Jacques Montplaisir

Université de Montréal | UdeM · Department of Psychiatry

Isolated rapid eye movement sleep behaviour disorder (iRBD) is a sleep disorder characterized by the loss of rapid eye movement sleep muscle atonia and the appearance of abnormal movements and vocalizations during rapid eye movement sleep. It is a strong marker of incipient synucleinopathy such as dementia with Lewy bodies and Parkinson’s disease....

The basal forebrain cholinergic system (BFCS) degenerates in Alzheimer’s disease (AD) before the onset of dementia. Interestingly, rapid‐eye movement (REM) sleep is highly dependent on cholinergic activity. In AD patients, REM sleep duration is reduced but the underlying brain mechanisms are still unclear. Our objective was to investigate the assoc...

Neuroimaging studies in obstructive sleep apnea (OSA) have found both gray matter atrophy and hypertrophy in medial temporal lobe subregions, the latter probably reflecting edema. Whether and how these changes progress over time when OSA is treated or untreated remains unclear. Here, we investigated gray matter volume changes in medial temporal lob...

Isolated rapid eye movement sleep behavior disorder (iRBD) is a prodromal synucleinopathy characterized by several changes including brain atrophy. The mechanisms underlying atrophy in iRBD are poorly understood. Here, we performed imaging transcriptomics and comprehensive spatial mapping in a multicentric cohort of 171 polysomnography-confirmed iR...

Importance: Understanding the longitudinal, bidirectional associations between disturbed sleep and depression in childhood and adolescence is crucial for the development of prevention and intervention programs. Objective: To test for bidirectional associations and cascade processes between disturbed sleep and depressive symptoms covering both ch...

Isolated REM sleep behaviour disorder (iRBD) is a synucleinopathy characterized by abnormal behaviours and vocalizations during REM sleep. Most iRBD patients develop dementia with Lewy bodies, Parkinson’s disease, or multiple system atrophy over time. Patients with iRBD exhibit brain atrophy patterns that are reminiscent of those observed in overt...

Isolated REM sleep behaviour disorder (iRBD) is a synucleinopathy characterized by abnormal behaviours and vocalizations during REM sleep. Most iRBD patients develop dementia with Lewy bodies, Parkinson's disease, or multiple system atrophy over time. Patients with iRBD exhibit brain atrophy patterns that are reminiscent of those observed in overt...

Sleepwalking is a common non-rapid eye movement (NREM) parasomnia and a significant cause of sleep-related injuries. While evidence suggest that the occurrence of this condition is partly determined by genetic factors, its pattern of inheritance remains unclear, and few molecular studies have been conducted. One promising candidate is the adenosine...

Several studies have confirmed the α-synuclein real-time quaking-induced conversion (RT-QuIC) assay to have high sensitivity and specificity for Parkinson’s disease. However, whether the assay can be used as a robust, quantitative measure to monitor disease progression, stratify different synucleinopathies and predict disease conversion in patients...

Background Far from being benign, somnambulistic episodes can be frequent and/or severe and potentially injurious. Episodes may also be accompanied by sleep mentation with variable degrees of retrograde amnesia. The present study investigated how somnambulistic episodes unfold from childhood through adulthood, a topic that remains understudied. Me...

Recent studies have suggested that obstructive sleep apnea (OSA) could be a modifiable risk factor for dementia. Consequently, efforts have been made to better understand the role of OSA on brain structure integrity, but results between studies are inconsistent. Discrepancies could be partly due to moderating factors (e.g., sex) or complex physiolo...

Our research team has demonstrated that quantitative electroencephalography (qEEG) slowing during rapid‐eye movement (REM) sleep is a more powerful tool to discriminate patients with mild cognitive impairment (MCI) or Alzheimer Disease (AD) from healthy controls than waking EEG. Cortical activation during REM sleep highly depends on the cholinergic...

Background: Rapid-eye-movement sleep behavior disorder (RBD) is a major risk factor for Parkinson's disease and dementia with Lewy bodies. More than a third of RBD patients have mild cognitive impairment (MCI), but their specific structural brain alterations remain poorly understood. Objective: This study aimed to investigate the local deformati...

