Dimensions of temperament as vulnerability factors in depression

Reinforcement-based responsiveness, depression, and anhedonia: A multi-method investigation of intergenerational risk

Offspring of depressed parents are at an increased risk for depression. Reward- and punishment-based systems might be mechanisms linking maternal outcomes to offspring depression and anhedonia. The current study was designed to investigate the intergenerational relations between maternal markers of reward and punishment responsiveness and their offspring's depression and anhedonia in a community sample of 40 mother (mean age = 44.5; SD = 6.82) and adolescent (mean age = 14.73; SD = 1.25; 52.5% female) dyads. Maternal markers of reward and punishment responsiveness were captured using self-report, behavioral, and neurophysiological methods, and self-reported depression and anhedonia symptoms were used as outcomes among the adolescent offspring. Maternal self-reported reward responsiveness and punishment learning rates were differentially associated with depression across male and female offspring. Regarding anhedonia, maternal punishment learning rate was positively related to adolescent anhedonia regardless of offspring biological sex. Maternal reward learning rate was also positively associated with anhedonia among male offspring. In general, low concurrence across self-report, behavioral, and neurophysiological markers of reward and punishment responsiveness was found. The results from the current study suggest that learning-rates on reinforcement-based behavioral tasks may be important objective markers to consider when evaluating intergenerational risk.

Comparison of the relative sensitivity of two dimensional personality models to the psychopathological symptoms: the section III DSM-5 maladaptive traits versus affective temperaments

BACKGROUND

The Personality Inventory for DSM-5 (PID-5) and Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Autoquestionnaire (TEMPS-A) are tools designed for personality dispositions for mental health symptoms. The present study was conducted to compare these models in terms of their relative sensitivity to the symptoms of personality disorders (PDs) and non-personality disorders (NPDs).

METHODS

Subjects in this cross-sectional study were 1232 (805 female; 63.5%) community samples in western Iran. Data were collected using the PID-5, the TEMPS-A, the Symptom Checklist-90 (SCL-90-R), and the Personality Diagnostic Questionnaire (PDQ-4). Correlations and Regression models were used to examine associations between traits and symptoms.

RESULTS

Maladaptive traits assessed by the PID-5 were more strongly associated with PD symptoms, whereas affective temperaments measured by the TEMPS-A were more strongly associated with NPD symptoms.

CONCLUSION

The present findings highlighted the practical utility of both the PID-5 and TEMPS-A indicating risk for psychopathology, but also suggest a distinction between PDs and NPDs in terms of underlying personality dispositions.

Association Between Step Count Measured With a Smartphone App (Pain-Note) and Pain Level in Patients With Chronic Pain: Observational Study

Background

Chronic pain is the leading cause of disability, affecting between 20% and 50% of the global population. The key recommended treatment is physical activity, which can be measured in daily life using a pedometer. However, poor adherence to pedometer use can result in incorrect measurements. Furthermore, only a few studies have investigated a possible curvilinear association between physical activity and chronic pain.

Objective

In this study, we developed the Pain-Note smartphone app to collect real-world data on step count, using the smartphone’s built-in pedometer. The aims of our research are (1) to evaluate the association between daily step count and pain level among patients with chronic pain and (2) determine if the association between daily step count and pain level was curvilinear.

Methods

We conducted a cross-sectional study based on step count data collected with the app and on the results of questionnaires, which measured the duration and intensity of pain, the widespread pain index, the symptom severity score, and the insomnia severity scale, including 7 questions for symptoms of depression. We analyzed the association between step count and pain level as a nonlinear relationship using a restricted cubic spline model. A prespecified subgroup analysis was also conducted based on fibromyalgia criteria.

Results

Between June 1, 2018, and June 11, 2020, a total of 6138 records were identified, of which 1273 were analyzed. The mean age of the participants was 38.7 years, 81.9% (1043/1273) were female, and chronic pain was present for more than 5 years in 43.2% (550/1273) of participants. Participants in the third and fourth quartiles for step count (more than 3045 and 5668 steps a day, respectively) showed a significant positive association between higher step count and lower numerical pain rating scale (mean difference –0.43, 95% CI –0.78 to –0.08, P=.02; –0.45; 95% CI –0.8 to –0.1, P=.01, respectively) than those in the first quartile (less than or equal to 1199 steps a day). The restricted cubic spline model for the association between step count and pain scale displayed a steep decline followed by a moderate decrease as the step count increased; the inflection point was 5000 steps. However, this association was not observed among participants who met the fibromyalgia criteria (491/1273), who showed a steep positive increase below 2000 steps. Data were collected between June 1, 2018, and June 11, 2020, and were analyzed on November 18, 2021.

Conclusions

Step count measured with the Pain-Note app showed a nonlinear association with pain level. Although participants with and without fibromyalgia showed a negative correlation between step count and pain level, participants who meet the criteria for fibromyalgia may present a different relationship between walking and pain perception compared to those in the general chronic pain population.

Etiological pathways of depressive and anxiety symptoms linked to personality traits: A genetically-informative longitudinal study

BACKGROUND

The comorbidity of depression and anxiety is associated with an increased risk of prolonged adverse mental health status. However, little is currently known about their genetic and environmental influences that help to explain both the comorbidity and distinctiveness. Using longitudinal twin data, the present study investigated both the overlapping and distinct relationships between depression and anxiety viewed from the perspective of Gray's Reinforcement Sensitivity Theory (RST): two personality traits of the Behavioral Inhibition and Activation Systems (BIS and BAS).

METHODS

A total of 422 twin pairs (298 monozygotic and 124 dizygotic pairs) participated by completing a personality questionnaire at wave 1, and mood symptoms questionnaires at wave 2. The waves were on average 2.23 years apart.

