A genetic analysis of the validity of the Hypomanic Personality Scale

Exploring the effects of family and life events on genetic and environmental architecture of schizotypal and hypomanic dimensions: Insights from a twin study

BACKGROUND

Strategies of prevention for psychiatric disorders need a deep understanding of the aetiological factors involved in the psychopathological processes. Our twin study aims at disentangling the contributions of genes and environment to schizotypal and hypomanic dimensions, considering the role of stressful life events (LEs) and the quality of family relationships.

METHODS

The Magical Ideation Scale (MIS) and Perceptual Aberration Scale (PAS) were used to assess positive schizotypy, while Hypomanic Personality Scale (HPS) and its sub-scales were used to investigate proneness to affective disorders. 268 twins (54.5 % female; aged 18.0 ± 6.68) were included. Participants filled out a questionnaire on LEs and their parents provided an evaluation of intra-family relationship (Relationship Quality Index, RQI). Classic univariate twin models for quantitative traits were fitted for scales, and the effects of covariates (LEs and RQI) were assessed.

RESULTS

For MIS, HPS and its sub-scales, significant common and unique environmental effects were detected, with genetic factors affecting only HPS Social Vitality sub-scale. Unique environment was the only source of variance of PAS score. The number of recent LEs influenced MIS and PAS models, while RQI score affected MIS model.

LIMITATIONS

The main limitation of the study is the small sample size, which reduces statistical power and may potentially lead to an underestimation of heritability. Additionally, the cross-sectional design limits the possibility to draw causal considerations.

CONCLUSIONS

Findings provide preliminary evidence for a significant environmental role in modulating states of vulnerability. Moreover, the expression of positive schizotypy resulted influenced by recent stressors and intra-family relationships.

Impact of hypomanic personality traits on brain functional connectivity during a dynamic theory-of-mind task

Hypomanic personality traits are present in the general population and represent a risk factor for developing bipolar disorder. This personality style, notably its social component, is linked to difficulties in theory of mind (i.e., ability to infer mental states). Exploring the neural correlates of mental states' inference in individuals with these personality traits can provide meaningful insights into the development of bipolar disorder. The aim of the present study was therefore to investigate the potential impact of hypomanic traits on brain activation and task-based connectivity strength during a dynamic theory of mind task in a nonclinical population. A total of 52 nonclinical participants were recruited, and hypomanic traits were assessed with the Hypomanic Personality Scale. The severity of hypomanic traits was positively associated with right middle and inferior frontal gyri activations (in high vs. low inference in nonemotional condition and emotion vs. no emotion in high inference, respectively). It was also associated with stronger connectivity between the salience network (i.e., bilateral putamen and pallidum) and bilateral superior temporal gyri (high inference in nonemotional condition), and between cerebellar and temporal areas (high inference in emotional condition). These changes may either reflect adaptations or differential processing, and further studies are therefore mandatory.

Deficits in explicit emotion regulation in bipolar disorder: a systematic review

Background

This study aimed to compile and synthesize studies investigating explicit emotion regulation in patients with bipolar disorder and individuals at risk of developing bipolar disorder. The importance of explicit emotion regulation arises from its potential role as a marker for bipolar disorders in individuals at risk and its potent role in therapy for bipolar disorder patients.

Methods

To obtain an exhaustive compilation of studies dealing specifically with explicit emotion regulation in bipolar disorder, we conducted a systematic literature search in four databases. In the 15 studies we included in our review, the emotion-regulation strategies maintenance, distraction, and reappraisal (self-focused and situation-focused) were investigated partly on a purely behavioral level and partly in conjunction with neural measures. The samples used in the identified studies included individuals at increased risk of bipolar disorder, patients with current affective episodes, and patients with euthymic mood state.

Results

In summary, the reviewed studies' results indicate impairments in explicit emotion regulation in individuals at risk for bipolar disorder, patients with manic and depressive episodes, and euthymic patients. These deficits manifest in subjective behavioral measures as well as in neural aberrations. Further, our review reveals a discrepancy between behavioral and neural findings regarding explicit emotion regulation in individuals at risk for bipolar disorders and euthymic patients. While these groups often do not differ significantly in behavioral measures from healthy and low-risk individuals, neural differences are mainly found in frontostriatal networks.

