Alexandre Dumais

• MD PhD
• Professor (Associate) at Université de Montréal

Background/Objectives: Violent behaviors are uncommon in patients with schizophrenia (Sch), but when present, exacerbate stigma and challenge treatment. The following study aimed to identify the structural abnormalities associated with violent behaviors in Sch by implementing a validated tool specifically designed to evaluate violent behaviors in p...

The association between family violence and the COVID-19 pandemic remains complex. This meta-analysis aimed to determine trends in the observed changes in family violence comparing the pre-pandemic period to the pandemic period. A systematic search was performed in electronic databases to identify all relevant research reporting on COVID-19 and fam...

Background: The advent of virtual reality in psychiatry presents a wealth of opportunities for a variety of psychopathologies. Avatar Interventions are dialogic and experiential treatments integrating personalized medicine with virtual reality (VR), which have shown promising results by enhancing the emotional regulation of their participants. Nota...

Objective: Despite the efficacy of current therapies, a significant proportion of patients with schizophrenia, a complex mental disorder marked by both positive (present) and negative (absent) symptoms, are considered to have treatment-resistant schizophrenia. Avatar therapy (AT) allows patients to interact with a three-dimensional representation...

Background: The dual diagnosis of cannabis use disorder (CUD) and severe mental disorder (SMD) results in clinically complex individuals. Cannabis use is known to have negative consequences on psychiatric symptoms, medication compliance, and disease prognosis. Moreover, the effectiveness of currently available psychotherapeutic treatments is limite...

Background: An increasing body of literature highlights the integration of machine learning with genomic data in psychiatry, particularly for complex mental health disorders such as schizophrenia. These advanced techniques offer promising potential for uncovering various facets of these disorders. A comprehensive review of the current applications...

Objectif Le cannabis est la drogue la plus consommée au sein de la population générale, mais sa prévalence d’usage reste plus élevée chez les personnes souffrant de troubles mentaux graves. De plus, les données actuelles démontrent les effets délétères du cannabis sur la symptomatologie de ces maladies. L’étude transversale ci-présente vise donc à...

Purpose COVID-19 pandemic-related restrictions have significantly changed the environment and the delivery of direct care in all health services, including psychiatric hospitals. The aim of the study is two-fold: 1) to retrospectively assess the incidence of seclusion and mechanical restraint in a Quebec mental health hospital over 4 years; and 2)...

(1) Background: Approximately 1% of the global population is affected by schizophrenia, a disorder marked by cognitive deficits, delusions, hallucinations, and language issues. It is associated with genetic, neurological, and environmental factors, and linked to dopaminergic hyperactivity and neurotransmitter imbalances. Recent research reveals tha...

The aims of this systematic review and meta-analysis were to evaluate the risk of inmates with mental disorder of being placed into disciplinary confinement (DC) and its effect on mental health. A systematic search of studies was performed in PubMed, PsycINFO, Web of Science, and Google Scholar. The meta-analysis was conducted using random-effects...

Avatar therapy (AT) is a novel virtual reality-based psychotherapy that has been developed to treat auditory verbal hallucinations (AVH) in treatment-resistant schizophrenia. Various psychotherapeutic components, such as emotions and sense of presence, could contribute to clinical outcomes. However, the interplay between sense of presence, emotions...

Background Pain is a complex and multifaced sensory and emotional experience. Virtual reality (VR) has shown promise in reducing experimental pain and chronic pain. This study examines an immersive VR environment initially designed for endometriosis patients, which demonstrated short-term analgesic effects. The research aims to determine the impact...

Background: An increasing body of literature highlights the integration of machine learning with genomic data in psychiatry, particularly for complex mental health disorders such as schizophrenia. These advanced techniques offer promising potential for uncovering various facets of these disorders. A comprehensive review of the current applications...

Background An increasing body of literature highlights the integration of machine learning with genomic data in psychiatry, particularly for complex mental health disorders such as schizophrenia. These advanced techniques offer promising potential for uncovering various facets of these disorders. A comprehensive review of the current applications o...