RESULTS

Multivariate Cholesky decomposition indicated that the genetic variance of the personality traits (BIS and BAS) explained all of the genetic variance in depressive and anxiety symptoms. Additionally, genetic factors related to the BIS positively explained depressive and anxiety symptoms, whereas genetic factors related to the BAS negatively explained only depressive symptoms.

LIMITATIONS

Limitations include shorter time interval and the reliance on self-reported data.

CONCLUSIONS

The present study provided evidence explaining the overlap and differentiation of depressive and anxiety symptoms by using data on personality traits in a longitudinal, genetically-informative design. The findings suggested the personality traits from Gray's RST model played an important role in the prediction, and clarified the description, of both depressive and anxiety symptoms.

Modeling heritability of temperamental differences, stress reactivity, and risk for anxiety and depression: Relevance to research domain criteria (RDoC)

Animal models provide important tools to study biological and environmental factors that shape brain function and behavior. These models can be effectively leveraged by drawing on concepts from the National Institute of Mental Health Research Domain Criteria (RDoC) Initiative, which aims to delineate molecular pathways and neural circuits that underpin behavioral anomalies that transcend psychiatric conditions. To study factors that contribute to individual differences in emotionality and stress reactivity, our laboratory utilized Sprague-Dawley rats that were selectively bred for differences in novelty exploration. Selective breeding for low versus high locomotor response to novelty produced rat lines that differ in behavioral domains relevant to anxiety and depression, particularly the RDoC Negative Valence domains, including acute threat, potential threat, and loss. Bred Low Novelty Responder (LR) rats, relative to their High Responder (HR) counterparts, display high levels of behavioral inhibition, conditioned and unconditioned fear, avoidance, passive stress coping, anhedonia, and psychomotor retardation. The HR/LR traits are heritable, emerge in the first weeks of life, and appear to be driven by alterations in the developing amygdala and hippocampus. Epigenomic and transcriptomic profiling in the developing and adult HR/LR brain suggest that DNA methylation and microRNAs, as well as differences in monoaminergic transmission (dopamine and serotonin in particular), contribute to their distinct behavioral phenotypes. This work exemplifies ways that animal models such as the HR/LR rats can be effectively used to study neural and molecular factors driving emotional behavior, which may pave the way toward improved understanding the neurobiological mechanisms involved in emotional disorders.

Temperamental factors in remitted depression: The role of effortful control and attentional mechanisms

BACKGROUND

Temperamental effortful control and attentional networks are increasingly viewed as important underlying processes in depression and anxiety. However, it is still unknown whether these factors facilitate depressive and anxiety symptoms in the general population and, more specifically, in remitted depressed individuals.

METHODS

We investigated to what extent effortful control and attentional networks (i.e., Attention Network Task) explain concurrent depressive and anxious symptoms in healthy individuals (n = 270) and remitted depressed individuals (n = 90). Both samples were highly representative of the US population.

RESULTS

Increased effortful control predicted a substantial decrease in symptoms of both depression and anxiety in the whole sample, whereas decreased efficiency of executive attention predicted a modest increase in depressive symptoms. Remitted depressed individuals did not show less effortful control nor less efficient attentional networks than healthy individuals. Moreover, clinical status did not moderate the relationship between temperamental factors and either depressive or anxiety symptoms.

LIMITATIONS

Limitations include the cross-sectional nature of the study.

CONCLUSIONS

Our study shows that temperamental effortful control represents an important transdiagnostic process for depressive and anxiety symptoms in adults.

Temperament and Character Traits Associated with Health-Related Quality of Life in Cancer Patients

Background

There is an increase in the attention to factors influencing the quality of life of cancer patients. The aim of the present study was to evaluate temperament and character traits related to health-related quality of life (HRQoL) in patients with cancer.

Methods

Two hundred and three inpatients from three Italian oncology departments filled in the Temperament Character Inventory (TCI-140) based on Cloninger's personality model, the SF-36 questionnaire assessing HRQoL, and the Hospital Anxiety and Depression Scale (HADS). Eighty percent of patients were undergoing chemotherapy.

Results

Lower levels of harm avoidance and higher levels of self-directedness were significantly correlated with a better HRQoL. Regression analysis controlling for psychopathology (anxiety and depression symptoms) showed that the influence of temperament and character traits on quality of life seemed to add little to the influence of psychopathology.

Conclusions

The present study demonstrates the existence of some relations between HRQoL and temperament and character traits assessed using the TCI-140 questionnaire. However, among the psychological factors, psychopathology seems to retain more influence on HRQoL of cancer patients.

Characteristics of depressive patients according to family history of affective illness: Findings from a French national cohort

BACKGROUND

Literature is scarce about the characteristics of mood disorder patients with a family history (FH) of affective illness. The aim of the current study was to compare the prominent features of depressive patients with a FH of mania (FHM), those of depressive patients with a FH of depression (FHD), and those of depressive patients with no FH of affective illness (FHO).

METHODS

As part of the EPIDEP National Multisite French Study of 493 consecutive DSM-IV major depressive patients evaluated in at least two semi-structured interviews 1 month apart, 45 (9.1%) were classified as FHM, 210 (42.6%) as FHD, and 238 (48.3%) as FHO.

RESULTS

The main characteristics of FHM patients were a cyclothymic temperament, the presence of mixed features and diurnal variations of mood during depression, early sexual behaviour, a high number of mood episodes and hypomanic switches, high rates of suicide attempts and rapid cycling; diagnosis of bipolar disorder was more frequent in this group as well as comorbid obsessive compulsive disorder, posttraumatic stress disorder, bulimia, attention deficit/hyperactivity disorder and impulse control disorders. The FHD patients had more depressive temperament, generalized anxiety disorder, and anorexia nervosa. Compared to FHO, FHM and FHD showed an earlier age at onset, more comorbid anxiety disorders, as well as more psychotic features.

