Emotional and physiological responses to normative and idiographic positive stimuli in bipolar disorder

BACKGROUND

Few studies have examined differences in emotional responding among distinct types of positive stimuli. This is important to understand both for individuals characterized by extreme positive mood (i.e., bipolar disorder) and healthy adults.

METHODS

Using a multi-method within-subjects design, the current study examined physiological, behavioral, and self-reported responses to normative (film) and idiographic (memory) happy stimuli in bipolar (BD; n=25) and healthy control groups (CTL; n=23).

RESULTS

For both groups, the happy films were associated with greater self-reported and behavioral displays of positive emotion compared to the happy memory. Furthermore, the BD group displayed greater cardiac vagal tone - a putative marker of positive emotion - across both the film and memory.

CONCLUSION

Normative stimuli were more potent elicitors of positive emotion compared to idiographic stimuli. The study provided further evidence for cardiac vagal tone as a potential biomarker of extreme positive emotion in BD.

Feeling stuck in the present? Mania proneness and history associated with present-oriented time perspective

Humans have the ability to mentally time travel through past, present, and future. But can a disruption in emotion characteristic of emotional disorders cause this ability to unwind, leaving people "stuck" in the present emotional moment? Two studies are presented that examine emotional time-perspective in a disorder (mania) characterized by present-oriented tendencies, including impulsivity and emotion dysregulation. In Study 1, associations were reported between mania proneness and emotion time-perspective (n = 509), and Study 2 compared emotion time-perspective between individuals with a clinical history of mania (n = 32), and controls (n = 30). We show that mania is associated with increased present and decreased future focus. These findings suggest that emotional disorders can be understood, at least in part, by examining how people understand and use time to guide their behavior and feelings.

Can Feeling Too Good Be Bad?

Positive emotions are vital to attaining important goals, nurturing social bonds, and promoting cognitive flexibility. However, one question remains relatively unaddressed: Can positive emotions also be a source of dysfunction and negative outcomes? An ideal point of entry to understand how positive emotion can go awry is bipolar disorder, a psychiatric disorder marked by abnormally elevated positive emotion. In this review I provide an overview of recent experimental evidence from individuals at risk for, and diagnosed with, bipolar disorder. I present a novel account of positive-emotion disturbance, referred to as positive emotion persistence (PEP), and consider potential mechanisms. The central thesis guiding PEP is that persistent activation of positive emotion across contexts and not solely in response to positive or rewarding stimuli is a marker of emotion dysfunction in bipolar disorder. I discuss implications for the study of bipolar disorder and positive emotion generally.

Hypersomnia in inter-episode bipolar disorder: does it have prognostic significance?

BACKGROUND

Hypersomnia in inter-episode bipolar disorder has been minimally researched. The current study sought to document the prevalence of hypersomnia in a sample of inter-episode patients with bipolar disorder and to examine the relationship between hypersomnia and future bipolar depressive symptoms.

METHODS

A total of 56 individuals with bipolar disorder (51 type I+5 type II) who were currently inter-episode, along with 55 non-psychiatric controls, completed a baseline assessment, including semi-structured interviews for psychiatric diagnoses, sleep disorders, and a battery of indices that included assessment of hypersomnia. Approximately 6 months later, participants were recontacted by telephone and mood was re-evaluated.

RESULTS

Three of six indices suggested that approximately 25% of participants with bipolar disorder endorsed symptoms of hypersomnia in the inter-episode period. Within the bipolar group, hypersomnia in the inter-episode period was associated with future depressive symptoms. This finding was independent of baseline depressive symptoms and medication use.

LIMITATIONS

Small sample size and concurrent psychopharmacology in the bipolar sample.

DISCUSSION

Though no gold standard measure for hypersomnia currently exists, this research takes a step towards identifying a clinically and empirically useful hypersomnia assessment. This study demonstrates that hypersomnia in the inter-episode period of bipolar disorder relates to future depressive symptoms, and adds to the growing body of evidence on the importance of inter-episode symptoms predicting bipolar relapse.

A discrete emotions approach to positive emotion disturbance in depression

Converging findings suggest that depressed individuals exhibit disturbances in positive emotion. No study, however, has ascertained which specific positive emotions are implicated in depression. We report two studies that compare how depressive symptoms relate to distinct positive emotions at both trait and state levels of assessment. In Study 1 (N=185), we examined associations between depressive symptoms and three trait positive emotions (pride, happy, amusement). Study 2 compared experiential and autonomic reactivity to pride, happy, and amusement film stimuli between depressive (n=24; DS) and non-depressive (n=31; NDS) symptom groups. Results indicate that symptoms of depression were most strongly associated with decreased trait pride and decreased positive emotion experience to pride-eliciting films. Discussion focuses on the implications these findings have for understanding emotion deficits in depression as well as for the general study of positive emotion.

