References of "Maquet, Pierre"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailAutomatic artifact detection for whole-night polysomnographic sleep recordings
Coppieters't Wallant, Dorothée ULg; Chellappa, Sarah Laxhmi ULg; Gaggioni, Giulia ULg et al

Poster (2014, September 17)

Detecting of bad channels and artifacts for whole-night polysomnographic recordings is very time consuming and tedious. We therefore developed an automatic procedure to automatize this job.

Detailed reference viewed: 47 (26 ULg)
Full Text
See detailHuman cortical excitability depends on time awake and circadian phase
Ly, Julien ULg; Chellappa, Sarah Laxhmi ULg; Gaggioni, Giulia ULg et al

Conference (2014, September 17)

At any point in time, human performance results from the interaction of two main factors: a circadian signal varying with the time of the day and the sleep need accrued throughout the preceding waking ... [more ▼]

At any point in time, human performance results from the interaction of two main factors: a circadian signal varying with the time of the day and the sleep need accrued throughout the preceding waking period. But what’s happen at the cortical cerebral level? We used a novel technique coupling transcranial magnetic stimulation with electroencephalography (TMS/EEG) to assess the influence of time spent awake and circadian phasis on human cortical excitability. Twenty-two healthy young men underwent 8 TMS/EEG sessions during a 28 hour sleep deprivation protocole. We found that cortical excitability depends on both time spent awake and circadian phasis. [less ▲]

Detailed reference viewed: 57 (14 ULg)
Full Text
Peer Reviewed
See detailHuman cortical excitability depends on time spent awake and circadian phase
Ly, Julien ULg; Chellappa, Sarah Laxhmi ULg; Gaggioni, Giulia ULg et al

Conference (2014, September 17)

At any point in time, human performance results from the interaction of two main factors: a circadian signal varying with the time of the day and the sleep need accrued throughout the preceding waking ... [more ▼]

At any point in time, human performance results from the interaction of two main factors: a circadian signal varying with the time of the day and the sleep need accrued throughout the preceding waking period. But what’s happen at the cortical cerebral level? We used a novel technique coupling transcranial magnetic stimulation with electroencephalography (TMS/EEG) to assess the influence of time spent awake and circadian phasis on human cortical excitability. Twenty-two healthy young men underwent 8 TMS/EEG sessions during a 28 hour sleep deprivation protocole. We found that cortical excitability depends on both time spent awake and circadian phasis. [less ▲]

Detailed reference viewed: 52 (13 ULg)
Full Text
Peer Reviewed
See detailDiagnosing multiple sclerosis with a gait measuring system, an analysis of the motor fatigue, and machine learning
Pierard, Sébastien ULg; Azrour, Samir ULg; Phan-Ba, Rémy et al

in Multiple Sclerosis Journal (2014, September 11), 20(S1), 171

Detailed reference viewed: 117 (35 ULg)
Full Text
Peer Reviewed
See detailAutomatic biorythms description from actigraphic data
González y Viagas, Miguel ULg; Ly, Julien ULg; Gaggioni, Giulia ULg et al

Poster (2014, September)

Detailed reference viewed: 28 (8 ULg)
Full Text
Peer Reviewed
See detailCortical excitability dynamics of during sleep deprivation set PVT performance
Borsu, Chloé; Gaggioni, Giulia ULg; Ly, Julien ULg et al

Poster (2014, September)

Detailed reference viewed: 24 (8 ULg)
Full Text
Peer Reviewed
See detailThe circadian system sets the temporal organization of basic human neuronal function
Chellappa, Sarah Laxhmi ULg; Ly, Julien; Gaggioni, Giulia ULg et al

Conference (2014, June 16)

Detailed reference viewed: 26 (7 ULg)
Full Text
Peer Reviewed
See detailMemory reactivation during rapid eye movement sleep promotes its generalization and integration in cortical stores.
Sterpenich, Virginie; Schmidt, Christina ULg; Albouy, Genevieve et al

in Sleep (2014), 37(6), 1061-751075-1075

STUDY OBJECTIVES: Memory reactivation appears to be a fundamental process in memory consolidation. In this study we tested the influence of memory reactivation during rapid eye movement (REM) sleep on ... [more ▼]

STUDY OBJECTIVES: Memory reactivation appears to be a fundamental process in memory consolidation. In this study we tested the influence of memory reactivation during rapid eye movement (REM) sleep on memory performance and brain responses at retrieval in healthy human participants. PARTICIPANTS: Fifty-six healthy subjects (28 women and 28 men, age [mean +/- standard deviation]: 21.6 +/- 2.2 y) participated in this functional magnetic resonance imaging (fMRI) study. METHODS AND RESULTS: Auditory cues were associated with pictures of faces during their encoding. These memory cues delivered during REM sleep enhanced subsequent accurate recollections but also false recognitions. These results suggest that reactivated memories interacted with semantically related representations, and induced new creative associations, which subsequently reduced the distinction between new and previously encoded exemplars. Cues had no effect if presented during stage 2 sleep, or if they were not associated with faces during encoding. Functional magnetic resonance imaging revealed that following exposure to conditioned cues during REM sleep, responses to faces during retrieval were enhanced both in a visual area and in a cortical region of multisensory (auditory-visual) convergence. CONCLUSIONS: These results show that reactivating memories during REM sleep enhances cortical responses during retrieval, suggesting the integration of recent memories within cortical circuits, favoring the generalization and schematization of the information. [less ▲]

