Le tempérament de l’enfant, les différences individuelles et les forces environnementales

L'auteur commente certaines découvertes récentes sur le tempérament qui mettent en évidence les différences de chaque enfant dès les premiers mois de vie. Il souligne l'importance pour les parents d'ajuster leurs attitudes à chacun de leurs enfants. Il discute aussi de la relation possible du tempérament avec la «vulnérabilité» de certains enfants. Pour plusieurs raisons, l'évolution des méthodes éducatives au Québec depuis 15 ans semble démontrer de la part des parents un relâchement des normes de discipline et d'exigences, en contrepartie cependant d'un accroissement bénéfique de la communication affective avec l'enfant. L'auteur commente enfin Fhypothèse selon laquelle cette laxité s'est installée aux dépens de la fraction d'enfants les plus vulnérables de notre société.The author comments on recent findings in relation to infant temperament, which have demonstrated differences in each child from the first months of life. He stresses the importance for parents to adjust their attitudes to each of their children. The possible association of temperament with the "vulnerability" of certain children is discussed. For several reasons, the evolution of educational methods in Quebec over the last 15 years seems to show a relaxation of discipline and expectation norms on the part of parents, as a counterpart to the beneficial increase in affective communication with the child. The author discusses the hypothesis that this laxness has established itself at the expense of the most vulnerable function of children in our society

Principal Components of Heritability for High Dimension Quantitative Traits and General Pedigrees

For many complex disorders, genetically relevant disease definition is still unclear. For this reason, researchers tend to collect large numbers of items related directly or indirectly to the disease diagnostic. Since the measured traits may not be all influenced by genetic factors, researchers are faced with the problem of choosing which traits or combinations of traits to consider in linkage analysis. To combine items, one can subject the data to a principal component analysis. However, when family date are collected, principal component analysis does not take family structure into account. In order to deal with these issues, Ott & Rabinowitz (1999) introduced the principal components of heritability (PCH), which capture the familial information across traits by calculating linear combinations of traits that maximize heritability. The calculation of the PCHs is based on the estimation of the genetic and the environmental components of variance. In the genetic context, the standard estimators of the variance components are Lange's maximum\ud likelihood estimators, which require complex numerical calculations. The objectives of this paper are the following: i) to review some standard strategies available in the literature to estimate variance components for unbalanced data in mixed models; ii) to propose an ANOVA method for a genetic random effect model to estimate the variance components, which can be applied to general pedigrees and high dimensional family data within the PCH framework; iii) to elucidate the connection between PCH analysis and Linear Discriminant Analysis. We use computer simulations to show that the proposed method has similar asymptotic properties as Lange's method when the number of traits is small, and we study the efficiency of our method when the number of traits is large. A data analysis involving schizophrenia and bipolar quantitative traits is finally presented to illustrate the PCH methodology

Uptrend in distress and psychiatric symptomatology in pregnant women during the coronavirus disease 2019 pandemic

Introduction: Prenatal maternal distress has a negative impact on the course of pregnancy, fetal development, offspring development, and later psychopathologies. The study aimed to determine the extent to which the coronavirus disease 2019 (COVID-19) pandemic may aggravate the prenatal distress and psychiatric symptomatology of pregnant women. Material and methods: Two cohorts of pregnant volunteer women were evaluated, one that was recruited before the COVID-19 pandemic (n = 496) through advertisements in prenatal clinics in Quebec, Canada, from April 2018 to March 2020; the other (n = 1258) was recruited online during the pandemic from 2 April to 13 April 2020. Prenatal distress and psychiatric symptomatology were measured with the Kessler Distress Scale (K10), Post-traumatic Checklist for DSM-5 (PCL-5), Dissociative Experiences Scale (DES-II), and Positive and Negative Affect Schedule (PANAS). Results: The 1754 pregnant women (Mage = 29.27, SD = 4.23) were between 4 and 41 gestational weeks (M = 24.80, SD = 9.42), were generally educated (91.3% had post-high-school training), and financially well-resourced (85.3% were above the low-income cut-off). A multivariate analysis of covariance controlling for age, gestational age, household income, education, and lifetime psychiatric disorders showed a large effect size (ES) in the difference between the two cohorts on psychiatric symptoms (Wilks’ λ = 0.68, F6,1400 = 108.50, P <.001, partial η2 = 0.32). According to post-hoc analyses of covariance, the COVID-19 women reported higher levels of depressive and anxiety symptoms (ES = 0.57), dissociative symptoms (ES = 0.22 and ES = 0.25), symptoms of post-traumatic stress disorder (ES = 0.19), and negative affectivity (ES = 0.96), and less positive affectivity (ES = 0.95) than the pre-COVID-19 cohort. Women from the COVID-19 cohort were more likely than pre-COVID-19 women to present clinically significant levels of depressive and anxiety symptoms (OR = 1.94, χ2[1] = 10.05, P =.002). Multiple regression analyses indicated that pregnant women in the COVID-19 cohort having a previous psychiatric diagnosis or low income would be more prone to elevated distress and psychiatric symptoms. Conclusions: Pregnant women assessed during the COVID-19 pandemic reported more distress and psychiatric symptoms than pregnant women assessed before the pandemic, mainly in the form of depression and anxiety symptoms. Given the harmful consequences of prenatal distress on mothers and offspring, the presently observed upsurge of symptoms in pregnant women calls for special means of clinical surveillance. © 2020 Nordic Federation of Societies of Obstetrics and Gynecolog

