On the meaning and measurement of affective instability: clues from chaos theory

Analyzing and identifying predictable time range for stress prediction based on chaos theory and deep learning

Propose

Stress is a common problem globally. Prediction of stress in advance could help people take effective measures to manage stress before bad consequences occur. Considering the chaotic features of human psychological states, in this study, we integrate deep learning and chaos theory to address the stress prediction problem.

Methods

Based on chaos theory, we embed one's seemingly disordered stress sequence into a high dimensional phase space so as to reveal the underlying dynamics and patterns of the stress system, and meanwhile are able to identify the stress predictable time range. We then conduct deep learning with a two-layer (dimension and temporal) attention mechanism to simulate the nonlinear state of the embedded stress sequence for stress prediction.

Results

We validate the effectiveness of the proposed method on the public available Tesserae dataset. The experimental results show that the proposed method outperforms the pure deep learning method and Chaos method in both 2-label and 3-label stress prediction.

Conclusion

Integrating deep learning and chaos theory for stress prediction is effective, and can improve the prediction accuracy over 2% and 8% more than those of the deep learning and the Chaos method respectively. Implications and further possible improvements are also discussed at the end of the paper.

Children's emotional reactivity and negative affect predict future ADHD symptom severity beyond initial ADHD symptom severity

Children with Attention-Deficit/Hyperactivity Disorder (ADHD) often experience significant emotion dysregulation. However, there is limited longitudinal data on associations between multiple aspects of emotion dysregulation and ADHD symptoms. Additionally, given substantial evidence that increased levels and variability of negative affect (NA) are identified in children with ADHD, it is important to examine the role of NA in this relationship. The present study used momentary and longitudinal data to examine the relation between two aspects of emotion dysregulation (emotional lability and emotional reactivity), the two ADHD symptom clusters separately (inattentive and hyperactive/impulsive), total ADHD symptom severity, and NA variability over a period of six months. Participants (N = 68) were parents of children aged 7-12 years old (M = 9.80, SD = 1.34) who completed baseline and 6-month follow-up reports of children's ADHD symptoms and emotion dysregulation as well as ecological momentary assessments (EMA) of their children's NA for one week. Results were threefold: (1) children's emotional reactivity predicted inattentive, hyperactive/impulsive, and total ADHD symptom severity above and beyond initial ADHD symptom severity, but emotional lability did not significantly predict severity of any ADHD symptom cluster; (2) NA variability predicted hyperactive/impulsive and total ADHD symptom severity, but not inattentive severity; and (3) initial ADHD symptom severity did not predict emotion dysregulation at follow-up. The current study provides novel insight regarding the longitudinal influence of specific aspects of emotion dysregulation and NA on ADHD symptom severity in children and suggests that targeting emotional reactivity could minimize ADHD symptom severity.

Advances in Understanding Fractals in Affective and Anxiety Disorders

In this chapter, we review the research that has applied fractal measures to the study of the most common psychological disorders, that is, affective and anxiety disorders. Early studies focused on heart rate, but diverse measures have also been examined, from variations in subjective mood, or hand movements, to electroencephalogram or magnetoencephalogram data. In general, abnormal fractal dynamics in different physiological and behavioural outcomes have been observed in mental disorders. Despite the disparity of variables measured, fractal analysis has shown high sensitivity in discriminating patients from healthy controls. However, and because of this heterogeneity in measures, the results are not straightforward, and more studies are needed in this promising line.

Ecological Momentary Assessment of Youth Anxiety: Evaluation of Psychometrics for Use in Clinical Trials

Background: Ecological momentary assessment (EMA) captures naturalistic experience in real time and holds promise to improve our understanding and treatment of youth psychopathology. While psychometric evaluation of EMA methods is crucial, particularly for use as a tool in clinical trials, research examining the reliability and validity of EMA items in youth is lacking. Method: This study evaluates EMA responses from 204 child and adolescent participants (M age = 12.54, 60.8% female), including 131 participants with an anxiety disorder and 73 participants with no psychiatric diagnosis. We assessed the within- and between-person variability, internal consistency, test-retest reliability, and convergent and discriminant validity of two EMA items probing anxiety symptoms; one positive affect item served as a comparison. Results: All psychometric properties of the anxiety items were at least satisfactory in youth with anxiety disorders. However, there was restricted variability and poor test-retest reliability in youth with no diagnosis. Discussion: These results might facilitate future clinical trials using EMA to investigate pediatric anxiety. Results also suggest that unique EMA items might be needed to reliably track anxiety in healthy youth. Future work should continue to examine the psychometric properties of EMA protocols before implementation in clinical trials. ClinicalTrials.gov identifier: NCT00018057.

Psychometric properties of an innovative smartphone application to investigate the daily impact of hypoglycemia in people with type 1 or type 2 diabetes: The Hypo-METRICS app

INTRODUCTION

The aim of this study was to determine the acceptability and psychometric properties of the Hypo-METRICS (Hypoglycemia MEasurement, ThResholds and ImpaCtS) application (app): a novel tool designed to assess the direct impact of symptomatic and asymptomatic hypoglycemia on daily functioning in people with insulin-treated diabetes.

