Departement de psychologie

Approximately 30 to 50% of people suffering from Gilles de la Tourette Syndrome (GTS) also fulfill diagnostic criteria for obsessive-compulsive disorder (OCD). Despite this high degree of comorbidity, very few studies have addressed the question of obsessive-compulsive symptoms (OCS) in GTS patients using specific brain event-related potentials (ERP) responses. The aim of the current study was to quantify neurocognitive aspects of comorbidity, using ERPs. Fourteen adults with GTS (without OCD) were compared to a group of 12 participants with GTS and comorbid obsessivecompulsive symptoms (GTS + OCS), to a group of 15 participants with OCD and to a group of 14 control participants without neurological or psychiatric problems. The P200 and P300 components were recorded during a visual counting oddball task. Results showed intact P200 amplitude in all groups, whilst the P300 amplitude was affected differentially across groups. The P300 oddball effect was reduced in participants in both OCD and GTS + OCS groups in the anterior region. However, the P300 oddball effect was significantly larger in participants of the GTS group compared to all other groups, mostly in the parietal region. These findings suggest that adults with GTS are characterized by enhanced working memory updating processes and that the superimposition of OCS can lead to a reduction of these processes. The discrepancy between our findings and results obtained in previous studies on GTS could reflect the modulating effect of OCS on late ERP components.

The Montreal Battery for the Evaluation of Amusia (MBEA; Peretz, Champod, & Hyde Annals of the New York Academy of Sciences, 999, 58-75, 2003) is an empirically grounded quantitative tool that is widely used to identify individuals with congenital amusia. The use of such a standardized measure ensures that the individuals tested will conform to a specific neuropsychological profile, allowing for comparisons across studies and research groups. Recently, a number of researchers have published credible critiques of the usefulness of the MBEA as a diagnostic tool for amusia. Here we argue that the MBEA and its online counterpart, the AMUSIA tests (Peretz et al. Music Perception, 25, 331-343, 2008), should be considered steps in a screening process for amusia, rather than standalone diagnostic tools. The goal of this article is to present, in detailed and easily replicable format, the full protocol through which congenital amusics should be identified. In providing information that has often gone unreported in published articles, we aim to clarify the strengths and limitations of the MBEA and to make recommendations for its continued use by the research community as part of the Montreal Protocol for Identification of Amusia.

Cochlear implants (CIs) restore a sense of hearing in deaf individuals. However, they do not transmit the acoustic signal with sufficient fidelity, leading to difficulties in recognizing emotions in voice and in music. The study aimed to explore the neurophysiological bases of these limitations. Design: Twenty-two adults (18 to 70 years old) with CIs and 22 agematched controls with normal hearing participated. Event-related potentials (ERPs) were recorded in response to emotional bursts (happy, sad, or neutral) produced in each modality (voice or music) that were for the most part correctly identified behaviorally. Results: Compared to controls, the N1 and P2 components were attenuated and prolonged in CI users. To a smaller degree, N1 and P2 were also attenuated and prolonged in music compared to voice, in both populations. The N1-P2 complex was emotion-dependent (e.g., reduced and prolonged response to sadness), but this was also true in both populations. In contrast, the later portion of the response, between 600 and 850 ms, differentiated happy and sad from neutral stimuli in normal hearing but not in CI listeners. Conclusions: The early portion of the ERP waveform reflected primarily the general reduction in sensory encoding by CI users (largely due to CI processing itself), whereas altered emotional processing (by CI users) could be found in the later portion of the ERP and extended beyond the realm of speech.

Occupational health has been recognized as an important long-term element of global economic development. However, statistical projections suggest dawn concerns on two levels: workers are aging and psychological well-being is deteriorating. To overcome its problems, strong leaders are sought for growing climate of trust as well as the well-being of their employees. This thesis aims to study authentic leadership as a contributor to the work climate and well-being of employees. To this end, two studies were performed. The first study aimed to translate and validate the Authentic Leadership Questionnaire in French. Confirmatory factor analyzes were performed on two samples of Quebec workers (N = 365, N = 859). The results obtained with a shortened version of the instrument show that a second-order structure with four associated factors provides the best fit to the data. The validity of the measure was further supported with authentic leadership correlates. The results revealed that leader's personal level of authenticity was positively related to the exercise of an authentic leadership, as well as with the leader's psychological well-being. Furthermore, the expected links between authentic leadership and followers' well-being, trust and interpersonal justice were supported. No support was found for the link between auto-reveled authentic leadership by the leader and his/her psychological well-being. The second study investigated a mediation model where authentic leadership has been purported to influence psychological well-being through its impact on work climate. Using a sample of 406 nurses, a time-lagged study design was employed to determine the mediational role of work climate in explaining the impact of authentic leadership. A mediation analysis with the use of a bootstrapping technique revealed that work climate mediated the relationship between authentic leadership and psychological well-being at work. These findings indicate that authentic leadership impacts the work climate in a positive manner; thereby, increasing levels of psychological well-being at work. Finally, in conclusion of this thesis endeavour, results are commented, contributions are presented, practical implications are suggested, limits are outlined, and future research are proposed.

Sleep fragmentation in infancy can burden a family by disrupting the sleep of all its members. However, there has been no longitudinal prospective investigation of the determinants of infant sleep fragmentation. We undertook such an investigation. New mothers (N = 106) completed questionnaires and were administered structured telephone interviews at three, six and 12 weeks postpartum. Pre- and postnatal maternal adjustment and sleep-related parental practices were evaluated as potential predictors of infants’ sleep fragmentation. Risk factors for infants sleeping less than six consecutive hours per night at 12 weeks were found to be mother’s depressed mood (OR = 1.55, p < .01), breastfeeding (OR = 6.40, p < .01) and room sharing (OR = 2.91, p < .05). The mother’s depressed mood and breastfeeding were also related to poor sleep consolidation when the latter was assessed as a continuous outcome (p < .01). This study identifies factors to target in sleep-focused interventions in families where the child’s sleep has become a problem.