A Dark Side of Happiness? How, When, and Why Happiness Is Not Always Good

Happiness is generally considered a source of good outcomes. Research has highlighted the ways in which happiness facilitates the pursuit of important goals, contributes to vital social bonds, broadens people’s scope of attention, and increases well-being and psychological health. However, is happiness always a good thing? This review suggests that the pursuit and experience of happiness might sometimes lead to negative outcomes. We focus on four questions regarding this purported “dark side” of happiness. First, is there a wrong degree of happiness? Second, is there a wrong time for happiness? Third, are there wrong ways to pursue happiness? Fourth, are there wrong types of happiness? Cumulatively, these lines of research suggest that although happiness is often highly beneficial, it may not be beneficial at every level, in every context, for every reason, and in every variety.

Hooked on a feeling: rumination about positive and negative emotion in inter-episode bipolar disorder

Rumination has been consistently implicated in the onset and maintenance of depression. Less work has examined rumination in the context of bipolar disorder, especially rumination about positive emotion. The present study examined rumination about negative and positive emotion in interepisode bipolar disorder (BD; n = 39) and healthy controls (CTL; n = 34). Trait rumination about positive and negative emotion, as well as experiential and physiological responses to a rumination induction, was measured. Illness course was also assessed for the BD group. Results indicated that the BD group reported greater trait rumination about positive and negative emotion compared with the CTL group, though no group differences emerged during the rumination induction. For the BD group, trait rumination about positive and negative emotion, as well as increased cardiovascular arousal (i.e., heart rate), was associated with greater lifetime depression frequency; trait rumination about positive emotion was associated with greater lifetime mania frequency. These findings suggest that interepisode BD is associated with greater rumination about positive and negative emotion, which in turn is associated with illness course.

The effect of dichloroacetate on health- and lifespan in C. elegans

Aging is associated with increased vulnerability to chronic, degenerative diseases and death. Strategies for promoting healthspan without necessarily affecting lifespan or aging rate have gained much interest. The mitochondrial free radical theory of aging suggests that mitochondria and, in particular, age-dependent mitochondrial decline play a central role in aging, making compounds that affect mitochondrial function a possible strategy for the modulation of healthspan and possibly the aging rate. Here we tested such a "metabolic tuning" approach in nematodes using the mitochondrial modulator dichloroacetate (DCA). We explored DCA as a proof-of-principle compound to alter mitochondrial parameters in wild-type animals and tested whether this approach is suitable for reducing reactive oxygen species (ROS) production and for improving organismal health- and lifespan. In parallel, we addressed the potential problem of operator bias by running both unblinded and blinded lifespan studies. We found that DCA treatment (1) increased ATP levels without elevating oxidative protein damage and (2) reduced ROS production in adult C. elegans. DCA treatment also significantly prolonged nematode health- and lifespan, but did not strongly impact mortality doubling time. Operator blinding resulted in considerably smaller lifespan-extending effects of DCA. Our data illustrate the promise of a "metabolic tuning" intervention strategy, emphasize the importance of mitochondria in nematode aging and highlight operator bias as a potential confounder in lifespan studies.

Sleep architecture as correlate and predictor of symptoms and impairment in inter-episode bipolar disorder: taking on the challenge of medication effects

This study was designed to clarify the association between inter-episode bipolar disorder (BD) and sleep architecture. Participants completed a baseline symptom and sleep assessment and, 3 months later, an assessment of symptoms and impairment. The effects of psychiatric medications on sleep architecture were also considered. Participants included 22 adults with BD I or II (inter-episode) and 22 non-psychiatric controls. The sleep assessment was conducted at the Sleep and Psychological Disorders Laboratory at the University of California, Berkeley. Follow-up assessments 3 months later were conducted over the phone. Results indicate that, at the sleep assessment, BD participants exhibited greater rapid eye movement sleep (REM) density than control participants with no other group differences in sleep architecture. Sleep architecture was not correlated with concurrent mood symptoms in either group. In the BD group, duration of the first REM period and slow-wave sleep (SWS) amount were positively correlated with manic symptoms and impairment at 3 months, while REM density was positively correlated with depressive symptoms and impairment at 3 months. The amount of Stage 2 sleep was negatively correlated with manic symptoms and impairment at 3 months. In contrast, for the control group, REM density was negatively correlated with impairment at 3 months. SWS and Stage 2 sleep were not correlated with symptoms or impairment. Study findings suggest that inter-episode REM sleep, SWS and Stage 2 sleep are correlated with future manic and depressive symptoms and impairment in BD. This is consistent with the proposition that sleep architecture may be a mechanism of illness maintenance in BD.