MATERIALS AND METHODS

100 adults with type 1 diabetes mellitus (T1DM, n = 64) or insulin-treated type 2 diabetes mellitus (T2DM, n = 36) completed three daily 'check-ins' (morning, afternoon and evening) via the Hypo-METRICs app across 10 weeks, to respond to 29 unique questions about their subjective daily functioning. Questions addressed sleep quality, energy level, mood, affect, cognitive functioning, fear of hypoglycemia and hyperglycemia, social functioning, and work/productivity. Completion rates, structural validity, internal consistency, and test-retest reliability were explored. App responses were correlated with validated person-reported outcome measures to investigate convergent (rs>±0.3) and divergent (rs<±0.3) validity.

RESULTS

Participants' mean±SD age was 54±16 years, diabetes duration was 23±13 years, and most recent HbA1c was 56.6±9.8 mmol/mol. Participants submitted mean±SD 191±16 out of 210 possible 'check-ins' (91%). Structural validity was confirmed with multi-level confirmatory factor analysis showing good model fit on the adjusted model (Comparative Fit Index >0.95, Root-Mean-Square Error of Approximation <0.06, Standardized Root-Mean-square Residual<0.08). Scales had satisfactory internal consistency (all ω≥0.5), and high test-retest reliability (rs≥0.7). Convergent and divergent validity were demonstrated for most scales.

CONCLUSION

High completion rates and satisfactory psychometric properties demonstrated that the Hypo-METRICS app is acceptable to adults with T1DM and T2DM, and a reliable and valid tool to explore the daily impact of hypoglycemia.

Grouping of mood symptoms by time series dynamics

BACKGROUND

Understanding how symptoms of mood disorders vary over time in relation to each other is potentially valuable for diagnosis and predicting episodes of illness. In this paper, we characterize the degree of similarity of time series of different mood disorder symptoms.

METHODS

We collected 32,215 mood disorder symptom questionnaires, administered twice-daily over 18 months to (n = 19) subjects with rapidly cycling bipolar disorder and (n = 20) healthy control subjects, using visual analog scales to rate 11 sets of symptom severity ratings plus a control item. We used Dynamic Time Warping to calculate similarity ratings between all within-subject pairs of severity ratings followed by Exploratory Factor Analysis (EFA) to identify latent factors of symptom time series across all subjects.

RESULTS

Two latent factors were identified: one with depression and anxiety; and a second, with concentration, energy, irritability, fatigue, appetite, euphoria/elation and overall mood. Restlessness, racing thoughts, and the control item (daily hours of daylight) did not cluster with any of the others.

LIMITATIONS

Limited sample size dictated that we pool bipolar and healthy patients and use an iterative EFA procedure.

CONCLUSION

This analysis suggests that, in a pooled sample of individuals with bipolar disorder and in healthy controls, severity ratings of overall depression and overall anxiety vary jointly as one dynamic factor, while some but not all other DSM mood symptoms vary jointly along with overall mood rating as a second dynamic factor. Further investigation may determine if these findings can simplify subjective symptom reporting in mood-monitoring studies.

Defeat, entrapment, and suicidal ideation: Twelve-month trajectories

BACKGROUND

Defeat and entrapment have been highlighted in the development of suicidal ideation within the Integrated Motivational-Volitional model of suicidal behavior. Research suggests that entrapment has to be differentiated into internal and external entrapment. The aim of this study was to investigate the associations between defeat, internal, external entrapment, and suicidal ideation within and prospectively over measurements.

METHODS

A sample of 308 psychiatric inpatients (53% female) aged 18 to 81 years (M = 36.92, SD = 14.30) was assessed for the four constructs after admission to a psychiatric ward and six, nine, and twelve months later. Multilevel analyses were conducted to examine associations.

RESULTS

Defeat was associated with (a change in) internal and external entrapment. Defeat predicted a change in internal entrapment over time. Defeat and internal, but not external, entrapment were associated with (a change in) suicidal ideation. Internal entrapment was able to predict suicidal ideation. Internal entrapment and defeat predicted a change in suicidal ideation over time.

CONCLUSION

Results highlight the importance to distinguish between internal and external entrapment, and their specific association with suicidal ideation. Perceptions of internal entrapment are of central relevance when experiencing suicidal ideation and should be considered in clinical practice.

Investigating the day-to-day impact of hypoglycaemia in adults with type 1 or type 2 diabetes: design and validation protocol of the Hypo-METRICS application

INTRODUCTION

Hypoglycaemia is a frequent adverse event and major barrier for achieving optimal blood glucose levels in people with type 1 or type 2 diabetes using insulin. The Hypo-RESOLVE (Hypoglycaemia-Redefining SOLutions for better liVEs) consortium aims to further our understanding of the day-to-day impact of hypoglycaemia. The Hypo-METRICS (Hypoglycaemia-MEasurement, ThResholds and ImpaCtS) application (app) is a novel app for smartphones. This app is developed as part of the Hypo-RESOLVE project, using ecological momentary assessment methods that will minimise recall bias and allow for robust investigation of the day-to-day impact of hypoglycaemia. In this paper, the development and planned psychometric analyses of the app are described.

