-line treatment for chronic insomnia, only few reports have investigated how sleep architecture relates to response to this treatment. In this pilot study, we aimed to determine whether pre-treatment sleep spindle density predicts treatment response to cognitive-behavioral therapy for insomnia. METHODS: Twenty-four participants with chronic primary insomnia participated in a 6-week cognitive-behavioral therapy for insomnia performed in groups of 4-6 participants. Treatment response was assessed using the Pittsburgh Sleep Quality Index and the Insomnia Severity Index measured at pre- and post-treatment, and at 3- and 12-months’ follow-up assessments. Secondary outcome measures were extracted from sleep diaries over 7 days and overnight polysomnography, obtained at pre- and post-treatment. Spindle density during stage N2-N3 sleep was extracted from polysomnography at pre-treatment. Hierarchical linear modeling analysis assessed whether sleep spindle density predicted response to cognitive-behavioral therapy. RESULTS: After adjusting for age, sex, and education level, lower spindle density at pre-treatment predicted poorer response over the 12-month follow-up, as reflected by a smaller reduction in Pittsburgh Sleep Quality Index over time. Reduced spindle density also predicted lower improvements in sleep diary sleep efficiency and wake after sleep onset immediately after treatment. There were no significant associations between spindle density and changes in the Insomnia Severity Index or polysomnography variables over time. CONCLUSION: These preliminary results suggest that inter-individual differences in sleep spindle density in insomnia may represent an endogenous biomarker predicting responsiveness to cognitive-behavioral therapy. Insomnia with altered spindle activity might constitute an insomnia subtype characterized by a neurophysiological vulnerability to sleep disruption associated with impaired responsiveness to cognitive-behavioral therapy. > Abstract: Sleep spindles may predict response to cognitive-behavioral therapy for chronic insomnia.

Reichert CF, Maire M, Gabel V, Viola AU, Götz T, Scheffler K, Klarhöfer M, Berthomier C, Strobel W, Phillips C, Salmon E, Cajochen C, Schmidt C., Cognitive brain responses during circadian wake-promotion: evidence for sleep-pressure-dependent hypothalamic activations, Sci Rep. 2017 Jul 17;7(1):5620. doi: 10.1038/s41598-017-05695-1. The two-process model of sleep-wake regulation posits that sleep-wake-dependent homeostatic processes interact with the circadian timing system to affect human behavior. The circadian timing system is fundamental to maintaining stable cognitive performance, as it counteracts growing homeostatic sleep pressure during daytime. Using magnetic resonance imaging, we explored brain responses underlying working memory performance during the time of maximal circadian wake-promotion under varying sleep pressure conditions. Circadian wake-promoting strength was derived from the ability to sleep during an evening nap. Hypothalamic BOLD activity was positively linked to circadian wake-promoting strength under normal, but not under disproportionally high or low sleep pressure levels. Furthermore, higher hypothalamic activity under normal sleep pressure levels predicted better performance under sleep loss. Our results reappraise the two-process model by revealing a homeostatic-dose-dependent association between circadian wake-promotion and cognition-related hypothalamic activity. > Full text: Cognitive brain responses during circadian wake-promotion: evidence for sleep-pressure-dependent hypothalamic activations