Conclusion

We conclude that these neural aberrations are a potentially sensitive measure of the probability of occurrence and recurrence of symptoms of bipolar disorders and that strengthening this frontostriatal route is a potentially protective measure for individuals at risk and patients who have bipolar disorders.

Hypomania and saccadic changes in Parkinson's disease: influence of D2 and D3 dopaminergic signalling

In order to understand the influence of two dopaminergic signalling pathways, TaqIA rs1800497 (influencing striatal D2 receptor density) and Ser9Gly rs6280 (influencing the striatal D3 dopamine-binding affinity), on saccade generation and psychiatric comorbidities in Parkinson’s disease, this study aimed to investigate the association of saccadic performance in hypomanic or impulsive behaviour in parkinsonian patients; besides we questioned whether variants of D2 (A1+/A1−) and D3 (B1+/B1−) receptor polymorphism influence saccadic parameters differently, and if clinical parameters or brain connectivity changes modulate this association in the nigro-caudatal and nigro-collicular tract. Initially, patients and controls were compared regarding saccadic performance and differed in the parameter duration in memory-guided saccades (MGS) and visually guided saccades (VGS) trials (p < 0.0001) and in the MGS trial (p < 0.03). We were able to find associations between hypomanic behaviour (HPS) and saccade parameters (duration, latency, gain and amplitude) for both conditions [MGS (p = 0.036); VGS (p = 0.033)], but not for impulsive behaviour. For the A1 variant duration was significantly associated with HPS [VGS (p = 0.024); MGS (p = 0.033)]. In patients with the B1 variant, HPS scores were more consistently associated with duration [VGS (p = 0.005); MGS (p = 0.015), latency [VGS (p = 0.022)]] and amplitude [MGS (p = 0.006); VGS (p = 0.005)]. The mediation analysis only revealed a significant indirect effect for amplitude in the MGS modality for the variable UPDRS-ON (p < 0.05). All other clinical scales and brain connectivity parameters were not associated with behavioural traits. Collectively, our findings stress the role of striatal D2 and D3 signalling mechanisms in saccade generation and suggest that saccadic performance is associated with the clinical psychiatric state in Parkinson’s disease.

Vulnerability to bipolar disorder is linked to sleep and sleepiness

Sleep impairments are a hallmark of acute bipolar disorder (BD) episodes and are present even in the euthymic state. Studying healthy subjects who are vulnerable to BD can improve our understanding of whether sleep impairment is a predisposing factor. Therefore, we investigated whether vulnerability to BD, dimensionally assessed by the hypomanic personality scale (HPS), is associated with sleep disturbances in healthy subjects. We analyzed participants from a population-based cohort who had completed the HPS and had either a 7-day actigraphy recording or a Pittsburgh sleep quality index (PSQI) assessment. In addition, subjects had to be free of confounding diseases or medications. This resulted in 771 subjects for actigraphy and 1766 for PSQI analyses. We found strong evidence that higher HPS scores are associated with greater intraindividual sleep variability, more disturbed sleep and more daytime sleepiness. In addition, factor analyses revealed that core hypomanic features were especially associated with self-reported sleep impairments. Results support the assumption of disturbed sleep as a possibly predisposing factor for BD and suggest sleep improvement as a potential early prevention target.

Looking on the bright side and seeing it vividly: interpretation bias and involuntary mental imagery are related to risk for bipolar disorder

BACKGROUND

Involuntary mental imagery is elevated among people with bipolar disorder, and has been shown to shape biases in interpretation of ambiguous information. However, it is not clear whether biases in interpretation of ambiguous scenarios can be observed in those at risk for bipolar disorder, or whether involuntary imagery is related to such a bias.

AIMS

In the present study, we extended a prominent model of bipolar cognition to an at-risk sample. We specifically tested whether positive interpretation bias and involuntary mental imagery are linked to a greater risk of bipolar disorder.

METHOD

Young adults (N = 169) completed measures of risk for bipolar disorder (the Hypomanic Personality Scale [HPS]), interpretation bias, and involuntary mental imagery.

RESULTS

Higher scores on the HPS were significantly correlated with more positive interpretations of ambiguous scenarios (β = 0.29, p <. 01) and more frequent involuntary mental imagery (β = 0.22, p < .01). There was no evidence of an interaction between interpretation bias and mental imagery in predicting HPS score, β = .04, p = .62.