Detailed reference viewed: 107 (10 ULg)
Full Text
Peer Reviewed
See detailNeuroimaging, cognition, light and circadian rhythms
Gaggioni, Giulia ULg; Maquet, Pierre ULg; Schmidt, Christina ULg et al

in Frontiers in Systems Neuroscience [=FNSYS] (2014)

Detailed reference viewed: 61 (20 ULg)
Full Text
Peer Reviewed
See detailLa Narcolepsie-Cataplexie aujourd'hui
DEPIERREUX, Frédérique ULg; FANIELLE, Julien ULg; Martin-Lecomte, Marianne ULg et al

in Revue Médicale de Liège (2014), 69(2), 72-81

Diagnostic criteria and pathophysiology of narcolepsy- <br />cataplexy have evolved considerably over the last 10 years. <br />The main cause, already mentioned in a previous paper, in the <br />Revue ... [more ▼]

Diagnostic criteria and pathophysiology of narcolepsy- <br />cataplexy have evolved considerably over the last 10 years. <br />The main cause, already mentioned in a previous paper, in the <br />Revue Médicale de Liège, in 2002, is based, in human beings, <br />on a destruction of specific cells located in the lateral and <br />posterior part of the hypothalamus (the perifornical nuclei, <br />containing some 70,000 neurons), producing peptides which <br />stimulate the central nervous system; they are called hypocretins <br />or orexins. The role of autoimmunity in their disappearance <br />becomes more evident. The treatment is simplified but <br />remains symptomatic. It is mainly based on Sodium Oxybate <br />or Gamma-Hydroxybutyrate, syrup, prescribed for the night. <br />The authors report on their own experience in this regard and <br />on future therapeutics more targeted towards the cause of the <br />disease. [less ▲]

Detailed reference viewed: 99 (25 ULg)
Peer Reviewed
See detailSleep loss changes executive brain responses in the wake maintenance zone
Jaspar, Mathieu ULg; Meyer, Christelle ULg; Muto, Vincenzo ULg et al

Conference (2014)

Objectives:Brain mechanisms underlying executive processes are regulated by circadian and sleep homeostatic processes. Furthermore, during sleep deprivation (SD), cognitive performance and neural ... [more ▼]

Objectives:Brain mechanisms underlying executive processes are regulated by circadian and sleep homeostatic processes. Furthermore, during sleep deprivation (SD), cognitive performance and neural responses are differentially modulated by a clock gene PERIOD3 polymorphism. Here, we investigated interindividual differences on executive brain responses under SD. Critically, we focused on the circadian evening wake maintenance zone (WMZ), a key time-point for sleep-wake regulation. Methods:Thirty healthy young volunteers, genotyped for the PER3 polymorphism (10 PER3 5/5;20 PER3 4/4 homozygotes), underwent42-h SD under constant routine conditions. They performed a 3-back working memorytask in 13successivefMRI sessions. To compare neural activity in the WMZ before and during SD, sessions were realigned according to individual dim light melatonin onset. Results:We tested for a group (PER3 5/5>PER3 4/4) by session effect (WMZ before vs. during SD). From the first evening WMZ(i.e. during a normal waking day) to the second (i.e. following 40h of continuous waking), PER3 5/5 individuals relative toPER3 4/4 showed significantly larger increase in responsesin the left mid-cingulate, bilateral precuneus and thalamus. Interestingly, these regions are involved in executive processes and arousal regulation (thalamus). Conclusions:These results show that the strong circadian wake-maintenance signal depends on sleep pressure, in a PER3-genotype dependent manner. Interestingly, pronounced genotype differences wereobserved in the thalamus, an area that compensates potential lower cortical activity under SD. [less ▲]

Detailed reference viewed: 70 (6 ULg)
Full Text
Peer Reviewed
See detailSleep loss changes executive brain responses in the wake maintenance zone
Jaspar, Mathieu ULg; Meyer, Christelle ULg; Muto, Vincenzo ULg et al

in Journal of Sleep Research (2014), 23(1), 61

Objectives: Brain mechanisms underlying executive processes are regulated by circadian and sleep homeostatic processes. Furthermore, during sleep deprivation (SD), cognitive performance and neural ... [more ▼]