Vallat R, Lajnef T, Eichenlaub JB, Berthomier C, Jerbi K, Morlet D, Ruby PM., Increased Evoked Potentials to Arousing Auditory Stimuli during Sleep: Implication for the Understanding of Dream Recall. Front Hum Neurosci. 2017 Mar 21;11:132. doi: 10.3389/fnhum.2017.00132. eCollection 2017. High dream recallers (HR) show a larger brain reactivity to auditory stimuli during wakefulness and sleep as compared to low dream recallers (LR) and also more intra-sleep wakefulness (ISW), but no other modification of the sleep macrostructure. To further understand the possible causal link between brain responses, ISW and dream recall, we investigated the sleep microstructure of HR and LR, and tested whether the amplitude of auditory evoked potentials (AEPs) was predictive of arousing reactions during sleep. Participants (18 HR, 18 LR) were presented with sounds during a whole night of sleep in the lab and polysomnographic data were recorded. Sleep microstructure (arousals, rapid eye movements (REMs), muscle twitches (MTs), spindles, KCs) was assessed using visual, semi-automatic and automatic validated methods. AEPs to arousing (awakenings or arousals) and non-arousing stimuli were subsequently computed. No between-group difference in the microstructure of sleep was found. In N2 sleep, auditory arousing stimuli elicited a larger parieto-occipital positivity and an increased late frontal negativity as compared to non-arousing stimuli. As compared to LR, HR showed more arousing stimuli and more long awakenings, regardless of the sleep stage but did not show more numerous or longer arousals. These results suggest that the amplitude of the brain response to stimuli during sleep determine subsequent awakening and that awakening duration (and not arousal) is the critical parameter for dream recall. Notably, our results led us to propose that the minimum necessary duration of an awakening during sleep for a successful encoding of dreams into long-term memory is approximately 2 min. > Full text: Increased Evoked Potentials to Arousing Auditory Stimuli during Sleep: Implication for the Understanding of Dream

Dang-Vu T. T., Salimi A., Boucetta S., Wenzel K., O’Byrne J., M. Brandewinder M., Berthomier C. and Gouin J.-P.. Sleep spindles predict stress-related increases in sleep disturbances. Front. Hum. Neurosci., 10 February 2015 | doi: 10.3389/fnhum.2015.00068 The aim of this study was to prospectively assess whether spindle density would predict the worsening of sleep disturbances in response to a standardized stressor. We chose to follow a population of undergraduate university students during a period of increasing academic stress. In this context, assessing students at the beginning of the semester, corresponding to a lower stress period, and reevaluating them during a follow-up in the week preceding the final examinations, a period of higher stress, provides a unique opportunity to examine individual differences in the evolution of insomnia symptoms in response to a standardized stressor. > Full text: Sleep spindles predict stress-related increases in sleep disturbances

Ruby P, Blochet C, Eichenlaub J-B, Bertrand O, Morlet D, Bidet-Caulet A. Alpha Reactivity to Complex Sounds Differs during REM Sleep and Wakefulness. PLoS ONE 8(11): e79989, 2013.

We aimed at better understanding the brain mechanisms involved in the processing of alerting meaningful sounds during sleep, investigating alpha activity. During EEG acquisition, subjects were presented with a passive auditory oddball paradigm including rare complex sounds called Novels (the own first name – OWN, and an unfamiliar first name – OTHER) while they were watching a silent movie in the evening or sleeping at night. During the experimental night, the subjects’ quality of sleep was generally preserved. During wakefulness, the decrease in alpha power (8–12 Hz) induced by Novels was significantly larger for OWN than for OTHER at parietal electrodes, between 600 and 900 ms after stimulus onset. Conversely, during REM sleep, Novels induced an increase in alpha power (from 0 to 1200 ms at all electrodes), significantly larger for OWN than for OTHER at several parietal electrodes between 700 and 1200 ms after stimulus onset. These results show that complex sounds have a different effect on the alpha power during wakefulness (decrease) and during REM sleep (increase) and that OWN induce a specific effect in these two states. The increased alpha power induced by Novels during REM sleep may 1) correspond to a short and transient increase in arousal; in this case, our study provides an objective measure of the greater arousing power of OWN over OTHER, 2) indicate a cortical inhibition associated with sleep protection. These results suggest that alpha modulation could participate in the selection of stimuli to be further processed during sleep.

> Full text Alpha Reactivity to Complex Sounds Differs during REM Sleep and Wakefulness

Ruby P, Blochet C, Eichenlaub JB, Bertrand O, Morlet D, Bidet-Caulet A. Alpha reactivity to first names differs in subjects with high and low dream recall frequency. Front Psychol.;4:419, 2013.