Background Idiopathic rapid eye movement sleep behavior disorder (iRBD) is a major risk factor for synucleinopathies, and patients often present with clinical signs and morphological brain changes. However, there is an important heterogeneity in the presentation and progression of these alterations, and the brain regions that are more vulnerable to...

REM sleep behavior disorder (RBD) represents both an early marker and key symptom of synucleinopathies, mainly Parkinson disease (PD) and Lewy body dementia (LBD), and a strong opportunity for early clinical intervention for these conditions. Yet, the genetics of RBD are currently not well characterized. In this study, we perform the first genome-w...

Sleepwalking has been conceptualized as deregulation between slow-wave sleep and arousal, with its occurrence in predisposed patients increasing following sleep deprivation. Recent evidence showed autonomic changes before arousals and somnambulistic episodes, suggesting that autonomic dysfunctions may contribute to the pathophysiology of sleepwalki...

Introduction: Several studies have investigated the first-night effect in normal subjects of different age groups. The aim of the study was to measure the first-night effect in a clinical population of patients with severe insomnia and to assess the contribution of various factors including depression and anxiety scores. Methods: 31 patients with p...

Obstructive sleep apnea (OSA) is associated with abnormal cerebral perfusion at wakefulness, but whether these anomalies evolve over time is unknown. Here, we examined longitudinal changes in regional cerebral blood flow (rCBF) distribution in late middle‐aged and older adults with treated or untreated OSA. Twelve controls (64.8 ± 8.0 years) and 23...

Objective This multi‐language study employed simple speech recording and high‐end pattern analysis to provide sensitive and reliable non‐invasive biomarkers of prodromal vs. manifest alpha‐synucleinopathy in patients with idiopathic rapid eye movement sleep behaviour disorder (iRBD) and early‐stage Parkinson's disease (PD). Methods We performed a...

Nightmares are highly dysphoric dreams that are well-remembered upon awakening. Frequent nightmares have been associated with psychopathology and emotional dysregulation, yet their neural mechanisms remain largely unknown. Our neurocognitive model posits that nightmares reflect dysfunction in a limbic-prefrontal circuit comprising medial prefrontal...

Objective: To examine the role of genes identified through genome-wide association studies (GWASs) of Parkinson disease (PD) in the risk of isolated rapid-eye-movement (REM) sleep behavior disorder (iRBD). Methods: We fully sequenced 25 genes previously identified in GWASs of PD, in a total of 1,039 iRBD patients and 1,852 controls. The role of ra...

Objective Isolated (or idiopathic) rapid eye movement sleep behavior disorder (iRBD) is associated with dementia with Lewy bodies (DLB) and Parkinson's disease (PD). Biomarkers are lacking to predict conversion to a dementia or a motor‐first phenotype. Here, we aimed at identifying a brain‐clinical signature that predicts dementia in iRBD. Methods...

Idiopathic hypersomnia is a poorly defined nosological entity and has important phenotype heterogeneity. Moreover, diagnosing idiopathic hypersomnia is challenging as patients can report significant symptoms but may not meet diagnostic criteria on standard objective tests. Advanced analyses of electroencephalographic (EEG) activity could provide ob...

Restless legs syndrome is a relatively common neurological disorder in adults. In childhood, however, its prevalence and genetic contribution are still largely unknown. The objectives of this study were to assess the prevalence of restless legs syndrome (RLS) during childhood and adolescence in a large population‐based cohort and evaluate the degre...

Objective To examine the role of genes identified through genome-wide association studies (GWASs) of Parkinson disease (PD) in the risk of isolated rapid-eye-movement (REM) sleep behavior disorder (iRBD). Methods We fully sequenced 25 genes previously identified in GWASs of PD, in a total of 1,039 iRBD patients and 1,852 controls. The role of rare...

Objective To study the role of GBA variants in the risk for isolated rapid-eye-movement (REM)-sleep behavior disorder (iRBD) and conversion to overt neurodegeneration. Methods A total of 4,147 individuals were included: 1,061 iRBD patients and 3,086 controls. GBA was fully sequenced using molecular inversion probes and Sanger sequencing. We analyz...

Impulse control disorders (ICDs) in Parkinson's disease (PD) are defined as a failure to resist an “urge” to behave in a way that may be debilitating for oneself or others. The suggested immobilization test (SIT) has been developed to assess the “urge” to move and support the diagnosis of restless legs syndrome (RLS) in the general population and i...