LIMITATIONS

The following are the limitations of this study: retrospective design, recall bias, and preferential enrolment of bipolar patients with a depressive predominant polarity.

CONCLUSIONS

In light of genetic studies conducted in affective disorder patients, our findings may support the hypothesis of genetic risks factors common to affective disorders and dimensions of temperament, that may extend to comorbid conditions specifically associated with bipolar or unipolar illness.

Neuropsychological performance and affective temperaments in Euthymic patients with bipolar disorder type II

Affective temperament has been suggested as a potential mediator of the effect between genetic predisposition and neurocognitive functioning. As such, this report seeks to assess the extent of the correlation between affective temperament and cognitive function in a group of bipolar II subjects. 46 bipolar II outpatients [mean age 41.4 years (SD 18.2); female 58.9%] and 46 healthy controls [mean age 35.1 years (SD 18); female 56.5%] were evaluated with regard to their demographic and clinical characteristics, affective temperament, and neurocognitive performance. Crude bivariate correlation analyses and multiple linear regression models were constructed between five affective temperament subscales and eight neurocognitive domains. Significant correlations were identified in bipolar patients between hyperthymic temperament and verbal memory and premorbid IQ; cyclothymic temperament and attention; and irritable temperament, attention, and verbal fluency. In adjusting for potential confounders of the relationship between temperament and cognitive function, the strongest mediating factors among the euthymic bipolar patients were found to be residual manic and depressive symptoms. It is therefore concluded that affective temperaments may partially influence the neurocognitive performance of both healthy controls and euthymic patients with bipolar disorder type II in several specific domains.

Treatment-resistant depression: are animal models of depression fit for purpose?

BACKGROUND

Resistance to antidepressant drug treatment remains a major health problem. Animal models of depression are efficient in detecting effective treatments but have done little to increase the reach of antidepressant drugs. This may be because most animal models of depression target the reversal of stress-induced behavioural change, whereas treatment-resistant depression is typically associated with risk factors that predispose to the precipitation of depressive episodes by relatively low levels of stress. Therefore, the search for treatments for resistant depression may require models that incorporate predisposing factors leading to heightened stress responsiveness.

METHOD

Using a diathesis-stress framework, we review developmental, genetic and genomic models against four criteria: (i) increased sensitivity to stress precipitation of a depressive behavioural phenotype, (ii) resistance to chronic treatment with conventional antidepressants, (iii) a good response to novel modes of antidepressant treatment (e.g. ketamine; deep brain stimulation) that are reported to be effective in treatment-resistant depression and (iv) a parallel to a known clinical risk factor.

RESULTS

We identify 18 models that may have some potential. All require further validation. Currently, the most promising are the Wistar-Kyoto (WKY) and congenital learned helplessness (cLH) rat strains, the high anxiety behaviour (HAB) mouse strain and the CB1 receptor knockout and OCT2 null mutant mouse strains.

CONCLUSION

Further development is needed to validate models of antidepressant resistance that are fit for purpose. The criteria used in this review may provide a helpful framework to guide research in this area.

Individual differences in response to positive and negative stimuli: endocannabinoid-based insight on approach and avoidance behaviors

Approach and avoidance behaviors-the primary responses to the environmental stimuli of danger, novelty and reward-are associated with the brain structures that mediate cognitive functionality, reward sensitivity and emotional expression. Individual differences in approach and avoidance behaviors are modulated by the functioning of amygdaloid-hypothalamic-striatal and striatal-cerebellar networks implicated in action and reaction to salient stimuli. The nodes of these networks are strongly interconnected and by acting on them the endocannabinoid and dopaminergic systems increase the intensity of appetitive or defensive motivation. This review analyzes the approach and avoidance behaviors in humans and rodents, addresses neurobiological and neurochemical aspects of these behaviors, and proposes a possible synaptic plasticity mechanism, related to endocannabinoid-dependent long-term potentiation (LTP) and depression that allows responding to salient positive and negative stimuli.

Developmental trajectories of anxious and depressive problems during the transition from childhood to adolescence: personality × parenting interactions

This study examined separate developmental trajectories of anxious and depressive symptoms from childhood to adolescence (9-15 years) in a community-based sample (N = 290). At three measurement points, mothers and fathers reported on their children's anxious and depressive symptoms, and at Time 1 they reported on lower order child personality facets and on their parenting. By means of growth mixture modeling, three developmental trajectories were identified for anxious symptoms: steady low (82%), moderate increasing-decreasing (5.9%), and high declining groups (12.1%). For depressive symptoms, two developmental trajectories were found: steady low (94.1%) and moderate increasing groups (5.9%). Higher shyness, irritability, and altruism predicted membership in more problematic anxious and depressive groups. The personality facets energy, optimism, compliance, and anxiety were unique predictors for class membership for anxious symptoms, and the effects of shyness, irritability, and compliance were moderated by overreactive parenting. Shyness and irritability increased the probability of following the moderate increasing-decreasing anxiety trajectory, but only in the context of high or average levels of overreactive parenting. Compliance increased the probability of following the moderate increasing-decreasing and high decreasing trajectories in the context of high overreactive parenting. Our results indicate that childhood personality facets differentiate trajectories of anxious and depressive symptoms in theoretically compelling ways.