Studies in cognitive psychology showed that personality (openness to experience, thin boundaries, absorption), creativity, nocturnal awakenings, and attitude toward dreams are significantly related to dream recall frequency (DRF). These results suggest the possibility of neurophysiological trait differences between subjects with high and low DRF. To test this hypothesis we compared sleep characteristics and alpha reactivity to sounds in subjects with high and low DRF using polysomnographic recordings and electroencephalography (EEG). We acquired EEG from 21 channels in 36 healthy subjects while they were presented with a passive auditory oddball paradigm (frequent standard tones, rare deviant tones and very rare first names) during wakefulness and sleep (intensity, 50 dB above the subject’s hearing level). Subjects were selected as High-recallers (HR, DRF = 4.42 ± 0.25 SEM, dream recalls per week) and Low-recallers (LR, DRF = 0.25 ± 0.02) using a questionnaire and an interview on sleep and dream habits. Despite the disturbing setup, the subjects’ quality of sleep was generally preserved. First names induced a more sustained decrease in alpha activity in HR than in LR at Pz (1000–1200 ms) during wakefulness, but no group difference was found in REM sleep. The current dominant hypothesis proposes that alpha rhythms would be involved in the active inhibition of the brain regions not involved in the ongoing brain operation. According to this hypothesis, a more sustained alpha decrease in HR would reflect a longer release of inhibition, suggesting a deeper processing of complex sounds than in LR during wakefulness. A possibility to explain the absence of group difference during sleep is that increase in alpha power in HR may have resulted in awakenings. Our results support this hypothesis since HR experienced more intra sleep wakefulness than LR (30 ± 4 vs. 14 ± 4 min). As a whole our results support the hypothesis of neurophysiological trait differences in high and low-recallers.

> Full text: Alpha reactivity to first names differs in subjects with high and low dream recall frequency

Schmidt C, Peigneux P, Leclercq Y, Sterpenich V, Vandewalle G, Philips C, Berthomier P, Berthomier C, Tinguely G, Gais S, Schabus M, Desseilles M, Dang-Vu T, Salmon E, Degueldre C, Balteau E, Luxen A, Cajochen C, Maquet P, Collette F. Circadian preference modulates the neural substrate of conflict processing across the day. PLoS One. 2012;7(1):e29658. 2012 Jan 4. PLoS One. 2012;7(1):e29658. 2012 Jan 4.

Human morning and evening chronotypes differ in their preferred timing for sleep and wakefulness, as well as in optimal daytime periods to cope with cognitive challenges. Recent evidence suggests that these preferences are not a simple by-product of socio-professional timing constraints, but can be driven by inter-individual differences in the expression of circadian and homeostatic sleep-wake promoting signals. Chronotypes thus constitute a unique tool to access the interplay between those processes under normally entrained day-night conditions, and to investigate how they impinge onto higher cognitive control processes. Using functional magnetic resonance imaging (fMRI), we assessed the influence of chronotype and time-of-day on conflict processing-related cerebral activity throughout a normal waking day. Sixteen morning and 15 evening types were recorded at two individually adapted time points (1.5 versus 10.5 hours spent awake) while performing the Stroop paradigm. Results show that interference-related hemodynamic responses are maintained or even increased in evening types from the subjective morning to the subjective evening in a set of brain areas playing a pivotal role in successful inhibitory functioning, whereas they decreased in morning types under the same conditions. Furthermore, during the evening hours, activity in a posterior hypothalamic region putatively involved in sleep-wake regulation correlated in a chronotype-specific manner with slow wave activity at the beginning of the night, an index of accumulated homeostatic sleep pressure. These results shed light into the cerebral mechanisms underlying inter-individual differences of higher-order cognitive state maintenance under normally entrained day-night conditions.

> Full text: Circadian preference modulates the neural substrate of conflict processing across the day

Schmidt C, Collette F, Leclercq Y, Sterpenich V, Vandewalle G, Berthomier P, Berthomier C, Philipps C, Tinguely G, Darsaud A, Gais S, Schabus M, Desseilles M, Dang-Vu T, Salmon E, Balteau E, Degueldre C, Luxen A, Maquet P, Cajochen C, Peigneux P, Homeostatic sleep pressure and responses to sustained attention in the suprachiasmatic area, Science, 324 (5926):516-9, 2009.