METHODS AND ANALYSIS

The three phases of development of the Hypo-METRICS app are: (1) establish a working group-comprising diabetologists, psychologists and people with diabetes-to define the problem and identify relevant areas of daily functioning; (2) develop app items, with user-testing, and implement into the app platform; and (3) plan a large-scale, multicountry study including interviews with users and psychometric validation. The app includes 7 modules (29 unique items) assessing: self-report of hypoglycaemic episodes (during the day and night, respectively), sleep quality, well-being/cognitive function, social interactions, fear of hypoglycaemia/hyperglycaemia and work/productivity. The app is designed for use within three fixed time intervals per day (morning, afternoon and evening). The first version was released mid-2020 for use (in conjunction with continuous glucose monitoring and activity tracking) in the Hypo-METRICS study; an international observational longitudinal study. As part of this study, semistructured user-experience interviews and psychometric analyses will be conducted.

ETHICS AND DISSEMINATION

Use of the novel Hypo-METRICS app in a multicountry clinical study has received ethical approval in each of the five countries involved (Oxford B Research Ethics Committee, CMO Region Arnhem-Nijmegen, Ethikkommission der Medizinischen Universität Graz, Videnskabsetisk Komite for Region Hovedstaden and the Comite Die Protection Des Personnes SUD Mediterranne IV). The results from the study will be published in peer review journals and presented at national and international conferences.

TRIAL REGISTRATION NUMBER

NCT04304963.

Listen to Your Heart-Ecological Momentary Assessment of Interoceptive Accuracy, Awareness and Sensibility: A Pilot Study

Background: Interoception is a multi-facetted phenomenon including interoceptive accuracy, awareness and sensibility. Deficits in interoception have been associated with psychological distress. However, little is known about the course of interoception over time. The present study aimed at examining interoception in an ecological momentary assessment (EMA)-setting. Methods: A seven-day smartphone-based EMA was conducted in a community sample of sixty-one participants (age: M = 24.1, SD = 7.00, n = 54 female (88.5%)). To control for potential practice effects of repeated assessments during the EMA phase, participants were randomly assigned to a control (n = 30) and an interoception (n = 31) group. The latter was assessed for interoceptive accuracy, awareness and sensibility. Before and after the EMA phase, all participants were assessed for interoception in the laboratory. Results: Multilevel analyses revealed significant fluctuations for all three interoceptive facets, around 50% of variance was due to within-person variability. There were only practice effects for the subscale "Attention Regulation", measuring interoceptive sensibility. Conclusion: The facets of interoception can be assessed in an EMA-setting. Repeated interoceptive assessments do not necessarily lead to an improvement of participants' interoceptive abilities. It could be shown that all interoceptive facets fluctuate, which should be considered in future research.

Complexity of information processing in obsessive-compulsive disorder based on fractal analysis of EEG signal

The human brain is considered as a self-organizing system with self-similarities at various temporal and spatial scales called "fractals". In this scale-free system, it is possible to decode the complexity of information processing using fractal behavior. For instance, the complexity of information processing in the brain can be evaluated by fractal dimensions (FDs). However, it is unclear how over-elaboration of information processing impacts the dimensionality of its fractal behavior. In this study, we hypothesized that FDs of electroencephalogram (EEG) in obsessive-compulsive disorder (OCD) should be higher than healthy controls (HCs) because of exaggeration of information processing mainly in the frontal regions. Therefore, a group of 39 OCDs (age: 34.76±8.22, 25 female, 3 left-handed) and 19 HCs (age: 31.94±8.22, 11 female, 1 left-handed) were recruited and their brain activities were recorded using a 19-channel EEG recorder in the eyes-open resting-state condition. Subsequently, fractal dimensions of the cleaned EEG data were calculated using Katz's method in a frequency band-specific manner. After the test of normality, significant changes in the OCDs as compared to the HCs were calculated using a two-sample t-test. OCDs showed higher FDs in the frontal regions in all frequency bands as compared to HCs. Although, significant increases were only observed in the beta and lower gamma bands, mainly at the high beta. Interestingly, neurophysiological findings also show association with severity of obsessive behaviors. The results demonstrate that complexity of information processing in the brain follows an intimate nature of structural and functional impairments of the brain in OCD.