Oxytocin's role in anxiety: a critical appraisal

A growing literature suggests that the oxytocin (OT) system may play a role in human anxiety states, anxiety-related traits, and moreover, that this system may be a target for the development of novel anxiolytic treatments. However, studies of OT's acute and chronic effects on various aspects of anxiety have produced mixed results. In this forward-looking review, we discuss the myriad phenomena to which the term "anxiety" is applied in the OT literature and the problem this presents developing a coherent picture of OT's role in anxiety. We then survey several different fields of research that support the role of the OT system in human anxiety, including evolutionary perspectives, translational and neuroimaging research, genetic studies, and clinical trials of intranasal OT. As an outgrowth of this data, we propose a "bowtie" model of OT's role at the interface of social attachment and anxiety. We next direct attention to understudied brain regions and neural circuits which may be important to study in OT experiments in humans anxiety disorders. Finally, we conclude by proposing questions and priorities for studying both the clinical potential of OT in anxiety, as well as mechanisms that may underlie this potential. Crucially, these priorities include targeted proof-of-concept clinical trials of IN OT in certain anxiety disorders, including investigations of individual moderators of OT's anxiolytic effects (i.e. sex, genetic factors, and early experience). This article is part of a Special Issue entitled Oxytocin and Social Behav.

Two Cohort and Three Independent Anonymous Twin Projects at the Keio Twin Research Center (KoTReC)

The Keio Twin Research Center has conducted two longitudinal twin cohort projects and has collected three independent and anonymous twin data sets for studies of phenotypes related to psychological, socio-economic, and mental health factors. The Keio Twin Study has examined adolescent and adult cohorts, with a total of over 2,400 pairs of twins and their parents. DNA samples are available for approximately 600 of these twin pairs. The Tokyo Twin Cohort Project has followed a total of 1,600 twin pairs from infancy to early childhood. The large-scale cross-sectional twin study (CROSS) has collected data from over 4,000 twin pairs, from 3 to 26 years of age, and from two high school twin cohorts containing a total of 1,000 pairs of twins. These data sets of anonymous twin studies have mainly targeted academic performance, attitude, and social environment. The present article introduces the research designs and major findings of our center, such as genetic structures of cognitive abilities, personality traits, and academic performances, developmental effects of genes and environment on attitude, socio-cognitive ability and parenting, genes x environment interaction on attitude and conduct problem, and statistical methodological challenges and so on. We discuss the challenges in conducting twin research in Japan.

[Psychotherapeutic and psychosocial interventions and endophenotypes in bipolar disorders]

Diseases with complex determinism, bipolar disorders, involve at the same time environmental and genetic factors of vulnerability. The characterization of these vulnerabilities would allow a better knowledge of their etiology and envisage the development of therapeutics, more specialized, even preventive. The research in genetic psychiatry allowed to highlight endophenotype candidates associated to bipolar disorders. They are endogenous clinical or biological features, biologically more elementary than phenotypes and more directly bound to the physiological consequences of genes and their polymorphisms. Targeting some of them with specific psychotherapy and psychosocial interventions could reduce the consequences of their expression and so have an action on the course of the disease and also preventive.

Linking novelty seeking and harm avoidance personality traits to cerebellar volumes

Personality traits are multidimensional traits comprising cognitive, emotional, and behavioral characteristics, and a wide array of cerebral structures mediate individual variability. Differences in personality traits covary with brain morphometry in specific brain regions, and neuroimaging studies showed structural or functional abnormalities of cerebellum in subjects with personality disorders, suggesting a cerebellar role in affective processing and an effect on personality characteristics. To test the hypothesis that cerebellar [white matter (WM) and cortex] volumes are correlated with scores obtained in the four temperamental scales of the Temperament and Character Inventory (TCI) by Cloninger, a total of 125 healthy participants aged 18-67 years of both genders (males = 52) completed the TCI and underwent magnetic resonance imaging. The scores obtained in each temperamental scale were associated with the volumes of cerebellar WM and cortex of right and left hemispheres separately by using linear regression analyses. In line with our hypothesis, novelty seeking (NS) scores were positively associated with WM and cortex cerebellar volumes. Harm avoidance (HA) scores were negatively associated with WM and cortex cerebellar volumes. The range of individual differences in NS and HA scores reflects the range of variances of cerebellar volumes. The present data indicating a cerebellar substrate for some personality traits extend the relationship between personality and brain areas to a structure up to now thought to be involved mainly in motor and cognitive functions, much less in emotional processes and even less in personality individual differences.

Trait impulsivity as an endophenotype for bipolar I disorder

OBJECTIVE

Impulsivity, conceptualized as impairment in planning and poor attentional and inhibitory control, is a key feature of bipolar disorder. Familial risk for bipolar disorder is known to affect inhibitory control but its impact on the attentional and planning dimensions of impulsivity is still unclear.

METHODS

We administered the Barratt Impulsiveness Scale, version 11 (BIS-11) to 54 euthymic individuals with DSM-IV bipolar I disorder, 57 of their clinically unaffected siblings, and 49 healthy comparison subjects. Groups were compared on the attentional (rapid shifts in attention/impatience with complexity), motor (acting impetuously), and non-planning (absence of weighing upon long-term consequences of actions) subscales of the BIS-11, and on total BIS-11 score. To investigate functional implications of trait impulsivity, total BIS-11 score was examined in relation to current psychosocial functioning and criminal history.

RESULTS

Individuals with bipolar I disorder had elevated scores compared to healthy comparison subjects on BIS-11 total score and all three subscales (p < 0.0001). Unaffected siblings had elevated BIS-11 total score (p = 0.0037), motor (p = 0.0027), and non-planning (p = 0.0379) subscales in comparison to unrelated healthy controls. Total BIS-11 score was negatively associated with global assessment of functioning (GAF) score (β = -0.32, p < 0.0001).

