Some personality traits converge gradually by long-term partnership through the lifecourse – Genetic and environmental structure of Cloninger's temperament and character dimensions

Temperament and Character Inventory (TCI) is a comprehensive personality inventory that is widely used in behavioral genetics. The original theory suggested that temperament traits were under genetic influences, whereas character traits were gradually built by an interaction between temperaments and environment until early adulthood. This study attempted to evaluate TCI by examining the genetic and environmental contributions to personality with particular attention to spousal effects. From 687 families, a total of 3459 Korean adult individuals completed the survey. Among them, there were 542 Monozygotic (MZ) twin pairs and 122 Dizygotic twin pairs. Intraclass correlation coefficients (ICCs) and heritability were calculated to examine the genetic and shared environmental contributions to personality. Moderate genetic contributions (0.17–0.43) were found for all TCI traits along with the evidence of shared environment (0.11–0.31) for harm avoidance (HA) and all characters. The ICCs of TCI in MZ pairs ranged 0.36–0.46. Spouses' had little resemblance for temperament, whereas for character dimensions, spouses (0.27–0.38) were more similar than first degree relatives (0.10–0.29). Resemblance between spouses increased with duration of marriage for most characters and HA. When the growing similarities between spouses were compared with their MZ cotwins' for subgroup of 81 trios, self-directedness (SD) of character showed even more similarities toward their spouses than cotwins as partnership duration increased (r = 0.32). Our findings with regard to change in SD into late adulthood support the psychobiological theory of temperament and character, which suggests that both personality domains have distinct developmental trajectories despite equally large genetic influences.     

What is the effect of selective serotonin reuptake inhibitors on temperament and character in patients with fibromyalgia?

Objective

The purpose of the present study was to assess a group of patients with fibromyalgia (FM) and control subjects using the personality questionnaire proposed by Cloninger and to determine possible changes in the Italian version of the Temperament and Character Inventory—Revised patterns of patients with FM after therapy with serotoninergic antidepressants (selective serotonin reuptake inhibitors [SSRIs]).

Methods

Sixty patients with FM filled out the Temperament and Character Inventory—Revised and Beck Depression Inventory before and after 6-month therapy with SSRIs (escitalopram 10 mg, fluoxetine 20 mg, or paroxetine 20 mg). A total of 80 age-, sex-, and education level-matched healthy subjects were selected as a control group.

Results

Both in the pretreatment and posttreatment period, patients were found to have higher harm avoidance and lower self-directedness scores than healthy controls. In addition, harm avoidance and self-directedness were state and trait dependent.

Conclusions

Depressive symptoms in patients with FM can be significantly decreased by treatment with SSRIs. A careful clinical assessment and study of personality profile is needed to identify patients with FM who may benefit from antidepressant pharmacologic therapy and specific psychotherapeutic interventions.     

Do facets of self-reported impulsivity predict decision-making under ambiguity and risk? Evidence from a community sample

We investigated the links among decision-making assessed by the Iowa Gambling Task (IGT) and the Game of Dice Task (GDT), and the four facets of impulsivity (urgency, lack of premeditation, lack of perseverance, and sensation seeking, UPPS) proposed by Whiteside and Lynam (2001) in a sample of 107 healthy volunteers. Hierarchical regressions controlling for age and gender indicated that sensation seeking and urgency were linked to disadvantageous decisions on the GDT while no association was found between IGT performance and the UPPS. Sensation seeking and urgency facets of impulsivity are related in healthy individuals, to decision-making processes where potential consequences of different options and their subsequent probabilities rely on explicit information. In healthy controls, there is little overlap between decision-making influenced by both implicit and explicit information and impulsivity as measured by the UPPS. These findings add evidence to the notion that self-reported trait impulsivity is associated with the decision making process. Decisions made under risk seemed to be differentially associated with specific facets of impulsivity.     

Schizophrenia: do the genetics and neurobiology of neuregulin provide a pathogenesis model?

The sequencing of the human genome and an emerging dense map of markers across the human genome have spawned new approaches to search for risk genes for human diseases with complex genetics. These approaches are particularly relevant to the search for risk genes for bipolar disorder and schizophrenia. A gene called neuregulin 1 has been reported to be a risk gene for schizophrenia. This article reviews aspects of the genetics, cellular neurobiology, and biochemistry of neuregulin 1 and attempts to integrate several observations from disparate fields into a model for the pathogenesis of schizophrenia. The model outlines experimental approaches that may, in the future, shed more light on its validity.     