Objectives: Brain mechanisms underlying executive processes are regulated by circadian and sleep homeostatic processes. Furthermore, during sleep deprivation (SD), cognitive performance and neural responses are differentially modulated by a clock gene PERIOD3 polymorphism. Here, we investigated interindividual differences on executive brain responses under SD. Critically, we focused on the circadian evening wake maintenance zone (WMZ), a key time-point for sleep-wake regulation. Methods: Thirty healthy young volunteers, genotyped for the PER3 polymorphism (10 PER3 5/5; 20 PER3 4/4 homozygotes), underwent 42-h SD under constant routine conditions. They performed a 3-back working memory task in 13 successive fMRI sessions. To compare neural activity in the WMZ before and during SD, sessions were realigned according to individual dim light melatonin onset. Results: We tested for a group (PER3 5/5 > PER3 4/4) by session effect (WMZ before vs. during SD). From the fi rst evening WMZ (i.e. during a normal waking day) to the second (i.e. following 40 h of continuous waking), PER3 5/5 individuals relative to PER3 4/4 showed significantly larger increase in responses in the left mid-cingulate, bilateral precuneus and thalamus. Interestingly, these regions are involved in executive processes and arousal regulation (thalamus). Conclusions: These results show that the strong circadian wake-maintenance signal depends on sleep pressure, in a PER3-genotype dependent manner. Interestingly, pronounced genotype differences were observed in the thalamus, an area that compensates potential lower cortical activity under SD. [less ▲]

Detailed reference viewed: 37 (10 ULg)
Peer Reviewed
See detailSeasonal variation in human executive brain responses
Meyer, Christelle ULg; Jaspar, Mathieu ULg; Muto, Vincenzo ULg et al

Poster (2014)

It is well established that cognition shows daily fluctuations with changes in circadian phase and sleep pressure. The physiological impact of season changes, which is well characterized in animals ... [more ▼]

It is well established that cognition shows daily fluctuations with changes in circadian phase and sleep pressure. The physiological impact of season changes, which is well characterized in animals, remains largely unexplored in human. Here we investigated the impact of seasonal variation on human cognitive brain function. This cross-sectional study,conducted in Liège (Belgium),spanned from May 2010 to October 2011. Following 8h in-lab baseline night of sleep, 30 volunteers (age 20.9+1.5; 15F)spent 42h awake under constant routine conditions(<5lux, semi-recumbent position, no time-cues). After12h recovery night, they underwent15minfMRI recording while performing a working memory 3-back task (3b) and a letter detection 0-back task (0b). Thus, fMRI data were acquired when volunteers had been in isolation under controlled conditionsfor 63h. Executive brain responses were isolated by subtracting 0b activity from 3b responses (3b>0b).Analysis tested seasonal influence on executive brain responses at the random effects level, using a phasoranalysis across the year.Inferences were conducted at p<0.05, after correction for multiple comparisons over a priori small volume of interest. Significanteffects of season on executive responses were detected inmiddle frontal and frontopolarregions, insula, and thalamus, with a maximum response at the end of summer and a minimum response at the end of winter.These brain areas are key regions for executive control and alertness. These results constitute the first demonstration that seasonality directly impacts on human cognitive brain functions. [less ▲]

Detailed reference viewed: 81 (9 ULg)
Full Text
Peer Reviewed
See detailCortical excitability dynamics of during sleep deprivation set PVT performance
Borsu, Chloé; Gaggioni, Giulia ULg; Ly, Julien et al

Conference (2014)

Detailed reference viewed: 17 (4 ULg)
Full Text
Peer Reviewed
See detailCortical excitability depends on time awake and circadian phase
Ly, Julien; Gaggioni, Giulia ULg; Chellappa, Sarah Laxhmi ULg et al

Conference (2014)

Detailed reference viewed: 23 (9 ULg)
Full Text
Peer Reviewed
See detailModulating effect of COMT genotype on the brain regions underlying proactive control process during inhibition
Jaspar, Mathieu ULg; Genon, Sarah ULg; Muto, Vincenzo ULg et al

in Cortex : A Journal Devoted to the Study of the Nervous System & Behavior (2014), 50

Introduction. Genetic variability related to the catechol-O-methyltransferase (COMT) gene (Val158Met polymorphism) has received increasing attention as a possible modulator of cognitive control functions ... [more ▼]

Introduction. Genetic variability related to the catechol-O-methyltransferase (COMT) gene (Val158Met polymorphism) has received increasing attention as a possible modulator of cognitive control functions. Methods. In an event-related fMRI study, a modified version of the Stroop task was administered to three groups of 15 young adults according to their COMT Val158Met genotype [Val/Val (VV), Val/Met (VM) and Met/Met (MM)]. Based on the theory of dual mechanisms of control (Braver, et al., 2007), the Stroop task has been built to induce proactive or reactive control processes according to the task context. Results. Behavioral results did not show any significant group differences for reaction times but Val allele carriers individuals are less accurate in the processing of incongruent items. fMRI results revealed that proactive control is specifically associated with increased activity in the anterior cingulate cortex (ACC) in carriers of the Met allele, while increased activity is observed in the middle frontal gyrus (MFG) in carriers of the Val allele. Conclusion. These observations, in keeping with a higher cortical dopamine level in MM individuals, support the hypothesis of a COMT Val158Met genotype modulation of the brain regions underlying proactive control, especially in frontal areas as suggested by Braver et al. [less ▲]

Detailed reference viewed: 95 (32 ULg)