Do Feelings of Defeat and Entrapment Change over Time? An Investigation of the Integrated Motivational-Volitional Model of Suicidal Behaviour Using Ecological Momentary Assessments

(1) Background. Defeat and entrapment have been highlighted as major risk factors of suicidal ideation and behavior. Nevertheless, little is known about their short-term variability and their longitudinal association in real-time. Therefore, this study aims to investigate whether defeat and entrapment change over time and whether defeat predicts entrapment as stated by the integrated motivational-volitional model of suicidal behavior. (2) Methods. Healthy participants (n = 61) underwent a 7-day smartphone-based ecological momentary assessment (EMA) on suicidal ideation/behavior and relevant risk factors, including defeat and entrapment and a comprehensive baseline (T0) and post (T2) assessment. (3) Results. Mean squared successive differences (MSSD) and intraclass correlations (ICC) support the temporal instability as well as within-person variability of defeat and entrapment. Multilevel analyses revealed that during EMA, defeat was positively associated with entrapment at the same measurement. However, defeat could not predict entrapment to the next measurement (approximately two hours later). (4) Conclusion. This study provides evidence on the short-term variability of defeat and entrapment highlighting that repeated measurement of defeat and entrapment-preferably in real time-is necessary in order to adequately capture the actual empirical relations of these variables and not to overlook significant within-person variability. Further research-especially within clinical samples-seems warranted.

(In)stability of Capability for Suicide in Psychiatric Inpatients: Longitudinal Assessment Using Ecological Momentary Assessments

OBJECTIVE

The study examines the temporal stability of capability for suicide (i.e., its state-like component), because it has been recently discussed that capability for suicide may be subject to shift over time.

METHOD

Seventy-four psychiatric inpatients with an unipolar depressive disorder were included in the study (mean age 37.9 years, 71.6% female, 32.4% with a history of suicide attempt). After a baseline assessment with several self-report questionnaires, ecological momentary assessments were applied over six consecutive days using smartphones. Capability for suicide was rated with three items once a day. For daily capability for suicide, descriptive and variability statistics and associations with baseline clinical characteristics (depression, suicidal ideation, childhood maltreatment, and history of suicide attempt) were analyzed. The prospective association of daily level of active suicidal ideation and daily capability was investigated by multilevel analysis.

RESULTS

Indicators of within-person variability and temporal instability supported considerable fluctuation in daily capability for suicide. Yet the degree of temporal instability showed individual differences. Baseline and daily suicidal ideation were positively associated with daily fearlessness about death and perceived capability.

CONCLUSION

The results provide first evidence that capability for suicide includes a dynamic short-term component that is linked to clinical variables such as suicidal ideation.

Emotion dysregulation as a dynamic process

In this article we adopt the view that emotion dysregulation is characterized by emotion regulation dynamics that are defined as dysfunctional based on contextual criteria. We regard the construct of emotion regulation as valuable because it permits the integration of the classic view of emotions as interfering with human functioning and contemporary views of emotion as adaptive and beneficial. To define patterns that reflect emotion dysregulation, we explain our views of emotion as a dynamic process, and emotion regulation as the bidirectional interplay between emotions and actions/thoughts (extrinsic factors) and the contextual factors that constitute the criteria for that interplay reflecting dysregulation. This conceptualization of emotion regulation and dysregulation leads to methods for studying the intrinsic dynamics of emotion, extrinsic factors that change the intrinsic dynamics of emotion, and how emotion regulation changes over time at multiple time scales. We then apply this thinking to several emotion dysregulation patterns. Emotion regulation is a complex construct, embracing emotion as regulator and as regulated, as self- and other-regulated, and as incorporating both top-down and bottom-up regulatory processes. We highlight an emerging line of research on the development of emotion regulation in early childhood and indicate how this work can inform understanding of emotion dysregulation and the emergence of psychopathology.

Predicting suicidal ideation by interpersonal variables, hopelessness and depression in real-time. An ecological momentary assessment study in psychiatric inpatients with depression

OBJECTIVE

To extend evidence on the short-term variability of passive and active suicidal ideation (SI) and the association with suggested proximal risk factors such as interpersonal variables (perceived burdensomeness [PB], thwarted belongingness [TB], hopelessness, and depression) in real-time.

METHODS

This is an observational study using a prospective design applying ecological momentary assessments (EMA). Eligible for study inclusion were inpatients with unipolar depression, current or lifetime suicidal ideation, and fluent German. Over six days, 74 participants rated their momentary level of passive and active SI, PB, TB, depressiveness, and hopelessness up to 10 times per day on smartphones. Data was collected from August 2015 to July 2017. Compliance was excellent (89.7%).

RESULTS

Mean squared successive differences supported temporal instability for all variables. According intra-class correlations, between 25% and 47% of variance was accounted for by within-person variability. Multilevel analysis demonstrated significant positive associations between hopelessness, depressiveness, PB, and TB with passive SI. Prospectively, hopelessness and PB remained predictors of passive SI. For active SI, hopelessness, depression, PB, and TB were significantly associated cross-sectionally. Prospectively, hopelessness, PB, and the interaction PBxTB predicted active SI. All models were controlled for previous level of SI.

CONCLUSIONS

This study provides further evidence on the short-term variability of SI in very short time frames implying the need of assessing SI repeatedly in clinical and research settings. The associations between interpersonal variables and passive and active SI were only partial in line with assumptions of the Interpersonal Theory of Suicide. Overall, the effects were small warranting further investigation.