Do susceptibility loci contribute to the expression of more than one mental disorder? A view from the genetics of Alzheimer's disease

The susceptibility of developing most major psychiatric disorders is determined in part by contributions from risk alleles at multiple genetic loci. The central aim of this article is to highlight evidence from studies of neurodegenerative disorders suggesting that some of these alleles are shared by more than one psychiatric disorder, and to explore mechanisms that may underly these pleiotropic effects. The identification of constellations of susceptibility alleles associated with particular mental disorders will provide opportunities for new insights into the molecular and cellular pathophysiology of these disorders, and will have a major impact on psychiatric research and clinical care. This approach to reducing the variance in etiopathogenesis is also likely to be important for achieving the optimal use of available treatments (maximizing effectiveness and minimizing side effects), and for the discovery of novel medications or other interventions.     

Do gender and age moderate the symptom structure of PTSD? Findings from a national clinical sample of children and adolescents

A substantial body of evidence documents that the frequency and intensity of posttraumatic stress disorder (PTSD) symptoms are linked to such demographic variables as female sex (e.g., Kaplow et al., 2005) and age (e.g., Meiser-Stedman et al., 2008). Considerably less is known about relations between biological sex and age with PTSD's latent factor structure. This study systematically examined the roles that sex and age may play as candidate moderators of the full range of factor structure parameters of an empirically supported five-factor PTSD model (Elhai et al., 2011). The sample included 6591 trauma-exposed children and adolescents selected from the National Child Traumatic Stress Network's Core Data Set. Confirmatory factor analysis using invariance testing (Gregorich, 2006) and comparative fit index difference values (Cheung and Rensvold, 2002) reflected a mixed pattern of test item intercepts across age groups. The adolescent subsample produced lower residual error variances, reflecting less measurement error than the child subsample. Sex did not show a robust moderating effect. We conclude by discussing implications for clinical assessment, theory building, and future research.     

Do Low- and Middle-Income Countries Learn from the Experience of High-Income Countries?

An editorial posited that low- and middle-income countries (LMICs) take longer to access schizophrenia treatment innovations, but this lag may be an advantage in that that it allows them to have better evidence to inform clinical and policy decisions. We sought to determine whether LMIC policymakers do in fact use the best available evidence to make decisions regarding access to atypical antipsychotics, the latest innovation in schizophrenia therapeutics. Since there were no relevant policy analyses, we approached the issue by assessing the quality of the scientific evidence available to policymakers and examining in detail the experience of Chile, a middle-income country. We found that there is minimal LMIC-specific scientific evidence to inform policy analyses. Moreover, the modest body of cost-effectiveness evidence is undermined by the source of its effectiveness estimates. Only two of the four cost-effectiveness studies accounted for antipsychotics' side-effects, and only one included the long-term effects of metabolically active antipsychotics. LMICs that are able to manufacture or import cheaper generic atypical drugs have readily embraced them. Chile's experience indicates that an LMIC that implemented policies when evidence from higher-income countries strongly favored atypical drugs responded to new evidence to the contrary, but not forcefully enough to counter pressure from advocates or market forces. It appears, then, that most LMIC policymakers were not aware that the modest body of LMIC-relevant cost-effectiveness evidence did not favor atypicals, or if they were aware, their decisions were not influenced by this evidence. We conclude with a discussion of the implications of this finding.     

Do Drinking Motives and Drinking Contexts Mediate the Relationship Between Social Avoidance and Alcohol Problems? Evidence from Two Studies of Undergraduate Drinkers

Research suggests drinking motives and drinking context mediate the relation between social anxiety and alcohol problems. Study 1 examined coping with anxiety motives (CAM) and coping with depression motives (CDM) as distinct mediators in a self-report cross-sectional study of 263 undergraduate drinkers. CDM mediated the relation between social avoidance and alcohol problems (indirect effect = 0.07). Study 2 included drinking contexts and motives as mediators in a single model and included an additional coping with social anxiety drinking motive (CSAM) mediator in a self-report cross-sectional study of 189 undergraduate drinkers. Undergraduates with high levels of social avoidance drank for both CDM and CSAM, which in turn predicted heavy drinking in risky contexts (indirect effects = 0.09–0.16); however, drinking motives, rather than risky contexts, largely mediated the relation of social avoidance to alcohol problems (indirect effects = 0.08–0.14). Taken together, these results suggest that CDM and CSAM independently mediate the relationship between social avoidance and alcohol problems and might serve as useful intervention targets.