Immunogenicity of purified venezuelan equine encephalitis virus inactivated by ionizing radiation

Purified and concentrated Venezuelan equine encephalitis (VEE) virus derived from tissue cultures, rendered noninfectious by ionizing radiation with retention of in vitro serological activity, also retained a high level of immunogenicity. In mice, fluid vaccines afforded excellent protection against lethal challenge with homologous Trinidad strain VEE virus. A direct relationship was observed between concentration of vaccine or number of injections and survival. One intraperitoneal inoculation of undiluted vaccine protected essentially all mice challenged 21 days later with 100,000 mouse intraperitoneal LD(50) of virus. Similarly, mice receiving three injections of vaccines diluted 1:100 were completely protected. Noninfectious VEE virus preparations combined with adjuvant 65, a nontoxic metabolizable vehicle, were likewise very effective in protecting mice immunized intraperitoneally or subcutaneously against lethal challenge. Guinea pigs immunized subcutaneously with adjuvant-combined vaccine survived lethal challenge of 1,000,000 guinea pig intraperitoneal LD(50).

Sleep, illness course, and concurrent symptoms in inter-episode bipolar disorder

We investigated associations between sleep, illness course, and concurrent symptoms in 21 participants with bipolar disorder who were inter-episode. Sleep was assessed using a week-long diary. Illness course and symptoms were assessed via validated semi-structured interviews. Lower and more variable sleep efficiency and more variable total wake time were associated with more lifetime depressive episodes. Variability in falling asleep time was positively correlated with concurrent depressive symptoms. Sleep efficiency was positively correlated with concurrent manic symptoms. These findings suggest that inter-episode sleep disturbance is associated with illness course and that sleep may be an important intervention target in bipolar disorder.

The effect of mood on sleep onset latency and REM sleep in interepisode bipolar disorder

The present study investigates whether interepisode mood regulation impairment contributes to disturbances in sleep onset latency (SOL) and rapid eye movement (REM) sleep. Individuals with interepisode bipolar disorder (n = 28) and healthy controls (n = 28) slept in the laboratory for 2 baseline nights, a happy mood induction night, and a sad mood induction night. There was a significant interaction whereby on the happy mood induction night the bipolar group exhibited significantly longer SOL than did the control group, while there was no difference on the baseline nights. In addition, control participants exhibited shorter SOL on the happy mood induction night compared to the baseline nights, a finding that was not observed in the bipolar group. On the sad mood induction night, participants in both groups had shorter SOL and increased REM density when compared to the baseline nights. Bipolar participants exhibited heightened REM density compared to control participants on both nights. These results raise the possibility that regulation of positive stimuli may be a contributor to difficulties with SOL, while hyperactivity may be characteristic of REM sleep.

Smile intensity and warm touch as thin slices of child and family affective style

The authors investigate the claim that thin slices of expressive behavior serve as reliable indicators of affective style in children and their families. Using photographs, the authors assessed smile intensity and tactile contact in kindergartners and their families. Consistent with claims that smiling and touch communicate positive emotion, measures of children's smile intensity and warm family touch were correlated across classroom and family contexts. Consistent with studies of parent-child personality associations, parents' warm smiles and negative facial displays resembled those of their children. Finally, consistent with observed relations between adult personality and positive display, children's smiling behavior in the classroom correlated with parent ratings of children's Extraversion/Surgency. These results highlight the utility of thin slices of smiling and touch as indicators of child and family affective style.

Reflective and ruminative processing of positive emotional memories in bipolar disorder and healthy controls

Recent evidence suggests that reflective (i.e., distanced-why), as compared to ruminative (i.e., immersed-why), processing of negative memories is associated with reductions in negative affect. The present study extended this line of work by examining the effect of these two processing conditions on positive memories among persons with bipolar disorder (BD; n = 27) and a healthy control group (CT; n = 27). After a resting baseline period, participants were instructed to recall a happy autobiographical memory. Using a within-subjects design, participants were asked to process the happy memory in two different experimental conditions (reflective, ruminative) while their experiential, behavioral, and autonomic responses were measured. Consistent with hypotheses, reflective processing was associated with lower self-reported positive affect, positive thoughts, and heart rate compared to ruminative processing for all participants. When current symptoms were controlled for, BD participants reported greater positive affect across both conditions relative to CT participants. Prospective studies are needed to test the extent to which processing of positive emotion contributes to the course of symptoms in bipolar disorder.