Affective instability across the lifespan in borderline personality disorder - a cross-sectional e-diary study

OBJECTIVE

Longitudinal and cross-sectional studies suggest that affective instability is inversely related to greater age in borderline personality disorder (BPD). However, existing studies relied on retrospective self-reports of perceived instability. We examined affective instability in everyday life in patients with BPD and healthy controls (HCs) by age in a cross-sectional e-diary study.

METHODS

Two hundred and sixty female participants between 14 and 53 years of age (130 patients with BPD and 130 HCs) carried an e-diary over 4 days. The e-diaries emitted a prompting signal in approximately hourly intervals asking participants to rate their current affective state, that is valence (ranging from pleasant to unpleasant) and tense arousal (ranging from calm/relaxed to restless/under tension).

RESULTS

Multilevel analyses revealed a significant interaction of age and group predicting affective instability (valence: F_(1,255.6)  = 7.59; P < 0.01; tense arousal: F_(1,252)  = 6.08; P < 0.01), suggesting that affective instability significantly declines with greater age in patients with BPD. Controlling for the number of comorbid disorders and BPD severity did not change the results, illustrating an inverse relationship between age and affective instability in BPD (significant interaction of age*group for valence: F_(1,238.7)  = 5.74; P < 0.02 and tense arousal: F_(1,235.2)  = 5.28; P < 0.02).

CONCLUSION

Affective instability during daily life declines with greater age in BPD. This decline is irrespective of comorbidity and BPD severity.

Heart rate variability in patients with bipolar disorder: From mania to euthymia

Bipolar Disorder (BD) is characterized by the occurrence of mania alternating with euthymia. The aim of the present study was to investigate the impact of BD on the autonomic nervous system, as indicated by heart rate variability (HRV). The study was registered in the Clinical Trials Registration (NCT01272518). Nineteen hospitalized, male patients (age: 34.0 ± 12.3 years) with type I BD were assessed during mania and at discharge on euthymia. HRV data were collected during 20- minutes in supine position at rest, on spontaneous breathing, using the Polar RS 800 CX frequencymeter. HRV measures included variables in time, frequency and non-linear domains. Psychiatric conditions were evaluated by the Mini International Neuropsychiatric Interview (MINI) and the Bech-Rafaelsen mania scale (BRMS). Time domain measures of RMSSD (Cohen's d = 0.668) and pNN50 (Cohen's d = 0.688) increased from first to second assessments. The high-frequency component (HFms2) also increased (Cohen's d = 0.586), while the LF/HF ratio decreased (Cohen's d = 0.785). Non-linear domain measures including the SD1 component (Cohen's d = 0.668), and the SD1/SD2 ratio (Cohen's d = 1.2934) extracted from the Poincare plot analysis increased from first to second assessment. The variables Lmean (Cohen's d = 0.9627), Lmax (Cohen's d = 1.2164), REC% (Cohen's d = 1.0595) and EntShannon (Cohen's d = 1.0607) were higher in mania. By contrast, ApEn (Cohen's d = 0.995) and EntSample (Cohen's d = 1.189) were less during mania, all reflecting ANS improvement. Findings are interpreted in the context of recently published models relating to neurovisceral integration across the continuum of time, and the implications for the future health and wellbeing of patients are considered.

Affect-based profiles of bulimia nervosa: The utility and validity of indicators assessed in the natural environment

Theoretical conceptualizations of bulimia nervosa (BN) emphasize the role of emotion dysregulation in the development and maintenance of symptoms, which has been supported by ecological momentary assessment studies. Given the importance of affective disturbances in BN, this study aimed to classify a sample of adult women with BN (N = 130) based on primarily momentary affective indicators, including negative and positive affect, negative and positive affective lability, and depression. Participants completed baseline assessments followed by a two-week ecological momentary assessment protocol. Latent profile analysis revealed four groups: (1) a "stable normal" group characterized by low affective lability and intensity; (2) a "stable depressed" group characterized by low affective lability and higher affect intensity; (3) an "unstable normal" group characterized by higher affective lability but lower affect intensity; and (4) an "unstable depressed" group characterized by higher affective lability and intensity. The stable depressed group evidenced the highest levels of eating psychopathology, borderline personality traits, and childhood trauma history, while the stable normal group generally evidenced the lowest levels of psychopathology. The findings demonstrate significant heterogeneity in the topography of affect experienced by individuals with BN, and suggest that chronic, intense negative affect may be particularly important to address in treatment.