Throughout the day, cognitive performance is under the combined influence of circadian processes and homeostatic sleep pressure. Some people perform best in the morning, whereas others are more alert in the evening. These chronotypes provide a unique way to study the effects of sleep-wake regulation on the cerebral mechanisms supporting cognition. Using functional magnetic resonance imaging in extreme chronotypes, we found that maintaining attention in the evening was associated with higher activity in evening than morning chronotypes in a region of the locus coeruleus and in a suprachiasmatic area (SCA) including the circadian master clock. Activity in the SCA decreased with increasing homeostatic sleep pressure. This result shows the direct influence of the homeostatic and circadian interaction on the neural activity underpinning human behavior.

> Abstract: Homeostatic sleep pressure and responses to sustained attention in the suprachiasmatic area

Variability of sleep stage scoring in late midlife and early old age, Chylinski D., Berthomier C., Lambot E., Frenette S., Brandewinder M., Carrier J., Vandewalle G. & Muto V. J Sleep Res. 2021 Jun 24:e13424. doi: 10.1111/jsr.13424. Epub ahead of print. PMID: 34169604.

Study objectives: To assess the performance of the single-channel automatic sleep staging (AS) software ASEEGA in adult patients diagnosed with various sleep disorders.

Methods: Sleep recordings were included of 95 patients (38 women, 40.5 ± 13.7 years) diagnosed with insomnia (n = 23), idiopathic hypersomnia (n = 24), narcolepsy (n = 24), and obstructive sleep apnea (n = 24). Visual staging (VS) was performed by two experts (VS1 and VS2) according to the American Academy of Sleep Medicine rules. AS was based on the analysis of a single electroencephalogram channel (Cz-Pz), without any information from electro-oculography nor electromyography. The epoch-by-epoch agreement (concordance and Conger’s coefficient [κ]) was compared pairwise (VS1-VS2, AS-VS1, AS-VS2) and between AS and consensual VS. Sleep parameters were also compared.

Results: The pairwise agreements were: between AS and VS1, 78.6% (κ = 0.70); AS and VS2, 75.0% (0.65); and VS1 and VS2, 79.5% (0.72). Agreement between AS and consensual VS was 85.6% (0.80), with the following distribution: insomnia 85.5% (0.80), narcolepsy 83.8% (0.78), idiopathic hypersomnia 86.1% (0.68), and obstructive sleep disorder 87.2% (0.82). A significant low-amplitude scorer effect was observed for most sleep parameters, not always driven by the same scorer. Hypnograms obtained with AS and VS exhibited very close sleep organization, except for 80% of rapid eye movement sleep onset in the group diagnosed with narcolepsy missed by AS.

Conclusions: Agreement between AS and VS in sleep disorders is comparable to that reported in healthy individuals and to interexpert agreement in patients. ASEEGA could therefore be considered as a complementary sleep stage scoring tool in clinical practice, after improvement of rapid eye movement sleep onset detection.

> Access Variability of sleep stage scoring in late midlife and early old age

Automatic analysis of single-channel sleep EEG in a large spectrum of sleep disorders. Journal of Clinical Sleep Medicine 2021; 17 (3), 393-402, Peter-Derex L, Berthomier C, Taillard J, Berthomier P, Bouet R, Mattout J, Brandewinder M, Bastuji H. 

Berthomier C; Drouot X; Herman-Stoïca M; Berthomier P; Prado J; Bokar-Thire D; Benoit O; Mattout J; d’Ortho MP., Automatic Analysis of Single-Channel Sleep EEG: Validation in Healthy Individuals, Sleep 2007;30(11):1587-1595.

STUDY OBJECTIVE: To assess the performance of automatic sleep scoring software (ASEEGA) based on a single EEG channel comparatively with manual scoring (2 experts) of conventional full polysomnograms.