Avatar therapy (AT) is a novel virtual reality-based psychotherapy that has been developed to treat auditory verbal hallucinations (AVH) in treatment-resistant schizophrenia patients. Various psychotherapeutic components, such as emotions and sense of presence, could contribute to clinical outcomes. However, the interplay between sense of presence,...

Objective: Recreational cannabis legalization (RCL) is expanding rapidly. RCL's effects on mental health issues are of particular concern because cannabis use is more frequent among people receiving psychiatric care and is associated with several psychiatric disorders. The authors conducted a scoping review to examine the evidence and discern gaps...

BACKGROUND The dual diagnosis of cannabis use disorder (CUD) and severe mental disorder (SMD) results in clinically complex individuals. Cannabis use is known to have negative consequences on psychiatric symptoms, medication compliance, and disease prognosis. Moreover, the effectiveness of currently available psychotherapeutic treatments is limited...

Background The dual diagnosis of cannabis use disorder (CUD) and severe mental disorder (SMD) results in clinically complex individuals. Cannabis use is known to have negative consequences on psychiatric symptoms, medication compliance, and disease prognosis. Moreover, the effectiveness of currently available psychotherapeutic treatments is limited...

Background: Psychotherapeutic approaches such as Avatar Therapy (AT) are novel therapeutic attempts to help patients diagnosed with treatment-resistant schizophrenia. Qualitative analyses of immersive sessions of AT have been undertaken to enhance and refine the existing interventions taking place in this therapy. To account for the time-consuming...

Background Schizophrenia is associated with an increased risk of aggressive behaviour, which may partly be explained by illness-related changes in brain structure. However, previous studies have been limited by group-level analyses, small and selective samples of inpatients and long time lags between exposure and outcome. Methods This cross-section...

The Signature Biobank is a longitudinal repository of biospecimen, psychological, sociodemographic, and diagnostic data that was created in 2012. The Signature Consortium represents a group of approximately one hundred Quebec-based transdisciplinary clinicians and research scientists with various expertise in the field of psychiatry. The objective...

This meta-analysis investigates auditory steady-state responses (ASSRs) as potential biomarkers of schizophrenia, focusing on previously unexplored clinical populations, frequencies, and variables. We examined 37 studies, encompassing a diverse cohort of 1788 patients with schizophrenia, including 208 patients with first-episode psychosis, 281 at-r...

Considering the harmful effects of cannabis on individuals with a severe mental disorder and the limited effectiveness of current interventions, this case report showcases the beneficial results of a 10-session Avatar intervention for cannabis use disorder (CUD) on a polysubstance user with a comorbid schizoaffective disorder. Virtual reality allow...

(1) Background: Approximately 30% of schizophrenia patients are known to be treatment-resistant. For these cases, more personalized approaches must be developed. Virtual reality therapeutic approaches such as avatar therapy (AT) are currently undergoing investigations to address these patients’ needs. To further tailor the therapeutic trajectory of...

1) Background: Avatar Therapy (AT) is currently being studied to help patients suffering from treatment-resistant schizophrenia. Facilitating annotations of immersive verbatims in AT by using classification algorithms could be an interesting avenue to reduce the time and cost of conducting such analysis and adding objective quantitative data in the...

Considering the harmful effects of cannabis on individuals with a severe mental disorder and the limited effectiveness of current interventions, this case report showcases the beneficial results of a 10-session Avatar intervention for cannabis use disorder (CUD) on a polysubstance user with a comorbid schizoaffective disorder. Virtual reality allow...

Introduction Auditory verbal hallucinations (AVH), which often present in individuals with schizophrenia, can cause great psychological distress. Although antipsychotic medication can reduce AVH, 30% of patients will be resistant. Treatment resistance could be associated with important consequences, and there are only few treatment alternatives. Un...