Resting respiratory sinus arrhythmia is associated with tonic positive emotionality

Resting respiratory sinus arrhythmia (RSAREST) indexes important aspects of individual differences in emotionality. In the present investigation, the authors address whether RSAREST is associated with tonic positive or negative emotionality, and whether RSAREST relates to phasic emotional responding to discrete positive emotion-eliciting stimuli. Across an 8-month, multiassessment study of first-year university students (n = 80), individual differences in RSAREST were associated with positive but not negative tonic emotionality, assessed at the level of personality traits, long-term moods, the disposition toward optimism, and baseline reports of current emotional states. RSAREST was not related to increased positive emotion, or stimulus-specific emotion, in response to compassion-, awe-, or pride-inducing stimuli. These findings suggest that resting RSA indexes aspects of a person's tonic positive emotionality.

Positive Emotional Traits and Ambitious Goals among People at Risk for Mania: The Need for Specificity

Recent psychosocial theories implicate disturbances in reward pursuit among individuals putatively at risk for mania. The present study examined associations of a measure of risk for mania (the Hypomanic Personality Scale; HPS) with both four trait positive emotions (joy, pride, compassion, and love) and ambitious life goals in five domains (fame, wealth, political influence, family, and friends) among 302 participants from two university settings. Findings indicated that higher HPS scores were related to reward (joy) and achievement-focused (pride) positive emotions, with weaker relations to prosocial (compassion, love) positive emotions. HPS scores were more robustly related to extrinsic (fame, politics) as compared to other-oriented (friends, family) ambitious life goals, with the exception of wealth. These effects were independent of current symptoms of mania and depression. Discussion focuses on the implications of elevated reward and achievement-related positive emotions and goals in understanding risk factors for mania.

Do positive emotions predict symptomatic change in bipolar disorder?

OBJECTIVES

Bipolar disorder is associated with positive emotion disturbance, though it is less clear which specific positive emotions are affected.

METHODS

The present study examined differences among distinct positive emotions in recovered bipolar disorder (BD) patients (n = 55) and nonclinical controls (NC) (n = 32) and whether they prospectively predicted symptom severity in patients with BD. At baseline, participants completed self-report measures of several distinct trait positive emotions. Structured assessments of diagnosis and current mood symptoms were obtained for BD participants. At a six-month follow-up, a subset of BD participants' (n = 39) symptoms were reassessed.

RESULTS

BD participants reported lower joy, compassion, love, awe, and contentment compared to NC participants. BD and NC participants did not differ in pride or amusement. For BD participants, after controlling for baseline symptom severity, joy and amusement predicted increased mania severity, and compassion predicted decreased mania severity at the six-month follow-up. Furthermore, amusement predicted increased depression severity and pride predicted decreased severity of depression. Awe, love, and contentment did not predict symptom severity.

CONCLUSIONS

These results are consistent with a growing literature highlighting the importance of positive emotion in the course of bipolar disorder.

Sleep functioning in relation to mood, function, and quality of life at entry to the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD)

BACKGROUND

Sleep disturbance in bipolar disorder can be both a risk factor and symptom of mood episodes. However, the associations among sleep and clinical characteristics, function, and quality of life in bipolar disorder have not been fully investigated.

METHODS

The prevalence of sleep disturbance, duration, and variability, as well as their associations with mood, function, and quality of life, was determined from 2024 bipolar patients enrolled in the National Institute of Mental Health Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD).

RESULTS

Analyses indicated that 32% of patients were classified as short sleepers, 38% normal sleepers, and 23% long sleepers. Overall, short sleepers demonstrated greater mood elevation, earlier age at onset, and longer illness duration compared to both normal and long sleepers. Both short and long sleepers had greater depressive symptoms, poorer life functioning, and quality of life compared to normal sleepers.

DISCUSSION

Short sleep duration in bipolar disorder was associated with a more severe symptom presentation, whereas both short and long sleep duration are associated with poorer function and quality of life compared to normal sleep duration. Sleep disturbance could be a trait marker of bipolar disorder, though longitudinal assessments are warranted to assess potential causal relations and the longer-term implications of sleep disturbance in bipolar disorder.

Narrating emotional events in schizophrenia

Research has indicated that schizophrenia patients report similar amounts of experienced emotion in response to emotional material compared with nonpatients. However, less is known about how schizophrenia patients describe and make sense of their emotional life events. We adopted a narrative approach to investigate schizophrenia patients' renderings of their emotional life experiences. In Study 1, patients' (n=42) positive and negative narratives were similarly personal, tellable, engaged, and appropriate. However, negative narratives were less grammatically clear than positive narratives, and positive narratives were more likely to involve other people than negative narratives. In Study 2, emotional (positive and negative) narratives were less tellable and detached, yet more linear and social compared with neutral narratives for both schizophrenia patients (n=24) and healthy controls (n=19). However, patients' narratives about emotional life events were less appropriate to context and less linear, and patients' narratives, whether emotional or not, were less tellable and more detached compared with controls' narratives. Although schizophrenia patients are capable of recounting life events that trigger different emotions, the telling of these life events is fraught with difficulty.