Rapid eye movement (REM) sleep and dreaming may be implicated in cross-night adaptation to emotionally negative events. To evaluate the impact of REM sleep deprivation (REMD) and the presence of dream emotions on a possible emotional adaptation (EA) function, 35 healthy subjects randomly assigned to REMD (n = 17; mean age 26.4 ± 4.3 years) and control (n = 18; mean age 23.7 ± 4.4 years) groups underwent a partial REMD and control nights in the laboratory, respectively. In the evening preceding and morning following REMD, subjects rated neutral and negative pictures on scales of valence and arousal and EA scores were calculated. Subjects also rated dream emotions using the same scales and a 10-item emotions list. REMD was relatively successful in decreasing REM% on the experimental night, although a mean split procedure was applied to better differentiate subjects high and low in REM%. High and low groups differed – but in a direction contrary to expectations. Subjects high in REMD% showed greater adaptation to negative pictures on arousal ratings than did those low in REMD% (P < 0.05), even after statistically controlling sleep efficiency and awakening times. Subjects above the median on EAvalence had less intense overall dream negativity (P < 0.005) and dream sadness (P < 0.004) than subjects below the median. A correlation between the emotional intensities of the morning dream and the morning picture ratings supports a possible emotional carry-over effect. REM sleep may enhance morning reactivity to negative emotional stimuli. Further, REM sleep and dreaming may be implicated in different dimensions of cross-night adaptation to negative emotions.

ObjectivesThis retrospective cohort study investigates how parenting stress, measured at 4 months of age by use of a classic three-dimensional parent-reported scale (Parenting Stress Index, 4th Ed. or PSI-4), can predict anxiety symptoms and quality of sleep at 24 months in toddlers with congenital heart disease (CHD).Study DesignSixty-six toddlers with CHD followed at our cardiac neurodevelopmental follow-up clinic were included in this study. As part of their systematic developmental assessment program, parents completed questionnaires on their stress level (PSI-4) when their child was 4 months old, and on their child&#39;s anxiety symptoms and quality of sleep at 24 months. Eight multiple linear regression models were built on the two measures collected at 24 months using the PSI-4 scores collected at 4 months. For each measure, four models were built from the PSI-4 total score and its three subscales (Parental Distress, Parent-Child Dysfunctional Interaction, Difficult Child), c...

Objectives: This retrospective cohort study investigates how parenting stress, measured at 4 months of age by use of a classic three-dimensional parentreported scale (Parenting Stress Index, 4th Ed. or PSI-4), can predict anxiety symptoms and quality of sleep at 24 months in toddlers with congenital heart disease (CHD). Study Design: Sixty-six toddlers with CHD followed at our cardiac neurodevelopmental follow-up clinic were included in this study. As part of their systematic developmental assessment program, parents completed questionnaires on their stress level (PSI-4) when their child was 4 months old, and on their child's anxiety symptoms and quality of sleep at 24 months. Eight multiple linear regression models were built on the two measures collected at 24 months using the PSI-4 scores collected at 4 months. For each measure, four models were built from the PSI-4 total score and its three subscales (Parental Distress, Parent-Child Dysfunctional Interaction, Difficult Child), controlling for sex and socioeconomic status. Results: The PSI-4 Difficult Child subscale, which focuses on parenting anxiety related to the child's behavioral problems and poor psychosocial adjustment, accounted for 17% of the child's anxiety symptoms at 24 months. The two other PSI-4 subscales (Parental Distress and Parent-Child Dysfunctional Interaction) and the PSI-4 total score did not contribute significantly to the models. None of the four regression models on perceived quality of sleep were significant. It is important to note that 33% of parents responded defensively to the PSI-4. Conclusions: Parenting stress related to the child's behavioral problems and poor psychosocial adjustment, measured when the child is 4 months old, is associated with the child's ulterior anxiety symptoms. As very few standardized tools are available to assess the behavioral and psychoaffective development of infants, this study highlights the importance of early psychosocial screening in parents of infants with CHD. The high rate of significant Defensive Responding Indices reminds us to not take parent reports at face value, as their actual stress levels might be higher.

word count: 213 Statement of Significance word count: 116 Abstract Study objectives: Although sleepwalking (somnambulism) affects up to 4% of adults, its pathophysiology remains poorly understood. Sleepwalking can be preceded by fluctuations in slow-wave sleep EEG signals, but the significance of these pre-episode changes remains unknown and methods based on EEG functional connectivity have yet to be used to better comprehend the disorder.

The present study assessed brain perfusion patterns with single-photon emission computed tomography (SPECT) during sleepwalkers&#39; post-sleep deprivation slow-wave sleep (SWS) and resting-state wakefulness. Following a 24 hr period of sleep deprivation, 10 sleepwalkers and 10 sex- and age-matched controls were scanned with a high-resolution SPECT scanner. Participants were injected with 99mTc-ethylene cysteinate dimer after 2 min of stable SWS within their first sleep cycle as well as during resting-state wakefulness, both after a subsequent 24 hr period of sleep deprivation. When compared with controls&#39; brain perfusion patterns during both SWS and resting-state wakefulness, sleepwalkers showed reduced regional cerebral perfusion in several bilateral frontal regions, including the superior frontal, middle frontal, and medial frontal gyri. Moreover, reduced regional cerebral perfusion was also found in sleepwalkers&#39; left postcentral gyrus, insula, and superior temporal gyru...