Introduction Recent longitudinal studies point towards the existence of a positive relationship between cannabis use and violence in people with severe mental disorders. However, the existence of a dose-response relationship between the frequency and/or the severity of cannabis use and violence has seldom been investigated. Objectives This study a...

Introduction Cannabis use disorder (CUD) is a complex issue, even more so when it is comorbid with a psychotic disorder or a mood disorder. Indeed, this population seems more vulnerable to this substance since the incidence of developing CUD is five to six times higher. Psychotherapies have only shown a modest short-term effect that is not maintain...

Context: Emotion regulation is a set of processes responsible for controlling, evaluating and adjusting reactions to achieve a goal. Results derived from magnetic resonance imaging agreed on the involvement of frontal and limbic structures in this process. Findings using cognition and physiology interactions are still scarce but suggest a role of...

Background Emotional responses are an important component of psychotherapeutic processes. Avatar therapy (AT) is a virtual reality-based therapy currently being developed and studied for patients suffering from treatment resistant schizophrenia. Considering the importance of identifying emotions in therapeutical processes and their impact on the th...

This meta-review aimed to summarize the current state of knowledge provided by meta-analyzes on the efficacy of psychotherapies for substance use disorders. A systematic search was performed in PubMed, PsycINFO, Web of Science and Google Scholar. Meta-analyzes were included if they quantitatively examined the efficacy of a psychotherapy on substanc...

Citation: Bernard-Arevalo, S.-P.; Laforce, R.J.; Khayat, O.; Bouchard, V.; Bruneau, M.-A.; Brunelle, S.; Caron, S.; Chamelian, L.; Chénard, M.; Côté, J.-F.; et al. Clinical Assessment of Judgment in Adults and the Elderly: Development and Validation of the Three Domains of Judgment Test-Clinical Version (3DJT-CV). Abstract: (1) Background: This art...

(1) Background: The therapeutic mechanisms underlying psychotherapeutic interventions for individuals with treatment-resistant schizophrenia are mostly unknown. One of these treatment techniques is avatar therapy (AT), in which the patient engages in immersive sessions while interacting with an avatar representing their primary persistent auditory...

Cannabis use disorder (CUD) is a complex issue, even more so when it is comorbid with a severe mental disorder (SMD). Available interventions are at best slightly effective, and their effects are not maintained over time. Therefore, the integration of virtual reality (VR) may increase efficacy; however, it has not yet been investigated in the treat...

Purpose: COVID-19 pandemic-related restrictions have significantly changed the environment and the delivery of direct care in all health services, including psychiatric hospitals. The aim of the study is two-fold: 1) to retrospectively assess the prevalence of seclusion and mechanical restraint in a Quebec mental health hospital over 4 years; and 2...

Abstract: (1) Background: Very little is known about the inner therapeutic processes of psychotherapy interventions for patients suffering from treatment-resistant schizophrenia. Avatar therapy (AT) is one such modalities in which the patient is undergoing immersive sessions in which they interact with an Avatar representing their main persistent a...

Avatar Therapy has a significant impact on symptoms, beliefs, and quality of life of patients with treatment-resistant schizophrenia. However, little is known about how these changes are implemented into their lives and to which aspects of their lives these improvements relate. Ten consecutive patients enrolled in an ongoing clinical trial were ass...

Introduction: Recent longitudinal studies point toward the existence of a positive relationship between cannabis use and violence in people with severe mental disorders (SMD). However, the existence of a dose-response relationship between the frequency/severity of cannabis use and violence has seldom been investigated. Therefore, this study aims to...

The objective of this cross-sectional study was to identify cannabis-related features and other characteristics predictive of violence using a data-driven approach in patients with severe mental disorders (SMDs). A Least Absolute Shrinkage and Selection Operator regularization regression model was used on the database consisting of 97 patients with...

Background Ineffective cannabis regulatory frameworks such as prohibition have sparked interest in alternative solutions to reduce individual and societal harms. While it has been suggested that the recreational legalization process has yielded early successes, the relatively recent implementation of the novel policies has provided a modest time fr...