Background Idiopathic rapid eye movement sleep behavior disorder is associated with increased risk of neurodegeneration, but the temporal evolution of regional perfusion, a marker of cerebral activity, has not been characterized. The objective of the current study was to study longitudinal regional perfusion in patients with idiopathic rapid eye mo...

Mutations in the sphingomyelin phosphodiesterase 1 (SMPD1) gene were reported to be associated with Parkinson disease (PD) and dementia with Lewy bodies (DLB). In the current study we aimed to evaluate the role of SMPD1 variants in iRBD. SMPD1 and its untranslated regions were sequenced using targeted next-generation sequencing in 959 iRBD patients...

Background: More than 75% of Parkinson's disease (PD) patients will develop dementia. Previous studies on the cognitive predictors of dementia in PD had some methodological limitations and the cognitive tests identified as good predictors vary greatly. Objective: This prospective cohort study aims to identify the optimal cognitive predictors of...

This cross-sectional study examined the moderating role of support from three key figures (mothers, teachers, friends) in the association between peer victimization and parasomnias in childhood. The sample consisted of 1150 children aged 8 years who attended elementary school. Controlling for potential confounders, hierarchical multiple regressions...

Background Attention-Deficit/Hyperactivity Disorder (ADHD) often comorbid with sleep disturbances can produce profound disruption in daily life and impact negatively on quality of life of both the child and family. However, the temporal relationship between ADHD and sleep impairment is unclear, as are underlying common brain mechanisms. Methods Th...

Characterizing the effects of obstructive sleep apnea (OSA) on the aging brain could be key in our understanding of neurodegeneration in this population. Our objective was to assess white matter properties in newly diagnosed and untreated adults with mild to severe OSA. Sixty‐five adults aged 55 to 85 were recruited and divided into three groups: c...

Mutations in the sphingomyelin phosphodiesterase 1 (SMPD1) gene were reported to be associated with Parkinson disease (PD) and dementia with Lewy bodies (DLB). The majority of patients with isolated rapid eye movement sleep behavior disorder (iRBD) develop PD or DLB later in life, suggesting that iRBD is a prodromal phase of these two conditions. I...

Study Objectives The evolution of sleep bruxism manifestations and their co-occurrence with separation anxiety in early childhood remain unclear. Our threefold aim was to: (1) describe developmental sleep bruxism trajectories in early childhood, (2) investigate co-occurrences between trajectories of sleep bruxism and separation anxiety, and (3) det...

Objective: The TMEM175/GAK/DGKQ locus is the 3rd strongest risk locus in genome-wide association studies (GWAS) of Parkinson disease (PD). We aimed to identify the specific disease-associated variants in this locus, and their potential implications. Methods: Full sequencing of TMEM175/GAK/DGKQ, followed by genotyping of specific associated varia...

Contexte théorique La pertinence clinique des cauchemars (CM) est de plus en plus reconnue, mais leurs corrélats neuronaux demeurent peu étudiés. Des travaux récents de notre laboratoire utilisant la tomographie à émission monophotonique (TEMP) suggèrent que la sévérité des CM est négativement associée à l’activité à l’éveil de régions corticales i...

Somnambulism is a non-rapid eye movement sleep parasomnia with potential for significant injury as well as functional nighttime and daytime impairment. Clonazepam is frequently used as first line pharmacotherapy. However, the optimal treatment of somnambulism has not been established. In this article, we present the cases of two patients with sever...

Idiopathic hypersomnia (IH) is characterized by excessive daytime sleepiness but, in contrast to narcolepsy, does not involve cataplexy, sleep-onset REM periods, or any consistent hypocretin-1 deficiency. The pathophysiological mechanisms of IH remain unclear. Because of the involvement of the default-mode network (DMN) in alertness and sleep, our...

Objective We aimed to study the role of coding VPS13C variants in a large cohort of late-onset PD (LOPD) patients. Methods VPS13C and its untranslated regions were sequenced using targeted next-generation sequencing in 1,567 PD patients and 1,667 controls from 3 cohorts. Association tests of rare potential homozygous and compound heterozygous vari...