CONCLUSIONS

 Our results suggest that impulsivity is sensitive to familial liability for the illness, making it a potential endophenotype for bipolar disorder.

A genome-wide meta-analysis of association studies of Cloninger's Temperament Scales

Temperament has a strongly heritable component, yet multiple independent genome-wide studies have failed to identify significant genetic associations. We have assembled the largest sample to date of persons with genome-wide genotype data, who have been assessed with Cloninger's Temperament and Character Inventory. Sum scores for novelty seeking, harm avoidance, reward dependence and persistence have been measured in over 11,000 persons collected in four different cohorts. Our study had >80% power to identify genome-wide significant loci (P<1.25 × 10(-8), with correction for testing four scales) accounting for ≥0.4% of the phenotypic variance in temperament scales. Using meta-analysis techniques, gene-based tests and pathway analysis we have tested over 1.2 million single-nucleotide polymorphisms (SNPs) for association to each of the four temperament dimensions. We did not discover any SNPs, genes, or pathways to be significantly related to the four temperament dimensions, after correcting for multiple testing. Less than 1% of the variability in any temperament dimension appears to be accounted for by a risk score derived from the SNPs showing strongest association to the temperament dimensions. Elucidation of genetic loci significantly influencing temperament and personality will require potentially very large samples, and/or a more refined phenotype. Item response theory methodology may be a way to incorporate data from cohorts assessed with multiple personality instruments, and might be a method by which a large sample of a more refined phenotype could be acquired.

Registry of Adolescent and Young Adult Twins in the Tokyo Area

Since established in 1998, the Keio Twin Project (KTP) has been dedicated to investigating genetic and environmental sources contributing to human psychological traits in adolescence and young adulthood. A population-based twin registry was constructed by the KTP through the use of official residential records in the Tokyo area, and to date requests to participate in our research have generated 1040 pairs of twins and triplets of age 14 to 30, forming one of the largest twin registries in Asia. Our comprehensive datasets, obtained through questionnaires, performance tests, and physical measurements, cover a wide range of human traits: personality, psychiatry, mental health, sociality, cognition, and physical index. Demographic variables and environment of upbringing are also sought by twins and by some parents. This extensive information allows us to clarify the genetic and environmental overlap across multiple traits as well as specificities unique to single traits. Adding an evolutionary psychology perspective to the behavior genetics framework is currently being attempted in order to develop a grand theory of human genetics.

Personality traits in patients with Parkinson's disease: assessment and clinical implications

This study reviews empirical evidence on the association between personality traits and Parkinson's disease (PD), with a twofold aim. First, to better identify non-motor symptoms, such as affective symptoms and personality changes, that could help to define the pre-motor phase of PD; second, to better understand the neurobiological bases of personality traits, a goal that is not fully accomplished by a purely anatomical approach. A literature review was performed on studies of personality traits in PD patients, in electronic databases ISI Web of Knowledge, Medline and PsychInfo, conducted in July 2011. We found evidence that the existence of a characteristic premorbid personality profile of PD patients is not actually sustained by robust empirical evidence, mainly due to the methodological bias of the retrospective assessment of personality; PD patients present a personality profile of low novelty seeking and high harm avoidance. We concluded that the definition of a pre-motor phase of PD, based on non-motor symptoms, should search for the presence of concomitant affective disorders and for a positive psychiatric history for affective disorders rather than for a typical personality profile or personality changes. The low novelty seeking profile is probably related to the dopaminergic deficit, while the high harm avoidance profile is probably associated with the presence of affective disorders. Clinical implications of these findings, in regard to personality assessment and pharmacological treatments in PD, are also discussed.

Negative affectivity, self-referential processing and the cortical midline structures

The neural bases of the association between negative affectivity and self-focus remain unknown in healthy subjects. Building on the role of the cortical midline structures (CMS) in self-referential processing, we hypothesized that negative affectivity in healthy subjects would be associated with an increased activation of the CMS during self-referential processing. We presented positive and negative pictures to 45 healthy subjects during fMRI and asked them to judge whether the pictures were related to themselves or not (self condition), or whether the pictures were positive or negative (general condition). Negative affectivity was measured by the level of harm avoidance (HA) with the Temperament and Character Inventory. Self-referential processing activated the CMS, including the dorsal and ventral medial prefrontal cortex (MPFC) and the posterior cingulate cortex (PCC). A higher HA score was associated with a greater activation of the dorsal MPFC and PCC during self-referential processing, this greater activation being more pronounced for negative pictures in the dorsal MPFC. This increased activation of the CMS may embody the association between negative affectivity and self-focus in healthy subjects, as previously observed in major depression. Within the CMS, the dorsal MPFC may play a key role in negative affectivity, integrating an increased attention to negative stimuli with an increased attention to the self.

Temperament and character associated with depressive symptoms in women: analysis of two genetically informative samples

Although previous research has explored associations between personality and depressive symptoms, a limited number of studies have assessed the extent to which genetic and environmental influences explain the association. This study investigated how temperament and character were associated with depressive symptoms in 131 pairs of twin and sibling women in early adulthood, as well as 326 pairs of twin women in middle adulthood. Results indicated that genetic influences accounted for a moderate to substantial percentage of the association between these personality features and depressive symptoms, emphasizing the role of genetic influences. Nonshared environmental influences made important contributions to the association between character and depressive symptoms, particularly in the sample of middle-aged twin women. These findings suggest that unique social experiences and relationships with a partner in adulthood may play an important role in these associations between character and depressive symptoms.