SSRN is an open-access online preprint community providing valuable services to leading academic schools and government institutions. Specializing primarily in social sciences, including economics, law, corporate governance, and humanities, SSRN is branching out in to other science disciplines providing opportunities for scholars to post their earl...

Avatar Therapy (AT) is a modern therapeutic alternative for patients with schizophrenia suffering from persistent auditory verbal hallucinations. Its intrinsic therapeutical process is currently qualitatively analyzed via human coders that annotate session transcripts. This process is time and resource demanding. This creates a need to find potenti...

This study aimed to investigate the association between past-reported violent/aggressive behaviors and brain functional connectivity in male patients suffering from schizophrenia using a task modeling the interaction between negative emotion processing and response inhibition. Forty-four male patients with schizophrenia and twenty-two healthy male...

Purpose The COVID-19 pandemic led to exacerbation of mental health symptoms and deterioration in psychological well-being in individuals suffering from schizophrenia. The primary objective of this study is to evaluate the impacts of the COVID-19 pandemic on patients suffering from treatment-resistant schizophrenia (TRS) with auditory verbal halluci...

Background Auditory hallucinations in patients with psychotic disorders may be very distressing. Unfortunately, a large proportion of individuals are resistant to pharmacological interventions and the gold-standard cognitive-behavioral therapy for psychosis offers at best modest effects. To improve therapeutic outcomes, several therapies have been...

The legalization of cannabis raises many queries, one of which regards the criminal liability of users under the influence of cannabis when crimes against the person are committed. This perspective review consequently aims to examine the defense of mental disorder (also referred to as the insanity defense) in Canadian criminal law and revise court...

Background: The association between cannabis and cognitive functions has been thoroughly studied in psychotic disorders, but conflictual/paradoxical results have emerged. This critical meta-review examined the magnitude of effects of cannabis on neurocognitive functions in patients with psychotic disorders provided by meta-analyses and evaluated th...

Purpose This study aims to develop immersive scenarios (immersive videos) to foster generalization of learning while addressing social cognition, a factor associated to violence in schizophrenia. The authors sought to develop immersive videos that generate a sense of presence; are socially realistic; and can be misinterpreted and, if so, lead to an...

While research focus remains mainly on psychotic symptoms, it is questionable whether we are placing enough emphasis on improving the quality of life (QoL) of schizophrenia patients. To date, the predictive power of QoL remained limited. Therefore, this study aimed to accurately predict the QoL within schizophrenia using supervised learning methods...

Background: Cannabis is among the most consumed psychoactive substances world-wide. Considering changing policy trends regarding the substance, it is crucial to understand more clearly its potential acute and residual adverse effects from a public health viewpoint. Cognitive function is one of the targeted areas with conflicting findings. This met...

Objective: Although schizophrenia patients are at a heightened risk of exhibiting violent behaviours compared to the general population, few functional neuroimaging studies have explored the aberrant neurocircuitry un- derpinning such behaviours. This study aimed to identify disrupted resting-state activity and functional con- nectivity in schizoph...

Given the increasing literature on forensic assertive community treatment (FACT), we conducted a systematic review and meta-analysis to explore the effectiveness of FACT among justice-involved individuals with severe mental illness. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Sixteen stu...

Abstract Background:A growing body of literature has detailed the use of qualitative analyses to measure the therapeutic processes and intrinsic effectiveness of psychotherapies, which yield small databases. Nonetheless, these approaches have several limitations and machine learning algorithms are needed. Objective:The objective of this study is...

Objectifs La schizophrénie, en particulier la schizophrénie résistante aux traitements (SRT), est considérée comme l’un des troubles psychiatriques les plus invalidants en termes d’effets indésirables sur la qualité de vie (QV) des patients. La QV subjective est devenue une cible particulièrement cruciale qui devrait être améliorée avec le traiteme...