State and trait positive and negative affectivity in relation to restraint intention and binge eating among adults with obesity

Restraint and binge eating are cognitive and behavioral processes that are particularly important in the context of obesity. While extensive research has focused on negative affect (NA) in relation to binge eating, it is unclear whether affective valence (i.e., positive versus negative) and stability (i.e., state versus trait) differentially predict binge eating and restraint among individuals with obesity. Distinguishing between valence and stability helps elucidate under which affective contexts, and among which individuals, restraint and binge eating are likely to occur. Therefore, the present study examined relationships between trait and state levels of NA and positive affect (PA), binge eating, and restraint intention among 50 adults with obesity (BMI ≥ 30). Participants completed baseline assessments followed by a two-week ecological momentary assessment (EMA) protocol. Structural equation modeling assessed a trait model of person-level measures of affect in relation to overall levels of binge eating and restraint intention, while general estimating equations (GEEs) assessed state models examining relationships between momentary affect and subsequent binge eating and restraint. The trait model indicated higher overall NA was related to more binge eating episodes, but was unrelated to overall restraint intention. Higher overall PA was related to higher overall restraint intention, but was unrelated to binge eating. State models indicated momentary NA was associated with a greater likelihood of subsequent binge eating and lower restraint intention. Momentary PA was unrelated to subsequent binge eating or restraint intention. Together, findings demonstrate important distinctions between the valence and stability of affect in relationship to binge eating and restraint intention among individuals with obesity. While NA is a more salient predictor of binge eating than PA, both overall PA and momentary NA are predictors of restraint intention.

The neural basis of emotions varies over time: different regions go with onset- and offset-bound processes underlying emotion intensity

According to theories of emotion dynamics, emotions unfold across two phases in which different types of processes come to the fore: emotion onset and emotion offset. Differences in onset-bound processes are reflected by the degree of explosiveness or steepness of the response at onset, and differences in offset-bound processes by the degree of accumulation or intensification of the subsequent response. Whether onset- and offset-bound processes have distinctive neural correlates and, hence, whether the neural basis of emotions varies over time, still remains unknown. In the present fMRI study, we address this question using a recently developed paradigm that allows to disentangle explosiveness and accumulation. Thirty-one participants were exposed to neutral and negative social feedback, and asked to reflect on its contents. Emotional intensity while reading and thinking about the feedback was measured with an intensity profile tracking approach. Using non-negative matrix factorization, the resulting profile data were decomposed in explosiveness and accumulation components, which were subsequently entered as continuous regressors of the BOLD response. It was found that the neural basis of emotion intensity shifts as emotions unfold over time with emotion explosiveness and accumulation having distinctive neural correlates.

Investigating the Dynamics of Suicidal Ideation

BACKGROUND

Although the fluctuating nature of suicidal ideation (SI) has been described previously, longitudinal studies investigating the dynamics of SI are scarce.

AIM

To demonstrate the fluctuation of SI across 6 days and up to 60 measurement points using smartphone-based ecological momentary assessments (EMA).

METHOD

Twenty inpatients with unipolar depression and current and/or lifetime suicidal ideation rated their momentary SI 10 times per day over a 6-day period. Mean squared successive difference (MSSD) was calculated as a measure of variability. Correlations of MSSD with severity of depression, number of previous depressive episodes, and history of suicidal behavior were examined.

RESULTS

Individual trajectories of SI are shown to illustrate fluctuation. MSSD values ranged from 0.2 to 21.7. No significant correlations of MSSD with several clinical parameters were found, but there are hints of associations between fluctuation of SI and severity of depression and suicidality.

LIMITATIONS

Main limitation of this study is the small sample size leading to low power and probably missing potential effects. Further research with larger samples is necessary to shed light on the dynamics of SI.

CONCLUSION

The results illustrate the dynamic nature and the diversity of trajectories of SI across 6 days in psychiatric inpatients with unipolar depression. Prediction of the fluctuation of SI might be of high clinical relevance. Further research using EMA and sophisticated analyses with larger samples is necessary to shed light on the dynamics of SI.

Mood and motor activity in euthymic bipolar disorder with sleep disturbance

BACKGROUND

The aims of this observational study of patients with euthymic bipolar disorder and sleep disturbance were to 1) compare characteristics related to mood and sleep between two groups with stable and unstable rest-activity cycles and 2) detect between-group differences in motor activity patterns.

METHODS

43 patients wore an actigraph for 6-8 days while reporting daily mood and sleep. Patients were defined as having an unstable rest-activity cycle if their diurnal active period duration presented variation above 2h from the mean during one week: 22 patients had stable and 21 unstable rest-activity cycles. Mood variability was defined as at least moderate symptoms and a change across two levels on a 7-point mood scale during one week.

RESULTS

Patients with unstable rest-activity cycles were younger (37 vs. 48 years, p=0.01) and displayed more mood variability (p=0.02). Ten of 11 patients diagnosed with delayed sleep phase disorder were in the unstable group (p<0.01), and the unstable group had later and more variable get-up-times and bedtimes. In actigraphy recordings, the mean activity counts per minute did not differ between groups, but the minute-to-minute variability was elevated (p=0.04) and increased relative to the overall variability (p=0.03).

LIMITATIONS

A relatively small study sample and a 1-week study period prevent exploration of long-term clinical implications of results.

CONCLUSIONS

A subgroup of euthymic patients with bipolar disorder displayed unstable rest-activity cycles combined with mood variability and motor activity patterns that resemble findings in affective episodes.