Verbal and Visual Memory Impairments Among Young Offspring and Healthy Adult Relatives of Patients With Schizophrenia and Bipolar Disorder: Selective Generational Patterns Indicate Different Developmental Trajectories

Objective: Memory deficits have been shown in patients affected by schizophrenia (SZ) and bipolar (BP)/mood disorder. We recently reported that young high-risk offspring of an affected parent were impaired in both verbal episodic memory (VEM) and visual episodic memory (VisEM). Understanding better the trajectory of memory impairments from childhood to adult clinical status in risk populations is crucial for early detection and prevention. In multigenerational families densely affected by SZ or BP, our aim was to compare the memory impairments observed in young nonaffected offspring with memory functioning in nonaffected adult relatives and patients. Methods: For 20 years, we followed up numerous kindreds in the Eastern Québec population. After having characterized the Diagnostic and Statistical Manual of Mental Disorders phenotypes, we assessed cognition (N = 381) in 3 subsamples in these kindreds and in controls: 60 young offspring of a parent affected by SZ or BP, and in the adult generations, 92 nonaffected adult relatives and 40 patients affected by SZ or BP. VEM was assessed with the California Verbal Learning Test and VisEM with the Rey figures. Results: The VEM deficits observed in the offspring were also found in adult relatives and patients. In contrast, the VisEM impairments observed in the young offspring were present only in patients, not in the adult relatives. Conclusion: Implications for prevention and genetic mechanisms can be drawn from the observation that VEM and VisEM would show distinct generational trajectories and that the trajectory associated with VisEM may offer a better potential than VEM to predict future risk of developing the disease

Improving Theory of Mind in Schizophrenia by Targeting Cognition and Metacognition with Computerized Cognitive Remediation: A Multiple Case Study

Schizophrenia is associated with deficits in theory of mind (ToM) (i.e., the ability to infer the mental states of others) and cognition. Associations have often been reported between cognition and ToM, and ToM mediates the relationship between impaired cognition and impaired functioning in schizophrenia. Given that cognitive deficits could act as a limiting factor for ToM, this study investigated whether a cognitive remediation therapy (CRT) that targets nonsocial cognition and metacognition could improve ToM in schizophrenia. Four men with schizophrenia received CRT. Assessments of ToM, cognition, and metacognition were conducted at baseline and posttreatment as well as three months and 1 year later. Two patients reached a significant improvement in ToM immediately after treatment whereas at three months after treatment all four cases reached a significant improvement, which was maintained through 1 year after treatment for all three cases that remained in the study. Improvements in ToM were accompanied by significant improvements in the most severely impaired cognitive functions at baseline or by improvements in metacognition. This study establishes that a CRT program that does not explicitly target social abilities can improve ToM

Improving Theory of Mind in Schizophrenia by Targeting Cognition and Metacognition with Computerized Cognitive Remediation: A Multiple Case Study

Schizophrenia is associated with deficits in theory of mind (ToM) (i.e., the ability to infer the mental states of others) and cognition. Associations have often been reported between cognition and ToM, and ToM mediates the relationship between impaired cognition and impaired functioning in schizophrenia. Given that cognitive deficits could act as a limiting factor for ToM, this study investigated whether a cognitive remediation therapy (CRT) that targets nonsocial cognition and metacognition could improve ToM in schizophrenia. Four men with schizophrenia received CRT. Assessments of ToM, cognition, and metacognition were conducted at baseline and posttreatment as well as three months and 1 year later. Two patients reached a significant improvement in ToM immediately after treatment whereas at three months after treatment all four cases reached a significant improvement, which was maintained through 1 year after treatment for all three cases that remained in the study. Improvements in ToM were accompanied by significant improvements in the most severely impaired cognitive functions at baseline or by improvements in metacognition. This study establishes that a CRT program that does not explicitly target social abilities can improve ToM