Objectives. The COVID-19 pandemic has had many public health impacts, especially on vulnerable individuals including adults with neurocognitive disorders (NCD). With increasing literature, this systematic literature review aimed to address the mental health effects of COVID-19 on people with NCD in addition to examine the impact of the pandemic on...

Introduction Mounting evidence has begun establishing a link between cannabis use and adverse psychotic outcomes in patients affected by psychosis. However, we have yet to determine if this relationship is maintained when controlling for important confounding variables. As such, the following systematic review aims to investigate if the association...

Les mesures de contention et d’isolement (MCI) en centre de réadaptation pour jeunes en difficultés sont controversées et employées sur une base régulière. Bien que l’utilisation des MCI soit balisée par des lois, le stress ou la fatigue de l’éducateur est susceptible de teinter le processus décisionnel menant à leur application. Considérant les ef...

Objectives Schizophrenia, particularly treatment-resistant schizophrenia (TRS), is one of the most disabling psychiatric disorders in terms of adverse effects on the quality of life (QOL) of patients. Subjective QOL has become a particularly crucial target that should be improved with treatment, since improved QOL may lead to recovery in patients w...

Introduction Schizophrenia is a chronic and severe mental disorder. While research focus remains mainly on negative outcomes, it is questionable whether we are placing enough emphasis on improving their sense of well-being and functioning. This could be accessed through the study of the quality of life (QoL). To date, QoL prediction models mainly f...

Past evidence suggests that hippocampal subregions, namely the anterior and posterior parts, may be engaged in distinct networks underlying the memory functions which may be altered in patients with schizophrenia. However, of the very few studies that have investigated the hippocampal longitudinal axis subdivisions functional connectivity in patien...

Purpose Since conduct problems (CP) vary distinctly across youths, better subtyping CP may be an important vehicle to study specific risk factors associated to differential patterns of CP. In a sample of 63,196 adolescents, we employed a two-step method to the identify such CP patterns and to help classify youths based on several sociodemographic a...

The gold-standard cognitive–behavioral therapy (CBT) for psychosis offers at best modest effects. With advances in technology, virtual reality (VR) therapies for auditory verbal hallucinations (AVH), such as AVATAR therapy (AT) and VR-assisted therapy (VRT), are amid a new wave of relational approaches that may heighten effects. Prior trials have s...

Objective Since the therapeutic processes of Avatar Therapy remain equivocal, the current study aims to further extend our previous findings by analyzing the evolution of the avatars’ and patients’ speech and changes in patient responses as sessions progressed. Design Eighteen patients with treatment‐resistant schizophrenia were selected from two...

Background The high rates of suicidal behaviours (SBs) in psychiatric populations remain an important preoccupation to address. The literature reveals emotional instability as an important risk factor for SBs. However, the neural mechanisms underpinning this risk factor have never been investigated in schizophrenia patients with SBs. The following...

Although recent studies have shown a moderately strong association between cannabis use and violence among people with severe mental disorders, the direction of this association has not been investigated prospectively in a population with schizophrenia. Therefore, this study aims to determine, using cross-lag models, whether a temporal relationship...

Background Restraint and seclusion (R&S) are controversial methods of intervention aimed at protecting children from immediate harm in residential treatment centers (RTC). Previous studies have mainly focused on situational factors and youth characteristics to predict its use. Objectives This study sought to evaluate the role other potential predi...

Background: Combining cognitive behavioral therapy (CBT) for psychosis with another psychosocial intervention comprising virtual reality (VR)-assisted therapy (VRT) may improve targeted outcomes in treatment-resistant schizophrenia patients. Methods: Ten participants having followed CBT were part of our comparative clinical trial comparing VRT t...

Past functional magnetic resonance imaging on antisocial subjects have shown important inconsistencies and methodological problems (e.g. heterogeneity in fMRI tasks domain, small sample sizes, analyses on regions-of-interest). We aimed to conduct a meta-analysis of whole-brain fMRI studies on antisocial individuals based on distinct neurocognitive...