Linear and non-linear analyses of Conner's Continuous Performance Test-II discriminate adult patients with attention deficit hyperactivity disorder from patients with mood and anxiety disorders

BACKGROUND

Attention Deficit Hyperactivity Disorder (ADHD) is a heterogeneous disorder. Therefore it is important to look for factors that can contribute to better diagnosis and classification of these patients. The aims of the study were to characterize adult psychiatric out-patients with a mixture of mood, anxiety and attentional problems using an objective neuropsychological test of attention combined with an assessment of mood instability.

METHOD

Newly referred patients (n = 99; aged 18-65 years) requiring diagnostic evaluation of ADHD, mood or anxiety disorders were recruited, and were given a comprehensive diagnostic evaluation including the self-report form of the cyclothymic temperament scale and Conner's Continuous Performance Test II (CPT-II). In addition to the traditional measures from this test we have extracted raw data and analysed time series using linear and non-linear mathematical methods.

RESULTS

Fifty patients fulfilled criteria for ADHD, while 49 did not, and were given other psychiatric diagnoses (clinical controls). When compared to the clinical controls the ADHD patients had more omission and commission errors, and higher reaction time variability. Analyses of response times showed higher values for skewness in the ADHD patients, and lower values for sample entropy and symbolic dynamics. Among the ADHD patients 59 % fulfilled criteria for a cyclothymic temperament, and this group had higher reaction time variability and lower scores on complexity than the group without this temperament.

CONCLUSION

The CPT-II is a useful instrument in the assessment of ADHD in adult patients. Additional information from this test was obtained by analyzing response times using linear and non-linear methods, and this showed that ADHD patients with a cyclothymic temperament were different from those without this temperament.

Examining affect and perfectionism in relation to eating disorder symptoms among women with anorexia nervosa

This study examined personality and affective variables in relation to eating disorder symptoms in anorexia nervosa (AN). Women (N=118) with DSM-IV AN completed baseline questionnaires (Beck Depression Inventory, Frost Multidimensional Perfectionism Scale) and interviews (Eating Disorder Examination, Yale-Brown-Cornell Eating Disorder Scale), followed by two weeks of ecological momentary assessment (EMA) involving multiple daily reports of affective states and eating disorder behaviors. Hierarchical regression analyses were conducted using eating disorder symptoms as dependent variables (i.e., EMA binge eating, EMA self-induced vomiting, eating disorder rituals, eating disorder preoccupations, dietary restraint). Predictor variables were maladaptive perfectionism (baseline), depressive symptoms (baseline), and affect lability (EMA). Results revealed that affect lability was independently associated with binge eating, whereas depressive symptoms were independently associated with self-induced vomiting. Depressive symptoms were independently associated with eating disorder rituals, whereas both depressive symptoms and maladaptive perfectionism were independently associated with eating disorder preoccupations. Finally, maladaptive perfectionism and affect lability were both independently associated with dietary restraint. This pattern of findings suggests the importance of affective and personality constructs in relation to eating disorder symptoms in AN and may highlight the importance of targeting these variables in the context of treatment.

Models for the Study of Whole Systems

This article summarizes a network and complex systems science model for research on whole systems of complementary and alternative medicine (CAM) such as homeopathy and traditional Chinese medicine. The holistic concepts of networks and nonlinear dynamical complex systems are well matched to the global and interactive perspectives of whole systems of CAM, whereas the reductionistic science model is well matched to the isolated local organ, cell, and molecular mechanistic perspectives of pharmaceutically based biomedicine. Whole systems of CAM are not drugs with specific actions. The diagnostic and therapeutic approaches of whole systems of CAM produce effects that involve global and patterned shifts across multiple subsystems of the person as a whole. For homeopathy, several characteristics of complex systems, including the probabilistic nature of attractor patterns, variable sensitivity of complex systems to initial conditions, and emergent behaviors in the evolution of a system in its full environmental context over time, could help account for the mixed basic science and controlled clinical trial research findings, in contrast with the consistently positive outcomes of observational studies in the literature. Application of theories and methods from complex systems and network science can open a new era of advances in understanding factors that lead to good versus poor individual global outcome patterns and to rational triage of patients to one type of care over another. The growing reliance on complex systems thinking and systems biology for cancer research affords a unique opportunity to bridge between the CAM and conventional medical worlds with some common language and conceptual models.

Motor Activity in Adult Patients with Attention Deficit Hyperactivity Disorder

OBJECTIVE

Hyperactivity is a core symptom of attention-deficit hyperactivity disorder (ADHD), but limited information is available on analysis of activity patterns in this disorder. The aim of the study was to analyze motor activity during daily living in adult patients with ADHD.

METHODS

Patients (n=76) from the private psychiatric practice of two of the authors were recruited, and were compared to patients with other psychiatric disorders and to normal controls. Actigraphs were used to record motor activity for six days, with one minute intervals, and data were analysed using linear and non-linear mathematical methods.