Cognitive restructuring in the treatment of psychotic symptoms in schizophrenia : a critical analysis

This article reviews the 15 empirical studies that have used cognitive restructuring in the treatment of schizophrenia, more specifically for psychotic symptoms (delusions and hallucinations). Three elements are considered before investigating its effectiveness: (a) if subjects are reliably diagnosed with schizophrenia with chronic course and severe impairment; (b) if psychotic symptoms are adequately measured; and (c) if designs are methodologically sound. Our investigation revealed that schizophrenia is not reliably diagnosed and severity is low to moderate. Assessment of psychotic symptoms is satisfactory, but assessment of generalization to other areas is limited. Only five studies possess reliable design and are performed with schizophrenia subjects. These studies suggest that cognitive restructuring is effective to reduce or eliminate hallucinations or delusions in schizophrenia patients

Génétique de la schizophrénie et de la maladie bipolaire

Des résultats indiquant des liaisons sur deux chromosomes pour la schizophrénie (SZ) et la maladie bipolaire (BP) furent trop hâtivement rapportés dans la revue Nature à la fin des années 1980. Les connaissances accumulées à partir des insuccès de la première génération d’études génétiques moléculaires de la SZ et de la BP ont toutefois permis de jeter les bases de la seconde génération d’études de liaison, qui donnent maintenant des résultats convergents fort encourageants. Cet article présente une douzaine de sites génomiques de susceptibilité pour la SZ et la BP, certains d’entre eux étant probablement partagés par ces deux psychoses majeures, tandis que d’autres seraient spécifiques à chacune

Génétique de la schizophrénie et de la maladie bipolaire

Des résultats indiquant des liaisons sur deux chromosomes pour la schizophrénie (SZ) et la maladie bipolaire (BP) furent trop hâtivement rapportés dans la revue Nature à la fin des années 1980. Les connaissances accumulées à partir des insuccès de la première génération d’études génétiques moléculaires de la SZ et de la BP ont toutefois permis de jeter les bases de la seconde génération d’études de liaison, qui donnent maintenant des résultats convergents fort encourageants. Cet article présente une douzaine de sites génomiques de susceptibilité pour la SZ et la BP, certains d’entre eux étant probablement partagés par ces deux psychoses majeures, tandis que d’autres seraient spécifiques à chacune.Results claming linkage on two chromosomes for schizophrenia (SZ) and bipolar affective disorder (BP) were prematurely published in Nature at the end of the ‘80s. This ended up into disappointment. The knowledge accumulated from the first generation of unsuccessful molecular genetics studies of SZ and BP provided a stronger basis for the following generation of linkage studies that are now yielding encouraging converging results. Hence, we report several genomics susceptibility loci for SZ and BP, some of them being probably shared by the two major psychiatric illnesses whereas others could be specific to each

Polygenic risk scores distinguish patients from non-affected adult relatives and from normal controls in Schizophrenia and Bipolar Disorder multi-affected kindreds

Recent studies have used results on SNP association with schizophrenia (SZ) and bipolar disorder (BD) to create polygenic risk scores (PRS) discriminating non‐familial unrelated patients from controls. Little is known about the role of PRS in densely affected multigenerational families. We tested PRS differences between affected SZ and BD family members from their non‐affected adult relatives (NAARs) in Eastern Quebec Kindreds and from controls. We examined 1227 subjects: from 17 SZ and BD kindreds, we studied 153 patients (57 SZ, 13 schizoaffective, and 83 BD) and 180 NAARs, and 894 unrelated controls from the Eastern Quebec population. PRS were derived from published case‐control association studies of SZ and BD. We also constructed a combined SZ and BD PRS by using SNPs from both SZ and BD PRS. SZ patients had higher SZ PRS than controls (p = 0.0039, R2 = 0.027) and BD patients had higher BD PRS than controls (p = 0.013, R2 = 0.027). Differences between affected subjects and NAARs and controls were significant with both SZ and BD PRS. Moreover, a combined SZ‐BD PRS was also significantly associated with SZ and BD when compared to NAARs (p = 0.0019, R2 = 0.010) and controls (p = 0.0025, R2 = 0.028), revealing a SZ‐BD commonality effect in PRS at the diagnosis level. The SZ and the BD PRS, however, showed a degree of specificity regarding thought disorder symptoms. Overall, our report would confirm the usefulness of PRS in capturing the contribution of common genetic variants to the risk of SZ and BD in densely affected families