Individual differences in personality traits reflect structural variance in specific brain regions

Personality dimensions such as novelty seeking (NS), harm avoidance (HA), reward dependence (RD) and persistence (PER) are said to be heritable, stable across time and dependent on genetic and neurobiological factors. Recently a better understanding of the relationship between personality traits and brain structures/systems has become possible due to advances in neuroimaging techniques. This Magnetic Resonance Imaging (MRI) study investigated if individual differences in these personality traits reflected structural variance in specific brain regions. A large sample of eighty five young adult participants completed the Three-dimensional Personality Questionnaire (TPQ) and had their brain imaged with MRI. A voxel-based correlation analysis was carried out between individuals' personality trait scores and grey matter volume values extracted from 3D brain scans. NS correlated positively with grey matter volume in frontal and posterior cingulate regions. HA showed a negative correlation with grey matter volume in orbito-frontal, occipital and parietal structures. RD was negatively correlated with grey matter volume in the caudate nucleus and in the rectal frontal gyrus. PER showed a positive correlation with grey matter volume in the precuneus, paracentral lobule and parahippocampal gyrus. These results indicate that individual differences in the main personality dimensions of NS, HA, RD and PER, may reflect structural variance in specific brain areas.

The heritability of hedonic capacity and perceived stress: a twin study evaluation of candidate depressive phenotypes

BACKGROUND

Anhedonia and stress sensitivity have been identified as promising depressive phenotypes. Research suggests that stress-induced anhedonia is a possible mechanism underlying the association between stress and depression. The present proof-of-concept study assessed whether hedonic capacity and stress perception are heritable and whether their genetic and environmental contributions are shared.

METHOD

Twenty monozygotic (MZ) and 15 dizygotic (DZ) twin pairs completed a probabilistic reward task that provides an objective behavioral measure of hedonic capacity (reward responsiveness) and completed several questionnaires including the Perceived Stress Scale (PSS). Bivariate Cholesky models were used to investigate whether covariation between (1) depressive symptoms and hedonic capacity, (2) depressive symptoms and perceived stress, and (3) perceived stress and hedonic capacity resulted from shared or residual genetic and environmental factors.

RESULTS

Additive genetic (A) and individual-specific environment (E) factors contributed to 46% and 54% of the variance in hedonic capacity, respectively. For perceived stress, 44% and 56% of the variance was accounted for by A and E factors, respectively. The genetic correlation between depression and hedonic capacity was moderate (ra=0.29), whereas the correlation between depression and stress perception was large (ra=0.67). Genetic and environmental correlations between hedonic capacity and stress perception were large (ra=0.72 and re=-0.43).

CONCLUSIONS

The present study provides initial feasibility for using a twin approach to investigate genetic contributions of a laboratory-based anhedonic phenotype. Although these preliminary findings indicate that hedonic capacity and perceived stress are heritable, with substantial shared additive genetic contributions, replications in larger samples will be needed.

Empirical Support for Resilience as More than the Counterpart and Absence of Vulnerability and Symptoms of Mental Disorder

The construct of resilience has been viewed as the direct counterpart of factors jeopardizing mental health, i.e., vulnerability and psychopathology. Any operationalization of resilience, thus, risks lying on the same latent continuum as indicators of mental illness, although indicating their absence. A factor analysis combining items from these measurement domains, followed by analyses of second-order factor scores was performed to test this assumption. A random selection of 1,724 participants (34% response rate) from the general population of Norway responded. All items were discriminated well by their primary factors. A second-order factor analysis extracted two components, which was confirmed on a hold-out sample by confirmatory factor methods. The Resilience Scale for Adults (RSA), which measures protective factors, correlated with both second-order factors. Thus, the RSA shared common variance with vulnerability and psychopathology, as well as being unique from illness indices. A hierarchical regression analysis that tested interactions between vulnerability and resilience further supported the unique contributions of the RSA. Thus, the notion of resilience-protective indicators as solely counterparts of vulnerability and psychopathology is not empirically supported.

The primacy of mania: a reconsideration of mood disorders

In contemporary psychiatry, depression and mania are conceived as different entities. They may occur together, as in bipolar disorder, or they may occur separately, as in unipolar depression. This view is partly based on a narrow definition of mania and a rather broad definition of depression. Generally, depression is seen as more prominent, common, and problematic; while mania appears uncommon and treatment-responsive. We suggest a reversal: mania viewed broadly, not as simply episodic euphoria plus hyperactivity, but a wide range of excitatory behaviors; and depression seen more narrowly. Further, using pharmacological and clinical evidence, and in contrast to previous theories of mania interpreted as a flight from depression, we propose the primacy of mania hypothesis (PM): depression is a consequence of the excitatory processes of mania. If correct, current treatment of depressive illness needs revision. Rather than directly lifting mood with antidepressants, the aim would be to suppress manic-like excitation, with depression being secondarily prevented. Potential objections to, and empirical tests of, the PM hypothesis are discussed.

Body size at birth and socio-economic status in childhood: implications for Cloninger's psychobiological model of temperament at age 60

Small birth size predicts various psychiatric outcomes, including depression. While biologically based temperamental traits may constitute a vulnerability factor for depression, the extent to which birth size predicts these traits in adulthood is not known. We studied, in 1369 women and men identified from a cohort born in 1934-44 in Helsinki, Finland, whether birth size predicts the temperamental traits measured with Cloninger's Tridimensional Personality Questionnaire at an average age of 63 years. Moreover, we examined whether socio-economic status (SES) in childhood modified the associations. Data on birth size were obtained from birth records, and SES in childhood was obtained from school records. Weight and length at birth showed curvilinear, reverse J-shaped effects on harm avoidance (HA), such that the highest HA scores were most characteristic of those born small. Furthermore, high HA was confined to those belonging to a low SES group in childhood regardless of birth size, and to those belonging to the high SES group in childhood if their birth size was small. The associations were independent of several confounders. Since small birth size as well as high HA in adulthood may associate with subsequent depression, our findings might shed light on understanding the early neurodevelopmental processes that predispose to depression through vulnerability characteristics.