     

Are genetic factors important in the aetiology of leukoaraiosis? Results from a memory clinic population

Objective. To discover whether polymorphism in either the apolipoprotein E (ApoE) or angiotensin-converting enzyme (ACE) genes is associated with leukoaraiosis, white matter lesions visible on neuroimaging of the brain, which is commonly seen in dementia as well as some normal elderly subjects. Design. Prospective study of consecutive patients attending our memory disorders clinic, to examine the relationship between leukoaraiosis and polymorphism of the ApoE and ACE genes. Setting. Memory disorders clinic in Bristol, UK. Patients. 182 patients attending the memory disorders clinic for investigation of possible dementia of whom 75% were suffering from dementia, 20% from memory impairment but no dementia and in 5% of whom a dementing illness was thought to be unlikely; 38% of all patients had visible white matter lesions and 16% had cerebral infarcts. Measures. Patients and/or carers who agreed to participate in the study had their ACE and ApoE genotype determined and their brain CT/MRI scans were assessed by a neuroradiologist, blind to the result of the genotyping, for the presence or absence of white matter low attenuation. Results. There was a significant association between white matter lesions and the DD genotype (\mskip1 p\lt 0\dec 05), but not the ApoE genotype. However, this relationship with the DD genotype was only significant for patients with a previous infarct. Conclusion. Homozygosity of ACE gene deletion polymorphism is a risk factor for white matter lesions when it is associated with cerebral infarction. This suggests that it may be possible to identify subjects who are at greater risk of developing white matter lesions and are at risk of cognitive impairment and possibly dementia. © 1998 John Wiley & Sons, Ltd.     

Do Gaze Cues in Complex Scenes Capture and Direct the Attention of High Functioning Adolescents with ASD? Evidence from Eye-tracking

Visual fixation patterns whilst viewing complex photographic scenes containing one person were studied in 24 high-functioning adolescents with Autism Spectrum Disorders (ASD) and 24 matched typically developing adolescents. Over two different scene presentation durations both groups spent a large, strikingly similar proportion of their viewing time fixating the person’s face. However, time-course analyses revealed differences between groups in priorities of attention to the region of the face containing the eyes. It was also noted that although individuals with ASD were rapidly cued by the gaze direction of the person in the scene, this was not followed by an immediate increase in total fixation duration at the location of gaze, which was the case for typically developing individuals.     

Does COVID-19 increase the risk of neuropsychiatric sequelae? Evidence from a mendelian randomization approach

Observational studies based on electronic health records (EHR) report an increased risk of neurological/neuropsychiatric sequelae for patients who have had coronavirus disease 2019 (COVID-19). However, these studies may suffer from biases such as unmeasured confounding, residual reverse causality, or lack of precision in EHR-based diagnoses. To rule out these biases, we tested causal links between COVID-19 and different potential neurological/neuropsychiatric sequelae through a two-sample Mendelian randomization analysis of summary statistics from large Genome-Wide Association Scans of susceptibility to COVID-19 and different neurological and neuropsychiatric disorders, including major depression, anxiety, schizophrenia, stroke, Parkinson’s and Alzheimer’s diseases. We found robust evidence suggesting that COVID-19 – notably the hospitalized and most severe forms – carries an increased risk of neuropsychiatric sequelae, particularly Alzheimer’s disease, and to a lesser extent anxiety disorder. In line with a large longitudinal EHR-based study, this evidence was stronger for more severe COVID-19 forms. These results call for a targeted screening strategy to tackle the post-COVID neuropsychiatric pandemic.     

Do Faces Capture the Attention of Individuals with Williams Syndrome or Autism? Evidence from Tracking Eye Movements

The neuro-developmental disorders of Williams syndrome (WS) and autism can reveal key components of social cognition. Eye-tracking techniques were applied in two tasks exploring attention to pictures containing faces. Images were (i) scrambled pictures containing faces or (ii) pictures of scenes with embedded faces. Compared to individuals who were developing typically, participants with WS and autism showed atypicalities of gaze behaviour. Individuals with WS showed prolonged face gaze across tasks, relating to the typical WS social phenotype. Participants with autism exhibited reduced face gaze, linking to a lack of interest in socially relevant information. The findings are interpreted in terms of wider issues regarding socio-cognition and attention mechanisms.