Recidivism among released inmates is associated with a substantial societal burden given the financial and medical consequences of victimization. Among incarcerated North Americans, approximately 7% are housed in solitary confinement (SC). Studies show SC can lead to psychological deterioration and dispute it can effectively reduce institutional mi...

There has been a shift surrounding societal and legal perspectives on cannabis reflecting changing public attitudes towards the perceived safety and social acceptability of cannabis use. With cannabis liberalization internationally, the focus of most cannabis-related harms has been on effects with users themselves. Harm-to-others including injuries...

Objectives To systematically review and meta-analyze the psychological effects and mortality rate in inmates having been exposed to solitary confinement in correctional settings. Methods PubMed, PsycINFO, Web of Science, and Google Scholar were searched using keywords describing solitary confinement in combination with keywords for psychological o...

Background Among all diseases globally, mental illnesses are one of the major causes of burden. As many people are resistant to conventional evidence-based treatments, there is an unmet need for the implementation of novel mental health treatments. Efforts to increase the effectiveness and benefits of evidence-based psychotherapy in psychiatry have...

BACKGROUND Avatar therapy (AT) is a modern therapeutic alternative for schizophrenic patients with persistent auditory hallucinations. The effectiveness of psychotherapy is generally measured by semi-structured interviews or self-reported questionnaires. To complement, an increasing number of research teams have started to use qualitative analyses,...

BACKGROUND Among all diseases globally, mental illnesses are one of the major causes of burden. As many people are resistant to conventional evidence-based treatments, there is an unmet need for the implementation of novel mental health treatments. Efforts to increase the effectiveness and benefits of evidence-based psychotherapy in psychiatry have...

Objective: The aim of this meta-analysis was to investigate the extent to which cannabis use among youths is associated with the risk of perpetrating physical violence. Methods: Searches were conducted in PubMed, PsycINFO, Web of Science, and Google Scholar for articles published from the inception of each database to July 2019. All studies that...

The aim of this meta‐analysis was to examine the association between any mental health problem and the risk of being placed into solitary confinement in correctional settings. PubMed, PsycINFO, Web of Science and Google Scholar were searched from each database’s inception date to November 2019. All publications assessing both mental health problems...

Background: Despite individuals with schizophrenia being at an elevated risk of violence compared to the general population, limited efforts have been invested in investigating the neurobiological etiology explaining the increase. Among the few studies examining functional disruptions pertaining to violent schizophrenia patients using fMRI, only on...

This study aims to identify the factors that need to be considered in the implementation of the integrated psychological treatment (IPT), a cognitive-behavioral group approach for individuals with schizophrenia, in correctional and forensic psychiatric settings. To meet this objective, a multiple case study ( n = 2) was conducted. Stakeholders invo...

Youth violence is a complex and multifactorial issue that has severe health and social consequences. While treatment options exist to treat/reduce violence in at-risk populations such as schizophrenia, there remains limitations in the efficacy of current interventions. Virtual reality (VR) appears to be a unique possibility to expose offenders and...

Objective: It has long been assumed that paranoid ideation may stem from an aberrant limbic response to threatening stimuli. However, results from functional neuroimaging studies using negative emotional stimuli have failed to confirm this assumption. One of the potential reasons for the lack of effect is that study participants with psychosis may...

Background: In youth, anxiety-depressive traits (ADT) and trait-aggression (TA) are important risk factors of exhibiting maladaptive behaviors in adulthood (i.e. violence and substance use). However, the developmental co-occurrence of these traits in youth remains unknown. We thus sought to investigate the developmental trajectories of ADT and TA...

Children placed in residential treatment centers (RTCs) typically present challenging behavior including aggression. In this context, restraint and seclusion (R&S) are seen as “last resort” strategies for educators to manage youth aggression. The use of R&S is controversial, as they can lead to psychological and physical consequences for both the c...