REM Behavior Disorder (RBD) is now recognized as the prodromal stage of α-synucleinopathies such as Parkinson's disease (PD). In this paper, we describe deep learning models for diagnosis/prognosis derived from a few minutes of eyes-closed resting electroencephalography data (EEG) collected at baseline from idiopathic RBD patients (n = 121) and hea...

Nightmares are associated with psychopathology symptoms and emotional dysregulation. The neurophysiological correlates of nightmares are largely unknown, but some research suggests that nightmare distress (NMD), a variable strongly associated with psychopathology, is negatively correlated with brain activity in frontal regions (medial prefrontal co...

Background: Mutations in the glucocerebrosidase (GBA) gene are strongly associated with REM sleep behavior disorder (RBD). It is unclear whether GBA mutations might affect clinical phenotype or rate of phenoconversion to parkinsonism or dementia. Methods: We sequenced GBA in polysomnographic-proven idiopathic RBD (iRBD) patients. The effect of GBA...

Les cauchemars sont un facteur de risque pour la psychopathologie et le suicide, mais les mécanismes cérébraux impliqués dans ceux-ci sont peu connus. Une étude récente de notre laboratoire utilisant la tomographie à émission monophotonique (TEMP) suggère que la fréquence et la détresse liée aux cauchemars sont négativement associées à l'activité d...

Study objectives: Recent studies show that obstructive sleep apnea (OSA) is a possible contributor to abnormal cognitive decline in older adults. These new observations create the need to identify older adults with OSA who are at risk of the developing dementia if not treated. This study's goal was to verify whether self-reported cognitive complai...

We aimed to investigate cortical and subcortical brain alterations in Parkinson’s disease patients with polysomnography-confirmed REM sleep behavior disorder (RBD). Thirty Parkinson’s disease patients, including 15 patients with RBD, were recruited and compared to 41 healthy controls. Surface-based cortical and subcortical analyses were performed o...

Study objectives: Growing evidence suggests that nightmares have considerable adverse effects on waking behavior, possibly by increasing post-sleep negative emotions. Dysphoric reactions to nightmares are one component of nightmare severity for which the neural correlates are unknown. Here, we investigate possible neural correlates of nightmare se...

Introduction: Idiopathic rapid eye movement sleep behavior disorder (iRBD) is a prodromal stage of Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Depressive and anxiety symptoms are frequent features of PD, DLB and iRBD, and some studies suggest that depressive symptoms are a marker for neurodegeneration in iRBD. However, the pathop...

Obstructive sleep apnea (OSA) predominantly during rapid eye movement (REM) sleep may have impacts on brain health, even in milder OSA cases. Here, we evaluated whether REM sleep OSA is associated with abnormal daytime cerebral functioning using high-resolution single-photon emission computed tomography (SPECT). We tested 96 subjects (25 F, age: 65...

Obstructive sleep apnoea increases the risk for mild cognitive impairment and dementia. The present study aimed to characterise the ability of two cognitive screening tests, the Mini-Mental State Examination and the Montreal Cognitive Assessment, to detect mild cognitive impairment in adults aged 55–85 years with and without obstructive sleep apnoe...

Idiopathic rapid eye movement sleep behavior disorder (RBD) is a serious risk factor for neurodegenerative processes such as Parkinson’s disease (PD). We investigate the use of EEG algorithmic complexity derived metrics for its prognosis. We analyzed resting state EEG data collected from 114 idiopathic RBD patients and 83 healthy controls in a long...

Restless Legs syndrome (RLS) is a common sleep disorder for which the genetic contribution remains poorly explained. In 2007, the first large scale genome wide association study (GWAS) identified three genomic regions associated with RLS. MEIS1, BTBD9 and MAP2K5/SKOR1 are the only known genes located within these loci and their association with RLS...

Rapid eye movement (REM) sleep behaviour disorder (RBD) is a parasomnia that is characterized by loss of muscle atonia during REM sleep (known as REM sleep without atonia, or RSWA) and abnormal behaviours occurring during REM sleep, often as dream enactments that can cause injury. RBD is categorized as either idiopathic RBD or symptomatic (also kno...