DESIGN: Polysomnograms from 15 healthy individuals were scored by 2 independent experts using conventional R&K rules. The results were compared to those of ASEEGA scoring on an epoch-by-epoch basis.

SETTING: Sleep laboratory in the physiology department of a teaching hospital.

PARTICIPANTS: Fifteen healthy volunteers.

MEASUREMENTS AND RESULTS: The epoch-by-epoch comparison was based on classifying into 2 states (wake/sleep), 3 states (wake/REM/ NREM), 4 states (wake/REM/stages 1-2/SWS), or 5 states (wake/REM/ stage 1/stage 2/SWS). The obtained overall agreements, as quantified by the kappa coefficient, were 0.82, 0.81, 0.75, and 0.72, respectively. Furthermore, obtained agreements between ASEEGA and the expert consensual scoring were 96.0%, 92.1%, 84.9%, and 82.9%, respectively. Finally, when classifying into 5 states, the sensitivity and positive predictive value of ASEEGA regarding wakefulness were 82.5% and 89.7%, respectively. Similarly, sensitivity and positive predictive value regarding REM state were 83.0% and 89.1%.

CONCLUSIONS: Our results establish the face validity and convergent validity of ASEEGA for single-channel sleep analysis in healthy individuals. ASEEGA appears as a good candidate for diagnostic aid and automatic ambulant scoring.

> Full text: Automatic Analysis of Single-Channel Sleep EEG: Validation in Healthy Individuals

P. J. Escourrou, M. Brandewinder, C. Berthomier, P. Berthomier, G. Baffet, Z. Balekji, N. Puisais, G. Roisman, Respiratory events during stable wake in sleep apnea patients: occurrence and mechanism., European Respiratory Journal 2018 52: PA2509; DOI: 10.1183/13993003.congress-2018.PA2509

O’Byrne J, Boucetta S, Reed L,Malhi O, Zhang V, Arcelin A, Wenzel K, Brandewinder M, Berthomier C, Gouin J-P, Dang-Vu TT. Spindles and slow waves predict treatment responses to cognitive-behavioural therapy for chronic primary insomnia. J. Sleep Res., 23 Suppl. 1:209, 2014

22nd ESRS Congress, Tallinn, Estonia
16 – 20 September 2014

Sagaspe P, Taillard J, Chaufton C, Berthomier C, Brandewinder M, Amiéva H, Dartigues J-F, Philip P. Polysomnographic data in patients with isolated memory complaints or mild cognitive impairment. J. Sleep Res., 23 Suppl. 1:240, 2014

22nd ESRS Congress, Tallinn, Estonia
16 – 20 September 2014

Van Beers, P., Berthomier, C., Prado, J., Berthomier, P., & Coste, O., HRV Analysis during Sleep: Clinical Interest of a New Automatic Sleep Analysis, SLEEP Vol. 32, pp. A374-A374, 2009.

23rd Annual Meeting of the Associated Professional Sleep Societies (SLEEP 2009)
June 06-11, 2009, Seattle, Washington, USA

Berthomier C, Drouot X, Herman-Stoïca M, Berthomier P, Prado J, Benoit O, Mattout J, d’Ortho MP, Wake-REM-NREM Automatic Classification based on a Single EEG Channel: Epoch by Epoch Comparison with Human Sleep Scoring in Patients, J. Sleep Res., Vol 15/suppl.1, P295, 2006

18th Congress of the European Sleep Research Society (ESRS)
September 12-16, 2006, Innsbruck, Austria

Berthomier C, Drouot X, Herman-Stoïca M, Berthomier P, Prado J, Mattout J, d’Ortho MP, A Wake-REM-NREM Automatic Analysis Using a Single EEG Channel: Epoch by Epoch Comparison with Human Sleep Scoring in Healthy Subjects, Sleep Medicine, Vol. 6/Suppl.2 (2005), S194

First Congress of the World Association of Sleep Medicine (WASM)
15-18 October 2005, Berlin, Germany