Does cognitive status modify the relationship between education and mortality? Evidence from the Canadian Study of Health and Aging

BACKGROUND: There is compelling evidence of an inverse relationship between level of education and increased mortality. In contrast to this, one study showed that among subjects with Alzheimer's Disease, those with high education are more than twice as likely to die earlier; however, this result has proven difficult to replicate. We examine the relationship between education and mortality by cognitive status, using a large, nationally representative sample of elderly people. PATIENTS: A representative sample of 10,263 people, aged 65 or over, from the 10 Canadian provinces, participated in the Canadian Study of Health and Aging in 1991. METHODS: Information about age, gender, education, and an initial screening for cognitive impairment were collected; those who screened positive for cognitive impairment were referred for a complete clinical and neuropsychological examination, from which cognitive status and clinical severity of dementia were assessed. Vital status and date of death were collected at follow-up in 1996. The analysis was conducted using survival analysis. RESULTS: Cognitive status modifies the relationship between education and mortality. For those with no cognitive impairment, an inverse relationship between education and mortality exists. Elderly people with cognitive impairment but no dementia, or those with dementia, are more likely to die early than the cognitively normal at baseline, but no relationship exists between education and mortality. INTERPRETATION: These findings do not support previous work that showed a higher risk of mortality among highly educated dementia subjects.     

When and how do listeners relate a sentence to the wider discourse? Evidence from the N400 effect

In two ERP experiments, we assessed the impact of discourse-level information on the processing of an unfolding spoken sentence. Subjects listened to sentences like Jane told her brother that he was exceptionally quick/slow, designed such that the alternative critical words were equally acceptable within the local sentence context. In Experiment 1, these sentences were embedded in a discourse that rendered one of the critical words anomalous (e.g. because Jane's brother had in fact done something very quickly). Relative to the coherent alternative, these discourse-anomalous words elicited a standard N400 effect that started at 150-200 ms after acoustic word onset. Furthermore, when the same sentences were heard in isolation in Experiment 2, the N400 effect disappeared. The results demonstrate that our listeners related the unfolding spoken words to the wider discourse extremely rapidly, after having heard the first two or three phonemes only, and in many cases well before the end of the word. In addition, the identical nature of discourse- and sentence-dependent N400 effects suggests that from the perspective of the word-elicited comprehension process indexed by the N400, the interpretive context delineated by a single unfolding sentence and a larger discourse is functionally identical.     

Is the association between posttraumatic stress disorder symptoms and poor health due to a common familial or genetic factor?

OBJECTIVE: The objective of this study was to identify genetic, familial and environmental contributions to the association between posttraumatic stress disorder (PTSD) symptoms and poor health. METHODS: A community sample of 1852 twin pairs was assessed for symptoms of PTSD [with the Impact of Events Scale (IES)] and self-reported global health status using a single five-level question. An ordinal logistic regression model estimated odds ratio/s (OR) for the association between PTSD and health status. Within-pair analysis assessed confounding by familial and genetic factors and adjusted for the possible confounding influence of age, sex, race, education and self-reported physician diagnosis of depression. RESULTS: The IES was strongly and significantly associated with self-reported health [OR=1.8; 95% confidence interval (95% CI)=1.5-2.2; highest quartile vs. lowest quartile]. This association remained significant in within-pair analysis (OR=1.3; 95% CI=1.0-1.7), but after further adjustment for sociodemographics and depression, it was no longer significant (P(trend)=.17). Separate analysis by zygosity did not show differential effect in monozygotic or dizygotic pairs. CONCLUSION: These findings suggest that the association between PTSD symptoms and poor health is, in part, due to familial confounding and sociodemographic factors. Little evidence of confounding by genetic factors was found. These findings suggest that early prevention efforts would have the greatest potential for improving poor health in PTSD-prone patients, whereas later intervention efforts directed at treating PTSD may have a more limited impact on improving poor health.     

The impact of genetic and environmental factors on the pathobiology of Alzheimer's disease: a multifactorial disorder?

Summary

Alzheimer's disease is the most common form of dementia, although its diagnosis can only be confirmed after autopsy. While 10% of cases show a family history of the disease, the remainder are sporadic. Disease-causing mutations in three genes (amyloid precursor protein and two presenilin genes) have been discovered which account for nearly all of the familial cases of Alzheimer's disease. The sporadic forms of the disease are associated with a number of genetic risk factors (apolipoprotein E, x₁antichymotrypsin, very low density lipoprotein receptor and mitochondrial DNA mutations) but none of these are either sufficient on their own or necessary for the disease. This leaves open the possibility that one or more extrinsic environmental factors may affect the progression of Alzheimer's disease. Although the evidence for specific extrinsic factors is lacking, the role of putative agents (aluminium, antioxidants, head trauma) and how they might interact with intrinsic genetic factors is discussed. Alzheimer's disease, therefore, demonstrates genetic heterogeneity and, in addition, may be considered as a multifactorial disorder.