Type 1 narcolepsy (T1N) is a neurological condition, in which the death of hypocretin-producing neurons in the lateral hypothalamus leads to excessive daytime sleepiness and symptoms of abnormal Rapid Eye Movement (REM) sleep. Known triggers for narcolepsy are influenza-A infection and associated immunization during the 2009 H1N1 influenza pandemic...

This study examined the moderating role of parental behaviors in the longitudinal link between peer victimization and sleep problems during preschool. The sample consisted of 1,181 children (594 girls) attending day care between the ages of 3 and 6 years. Participants were part of the Quebec Longitudinal Study of Child Development, a longitudinal s...

Background: MAPT haplotypes are associated with PD, but their association with REM-sleep behavior disorder (RBD) is unclear. Methods: Two cohorts were included: A) PD (n=600), RBD (n=613) patients and controls (n=981), B) DLB patients with RBD (n=271) and controls (n=950). MAPT-associated variants and the entire coding sequence of MAPT was analyzed...

Introduction Obstructive sleep apnea increases the risk for mild cognitive impairment and dementia. Identifying patients who will present cognitive decline is crucial in treatment decision, particularly for patients with no or mild daytime sleepiness. We aim to characterize the ability of two cognitive screening tests, the Mini-Mental State Examina...

Introduction Chronic insomnia disorder (CID) and restless leg syndrome (RLS) are two common sleep disorders in the general population and are frequently comorbid. Two recent genome-wide assocaition studies (GWAS) have suggested that MEIS1 gene is a shared genetic basis between these two disorders, which is an intriguing finding that can change our...

Introduction Mild cognitive impairment (MCI), which is a prodrome of Alzheimer’s disease (AD), offers the opportunity to identify AD-related markers before the dementia phase. Cholinergic basal forebrain neurons, which degenerate early in AD, play a major role during Rapid-Eye-Movement (REM) sleep, at a time when several other neuronal systems are...

Introduction Sleepwalking is a common arousal parasomnia affecting between 2%-4% of the general adult population. Although factors that intensify or disrupt sleep have been shown to increase the likelihood and intensity of somnambulism in predisposed individuals, little is known about the factors sleepwalkers themselves view as most likely to preci...

Objective: To investigate cortical and subcortical gray matter abnormalities underlying cognitive impairment in patients with REM sleep behavior disorder (RBD) with or without mild cognitive impairment (MCI). Methods: Fifty-two patients with RBD, including 17 patients with MCI, were recruited and compared to 41 controls. All participants underwe...

Objective: We describe the progression of cognitive decline and identify the predictive values of cognitive tests in three groups of REM sleep behavior disorder (RBD) patients classified at their last follow-up as having Parkinson's disease (PD), dementia with Lewy bodies (DLB), or still-idiopathic. Methods: Patients (n = 109) underwent polysomn...

Although placebo analgesia is a well-recognized phenomenon with important clinical implications, the possibility that placebo effects occur during sleep has received little attention. This experimental study examined whether responsiveness to acute heat pain stimuli applied during sleep could be reduced following a placebo conditioning procedure ad...

Although placebo analgesia is a well-recognized phenomenon with important clinical implications, the possibility that placebo effects occur during sleep has received little attention. This experimental study examined whether responsiveness to acute heat pain stimuli applied during sleep could be reduced following a placebo conditioning procedure ad...

Background: Individuals with rapid eye movement (REM)-sleep behavior disorder (RBD) are likely to progress to synucleinopathies, mainly Parkinson's disease (PD), dementia with Lew-bodies (DLB) and multiple system atrophy (MSA). The genetics of RBD only partially overlaps with PD and DLB, and the role of LRRK2 variants in risk for RBD is still not c...

Study objectives The present study assessed brain perfusion patterns with single photon emission computed tomography (SPECT) during sleepwalkers’ post-sleep deprivation slow-wave sleep and resting-state wakefulness. Methods Following a 24-hr period of sleep deprivation, 10 sleepwalkers and 10 sex- and age-matched controls were scanned with a high-...

Objective Idiopathic REM sleep behavior disorder (RBD) is a serious risk factor for neurodegenerative processes such as Parkinson’s disease (PD). We investigate the use of EEG algorithmic complexity derived metrics for its prognosis. Methods We analyzed resting state EEG data collected from 114 idiopathic RBD patients and 83 healthy controls in a...