Genetic variation in MAOA modulates ventromedial prefrontal circuitry mediating individual differences in human personality

Little is known about neural mechanisms underlying human personality and temperament, despite their considerable importance as highly heritable risk mediators for somatic and psychiatric disorders. To identify these circuits, we used a combined genetic and imaging approach focused on Monoamine Oxidase A (MAOA), encoding a key enzyme for monoamine metabolism previously associated with temperament and antisocial behavior. Male carriers of a low-expressing genetic variant exhibited dysregulated amygdala activation and increased functional coupling with ventromedial prefrontal cortex (vmPFC). Stronger coupling predicted increased harm avoidance and decreased reward dependence scores, suggesting that this circuitry mediates a part of the association of MAOA with these traits. We utilized path analysis to parse the effective connectivity within this system, and provide evidence that vmPFC regulates amygdala indirectly by influencing rostral cingulate cortex function. Our data implicate a neural circuit for variation in human personality under genetic control, provide an anatomically consistent mechanism for vmPFC-amygdala interactions underlying this variation, and suggest a role for vmPFC as a superordinate regulatory area for emotional arousal and social behavior.

Increased anxiety and other similarities in temperament of alcoholics with and without antisocial personality disorder across three diverse populations

According to Cloninger's model, type I alcoholics are thought to be innately vulnerable to anxiety and depression. In contrast, type II alcoholics are thought to have increased likelihood of antisocial personality disorder (ASPD) and reduced anxiety. However, allostatic activations of stress, anxiety, and dysphoria may be a common thread in alcohol use disorders (AUDs). Our aim was to find commonalities and differences in temperament of alcoholics with and without ASPD in three diverse populations. By sib-sib comparisons, we also evaluated the extent to which the temperament traits were moderated by familial factors including inheritance. We compared harm avoidance (HA), novelty seeking (NS), and reward dependence (RD) in alcoholics with ASPD, alcoholics without ASPD, and controls. Correlations for each temperament dimension were evaluated in pairs of siblings concordant and discordant for AUD. Participants were derived from three independent populations: Finnish Caucasians (N=453, men=100%, including a sample of alcoholic criminals), a Plains American Indian community sample (N=378; men=42%), and a subset of the familial and predominantly Caucasian Collaborative Study on the Genetics of Alcoholism (COGA) sample (N=967, men=47%). In all the three populations, both alcoholics with and without ASPD were higher in HA than controls. The increase of HA among alcoholics as compared to controls ranged from 54% to 12%. In two populations (COGA and Finns), NS was highest in alcoholics with ASPD, intermediate in alcoholics without ASPD, and lowest in controls. HA levels were correlated in sib-pairs concordant (either affected or unaffected) for AUD but not in discordant pairs. In conclusions, despite cultural diversity and different modes of ascertainment we found a consistent pattern of elevated HA in all groups of alcoholics, including alcoholics with ASPD. Even in alcoholics with long-term exposure to the anxiogenic effects of repeated cycles of alcohol withdrawal, genetic and other familial influences seem to play a role in moderating anxiety.

Twin studies in pediatric depression

Pediatric depression is an important clinical problem that is known to be familial. Twin studies have been used not only to examine the genetic etiology of depression but also to investigate developmental changes and gender effects, the relationship of depression with anxiety, and increasingly, the interplay of genetic liability with environmental risk factors. There is evidence that pediatric depression symptom scores and clinical depression are genetically influenced, but results from different twin studies have varied. These studies also have demonstrated the important contribution of environmental risk factors. Some of the differences in findings may be caused partly by clinical heterogeneity, developmental differences in etiology (stronger genetic influences for depression symptom scores in adolescence than in childhood), and measurement issues, such as who rates the symptoms.

Temperament and character in mood disorders: influence of DRD4, SERTPR, TPH and MAO-A polymorphisms

Gene variants exert a complex range of effects on human normal and abnormal behavior. We previously reported the effect of gene variants in serotoninergic and dopaminergic pathways, in a range of clinical features in mood disorders, such as symptomathology, periodicity, social adjustment and treatment response. In this paper we hypothesized that the same gene variants could influence temperamental traits in mood disorders patients. We focused on genes of the serotoninergic and dopaminergic systems (dopamine receptor D4 gene, DRD4; serotonin transporter gene, promoter region SERTPR; tryptophan hydroxylase gene, TPH; monoamine oxidase A gene, MAO-A). Two hundred and seven euthymic subjects, affected by major depressive disorder (n=73) and bipolar disorder (n=134) were assessed by the Cloninger's Temperament and Character Inventory (TCI) and typed using PCR-based analyses. Possible stratification factors such as demographic, clinical and other temperamental factors were also taken into account. We observed that homozygosity for the short SERTPR allele was associated with low novelty-seeking scores (p=0.006) and genotypes containing the DRD4 long allele were marginally associated with low harm avoidance (p=0.05). Finally, the long MAO-A allele was associated with decreased persistence scores among females (p=0.006). Our observation of a pattern of influence on temperamental dimension exerted by serotonergic and dopaminergic genes suggests that the contribution of these polymorphisms to the clinical presentation of mood disorders could be mediated by an influence on personality differences.