CONCLUSIONS

Further research is warranted to determine if intrusive imagery or interpretation bias influence the development of bipolar disorder over time in those at risk.

Modulation of the N400 component in relation to hypomanic personality traits in a word meaning ambiguity resolution task

AIM

High levels of hypomanic personality traits have been associated with an increased risk of developing bipolar disorder (BD). Changes in semantic content, impaired verbal associations, abnormal prosody, and abnormal speed of language are core features of BD, and are thought to be related to semantic processing abnormalities. In the present study, we used event-related potentials to investigate the relation between semantic processing (N400 component) and hypomanic personality traits.

METHODS

We assessed 65 healthy young adults on the Hypomanic Personality Scale (HPS). Event-related potentials were recorded during a semantic ambiguity resolution task exploring semantic ambiguity (polysemous word ending a sentence) and congruency (target word semantically related to the sentence).

RESULTS

As expected, semantic ambiguity and congruency both elicited an N400 effect across our sample. Correlation analyses showed a significant positive relationship between the Social Vitality subscore of the HPS and N400 modulation in the frontal region of interest in the incongruent unambiguous condition, and in the frontocentral region of interest in the incongruent ambiguous condition.

CONCLUSION

We found differences in semantic processing (i.e., detection of incongruence and semantic inhibition) in individuals with higher Social Vitality subscores. In the light of the literature, we discuss the notion that a semantic processing impairment could be a potential marker of vulnerability to BD, and one that needs to be explored further in this clinical population.

The link between hypomania risk and creativity: The role of heightened behavioral activation system (BAS) sensitivity

BACKGROUND

The relationship between bipolar disorder (BD) and creativity is well-known; however, relatively little is known about its potential mechanism. We investigated whether heightened behavioral activation system (BAS) sensitivity may mediate such relationship.

METHODS

Korean young adults (N=543) completed self-report questionnaires that included the Hypomanic Personality Scale (HPS), the Behavioral Activation System(BAS) Scale, the Everyday Creativity Scale (ECS), the Positive Affect and Negative Affect Schedule (PANAS), and the Altman Self-Rating Mania Scale (ASRM). Correlational, hierarchical regression and mediation analyses using bootstrap confidence intervals were conducted.

RESULTS

As predicted, BAS sensitivity was associated with self-reported creativity as well as hypomania risk and symptoms. Even when positive affect was controlled, BAS sensitivity predicted incrementally significant variance in explaining creativity. In mediation analysis, BAS sensitivity partially mediated the relation between hypomania risk and creativity.

LIMITATIONS

Reliance on self-report measures in assessing creativity and usage of non-clinical sample.

CONCLUSIONS

BAS sensitivity was related not only to mood pathology but also to creativity. As a basic affective temperament, BAS sensitivity may help explain incompatible sides of adaptation associated with BD.

Research Domain Criteria versus DSM V: How does this debate affect attempts to model corticostriatal dysfunction in animals?

For decades, the nosology of mental illness has been based largely upon the descriptions in the Diagnostic and Statistical Manual of the American Psychiatric Association (DSM). A recent challenge to the DSM approach to psychiatric nosology from the National Institute on Mental Health (USA) defines Research Domain Criteria (RDoC) as an alternative. For RDoC, psychiatric illnesses are not defined as discrete categories, but instead as specific behavioral dysfunctions irrespective of DSM diagnostic categories. This approach was driven by two primary weaknesses noted in the DSM: (1) the same symptoms occur in very different disease states; and (2) DSM criteria lack grounding in the underlying biological causes of mental illness. RDoC intends to ground psychiatric nosology in those underlying mechanisms. This review addresses the suitability of RDoC vs. DSM from the view of modeling mental illness in animals. A consideration of all types of psychiatric dysfunction is beyond the scope of this review, which will focus on models of conditions associated with frontostriatal dysfunction.

Emotion regulation and mania risk: Differential responses to implicit and explicit cues to regulate

BACKGROUND AND OBJECTIVES

People prone to mania use emotion regulation (ER) strategies well when explicitly coached to do so in laboratory settings, but they find these strategies ineffective in daily life. We hypothesized that, compared with control participants, mania-prone people would show ER deficits when they received implicit, but not explicit, cues to use ER.