Common emotional and behavioral disorders in preschool children: presentation, nosology, and epidemiology

We review recent research on the presentation, nosology and epidemiology of behavioral and emotional psychiatric disorders in preschool children (children ages 2 through 5 years old), focusing on the five most common groups of childhood psychiatric disorders: attention deficit hyperactivity disorders, oppositional defiant and conduct disorders, anxiety disorders, and depressive disorders. We review the various approaches to classifying behavioral and emotional dysregulation in preschoolers and determining the boundaries between normative variation and clinically significant presentations. While highlighting the limitations of the current DSM-IV diagnostic criteria for identifying preschool psychopathology and reviewing alternative diagnostic approaches, we also present evidence supporting the reliability and validity of developmentally appropriate criteria for diagnosing psychiatric disorders in children as young as two years old. Despite the relative lack of research on preschool psychopathology compared with studies of the epidemiology of psychiatric disorders in older children, the current evidence now shows quite convincingly that the rates of the common child psychiatric disorders and the patterns of comorbidity among them in preschoolers are similar to those seen in later childhood. We review the implications of these conclusions for research on the etiology, nosology, and development of early onset of psychiatric disorders, and for targeted treatment, early intervention and prevention with young children.

Childhood temperament and family environment as predictors of internalizing and externalizing trajectories from ages 5 to 17

Childhood temperament and family environment have been shown to predict internalizing and externalizing behavior; however, less is known about how temperament and family environment interact to predict changes in problem behavior. We conducted latent growth curve modeling on a sample assessed at ages 5, 7, 10, 14, and 17 (N = 337). Externalizing behavior decreased over time for both sexes, and internalizing behavior increased over time for girls only. Two childhood variables (fear/shyness and maternal depression) predicted boys' and girls' age-17 internalizing behavior, harsh discipline uniquely predicted boys' age-17 internalizing behavior, and maternal depression and lower family income uniquely predicted increases in girls' internalizing behavior. For externalizing behavior, an array of temperament, family environment, and Temperament x Family Environment variables predicted age-17 behavior for both sexes. Sex differences were present in the prediction of externalizing slopes, with maternal depression predicting increases in boys' externalizing behavior only when impulsivity was low, and harsh discipline predicting increases in girls' externalizing behavior only when impulsivity was high or when fear/shyness was low.

5-HT 1A polymorphism and self-transcendence in mood disorders

Recently, an association between serotonin 1A receptor binding potential and self-transcendence scores at the temperament and character inventory (TCI) has been reported. We tested involvement of 5-HT(1A) gene in this trait, in a sample of 40 remitted mood disorder patients. Subjects with the 5-HT(1A)*C/C genotype showed significantly lower scores at the total self-transcendence and at the sub-scales of transpersonal identification and spiritual acceptance. Our preliminary results further support the involvement of the serotoninergic pattern in the self-transcendence character trait.

XBP1 gene polymorphism (-116C/G) and personality

Recently, a polymorphism of the XBP1 gene (-116 C/G) was observed to play a significant role in the development of bipolar mood disorder from the Japanese population. The present study investigated a role of the polymorphism in the development of personality in healthy Japanese volunteers (n = 195). Personality traits were evaluated using NEO Personality Inventory-Revised (NEO PI-R). As a result, a statistical trend for association between the polymorphism (genotype) and the NEO PI-R scores of agreeableness and neuroticism was observed (ANOVA, P = 0.01 and 0.006, respectively). Subjects with the G allele, especially those with G-G genotype, tended to show lower neuroticism and higher agreeableness in the present study. The result is provisional and should be interpreted with caution, partly because the previous study suggested the allele as a risk allele for bipolar disorder. Further studies are required to confirm the results.

The feasibility of neuropsychological endophenotypes in the search for genes associated with bipolar affective disorder

OBJECTIVE

Efforts to identify genetic loci for bipolar disorder (BPD) have thus far proved elusive. The identification of processes mediating between genotype and phenotype (endophenotypes) may help resolve the carrier status of family members in genetic studies of polygenetic disorders with imperfect penetrance, such as BPD. We reviewed the literature to determine if neuropsychological measures could be used as effective endophenotypes to aid molecular genetic studies searching for genes predisposing to BPD.

METHODS

Four prerequisites for endophenotypic markers are described, and a critical review of relevant literature was undertaken to determine if neurocognitive measures satisfy these four requirements in BPD.

RESULTS

We found evidence that executive functions and declarative memory may be candidate neurocognitive endophenotypes for BPD. However, we cannot exclude other areas of cognition as being affected by BPD susceptibility genes, given the limits of the current knowledge of the neuropsychology of BPD. In particular, the paucity of studies measuring cognition in healthy relatives of BPD patient limits conclusion regarding familial aggregation of particular neurocognitive deficits (i.e. attention). Furthermore, the effects of clinical state and/or medication usage on cognitive functioning in BPD probands should be further explored.

CONCLUSIONS

Molecular genetic studies of BPD may benefit from the application of select neuropsychological measures as endophenotypic markers. The use of these markers, once defined, may improve power for detecting genes predisposing to BPD and may help to better define diagnostic criteria.

Suicide prevention program for the elderly: the experience in Japan

In this article, the author describes a suicide prevention program for the elderly in Japan carried out in a small town, Nagawamachi, Aomori. Because of the recent sharp increase in this town in the rate of suicides, we started to develop a suicide prevention program with the goal of trying to detect depression in its early stages. At first we adopted various questionnaires and used structured interviews, and then developed a screener for depression. Screening is an important part of our suicide prevention program, because elderly who are suicidal often do not recognize their distress is a treatable medical condition, partly due to a negative image of mental illness, and most of them do not seek medical help. The author underscores the importance of educational programs to address how to recognize the symptoms of depression and to develop a community network for the elderly to communicate with locals and support each other. It is also important to focus on a social schema to produce a society that respects "being" and not just "doing".