METHODS

Undergraduates (N = 66) completed the Hypomanic Personality Scale (HPS) and were randomly assigned to one of three experimental conditions: automatic ER (scrambled sentence primes), deliberate ER (verbal instructions), or control (no priming or instructions to use ER). Then, participants played a videogame designed to evoke anger. Emotion responses were measured with a multi-modal assessment of self-reported affect, psychophysiology, and facial expressions. Respiratory sinus arrhythmia (RSA) was used to index ER.

RESULTS

The videogame effectively elicited subjective anger, angry facial expressions, and heart rate increases when keys malfunctioned. As hypothesized, persons who were more mania prone showed greater RSA increases in the deliberate ER condition than in the automatic or control conditions.

LIMITATIONS

One potential limitation is the use of an analog sample.

CONCLUSIONS

Findings suggest that those at risk for mania require more explicit instruction to engage ER effectively.

Differentiating risk for mania and borderline personality disorder: The nature of goal regulation and impulsivity

Researchers and clinicians have long noted the overlap among features and high comorbidity of bipolar disorder and borderline personality disorder. The shared features of impulsivity and labile mood in both disorders make them challenging to distinguish. We tested the hypothesis that variables related to goal dysregulation would be uniquely related to risk for mania, while emotion-relevant impulsivity would be related to risk for both disorders. We administered a broad range of measures related to goal regulation traits and impulsivity to 214 undergraduates. Findings confirmed that risk for mania, but not for borderline personality disorder, was related to higher sensitivity to reward and intense pursuit of goals. In contrast, borderline personality disorder symptoms related more strongly than did mania risk with threat sensitivity and with impulsivity in the context of negative affect. Results highlight potential differences and commonalities in mania risk versus borderline personality disorder risk.

Creativity is linked to ambition across the bipolar spectrum

OBJECTIVE

Beyond evidence for an association, little is known about the mechanism linking creativity bipolar spectrum conditions. Theory suggests that ambition, which is heightened in bipolar disorder (BD) and associated with creativity in the general population, might be an important variable. The overarching aim of this project was to evaluate whether ambition is related to creativity among those with bipolar spectrum conditions.

METHOD

Across two studies, we examined correlations between a validated self-report measure of ambition, the WASSUP, and creativity. In Study One, 22 individuals diagnosed with BD who self-identified as highly creative completed the WASSUP and a measure of lifetime creative accomplishment. In Study Two, 221 undergraduates completed the WASSUP, a measure of mania risk (the Hypomanic Personality Scale, HPS) and a measure designed to assess creativity in business projects and tasks.

RESULTS

In Study One, WASSUP scores were significantly elevated compared to normative levels in BD, and WASSUP scores were correlated with lifetime creative accomplishment within the artistic sample. In Study Two, mania risk was related to greater ambition and creativity, and ambition was also directly related to greater creativity.

LIMITATIONS

Both studies were limited by the reliance on self-reported ambition.

CONCLUSION

Ambition could be one important component of creative success across the bipolar spectrum.

Manic tendencies are not related to being an entrepreneur, intending to become an entrepreneur, or succeeding as an entrepreneur

BACKGROUND

Popular literature suggests a relationship between entrepreneurship and manic tendencies, yet little scientific research has evaluated whether manic tendencies foster entrance into entrepreneurial roles, intent to become an entrepreneur, or success as an entrepreneur.

METHODS

In study 1, 225 undergraduates and business school students/affiliates took an online survey to assess engagement and intent as entrepreneurs, as well as manic tendencies, including family diagnoses as reported on the Family Index of Risk for Mania, subsyndromal manic tendencies as assessed with the Hypomanic Personality Scale, and self-reported diagnoses. In study 2, the sample of entrepreneurs identified in study 1 was enriched by recruiting a larger group of established entrepreneurs from the community. Entrepreneurs (n=210) completed items concerning their success in entrepreneurship, and we examined whether the three measures of manic tendencies were related to success.

RESULTS

There was no evidence that those vulnerable to mania, regardless of definition, were more likely to be entrepreneurs, to intend to become entrepreneurs, or to succeed as entrepreneurs.

LIMITATIONS

The studies were limited by self-report measures and relatively small samples.

CONCLUSIONS

More nuanced models may explain the frequent clinical observations of manic traits among entrepreneurs.