RESULTS

For short recording periods (300 minutes) the activity levels of ADHD patients do not differ from normal controls, but the autocorrelation (lag 1) is lower and Fourier analysis shows higher power in the high frequency range, corresponding to the period from 2-8 min. During recordings for six days there are no significant differences between ADHD patients and the control groups. The combined and inattentive subgroups differ only in the six days recordings. The Fourier analyses show that the combined type has lower power in the high frequency range, corresponding to the period from 4-8 hours, and in the analysis of rhythms the intra-daily variability is lower, compared to the inattentive type.

CONCLUSION

Adult ADHD patients do not show evidence of hyperactivity, but have levels of activity similar to normal controls. However, on several measures ADHD patients display altered activity patterns, indicating that the regulation of motor activity in this disorder is different from controls.

Initial test of an emotional avoidance model of restriction in anorexia nervosa using ecological momentary assessment

It has been hypothesized that restrictive eating allows individuals with anorexia nervosa (AN) to avoid contact with negative emotions; however, this presumption has not been directly tested. In this study, we conducted an initial investigation examining whether restrictive eating serves an emotional avoidance function among individuals with AN. Females with AN (n = 118) reported on negative and positive affect, anxiety/tension, and eating behaviors at multiple time points daily over a 2-week period using ecological momentary assessment methodology. Affective patterns were compared using generalized estimating equation models between days in which participants reported either: (1) relatively high restriction (without binge eating); (2) relatively low restriction (without binge eating); (3) binge eating; or (4) no restriction or binge eating. We hypothesized that, if restriction were functioning to avoid negative affect, average negative affect and anxiety/tension, as well as average negative and positive affect lability, would be lower and average positive affect would be higher on days characterized by high levels of restriction compared to other eating patterns. Contrary to hypotheses: (1) average negative affect, anxiety/tension, and positive affect were not significantly different between days characterized by high restriction and those characterized by low or no restriction; (2) Negative affect and anxiety/tension lability were higher on days characterized by high restriction compared to no restriction or binge eating days; (3) Anxiety/tension lability was higher on days characterized by high versus low levels of restriction. This patterns of findings does not support an avoidance model of restrictive eating for individuals with AN.

[To err is human? Interests of chaotic models to study adult psychiatric disorders and developmental disorders]

BACKGROUND

Many clinical and biological parameters have nonlinear chaotic fluctuations. These variations result in unexpected pseudo-random transitions. In these models, few risk factors can lead to unexpected phenomena if oscillations and self-reinforcement patterns occur. Complex rhythms could ease the ability of a physiological system to adapt and react quickly to a constantly changing environment.

OBJECTIVES

It has been proposed that several psychiatric disorders and developmental disorders are characterized by a loss of complex rhythm in favor of a more organized pattern. We examine evidence to support these assumptions in literatures.

METHODS

We performed a literature review of the main computerized databases (Medline, PubMed) and manual searches of the literature concerning non dynamic rhythms in time series analysis, in adults with psychiatric disorder and children with developmental disorder. These results were interpreted through a developmental approach that highlights the role of the learning process in the emergence of abilities.

RESULTS

Analysis of clinical scores and electroencephalographic data have found that subjects with bipolar disorder or schizophrenia, tested over a time series, have lower chaotic rhythms compared with healthy subjects. Growing children share several properties of a complex system: the interdependence of developmental axes (motor, emotional, language, social skills), multiple hierarchical levels (i.e. genetic, biological, environmental, and cultural), the two-way transactions between the child and his environment, and the sensitivity to initial conditions. This could explain the difficulty to predict the emergence of abilities or the long-term prognosis of impairment in children. This limitation is not only due to errors in the explanatory model or the lack of explanatory variable. It is also caused by instability, which is a core characteristic of a chaotic system.

CONCLUSION

The study of chaotic rhythms in time-series clinical and nonclinical data (e.g. EEG, functional neuroimaging) could improve the prediction of an acute event, such as relapse of mood disorder. Moreover, the complex rhythms in children may play a major part in synchronicity during interactions with a caregiver, held as essential for later development of self-regulation skills, such as emotional stability.

Specificity of affective instability in patients with borderline personality disorder compared to posttraumatic stress disorder, bulimia nervosa, and healthy controls

Affective instability is a core feature of borderline personality disorder (BPD). The use of advanced assessment methodologies and appropriate statistical analyses has led to consistent findings that indicate a heightened instability in patients with BPD compared with healthy controls. However, few studies have investigated the specificity of affective instability among patients with BPD with regard to relevant clinical control groups. In this study, 43 patients with BPD, 28 patients with posttraumatic stress disorder (PTSD), 20 patients with bulimia nervosa (BN), and 28 healthy controls carried e-diaries for 24 hours and were prompted to rate their momentary affective states approximately every 15 minutes while awake. To quantify instability, we used 3 state-of-the-art indices: multilevel models for squared successive differences (SSDs), multilevel models for probability of acute changes (PACs), and aggregated point-by-point changes (APPCs). Patients with BPD displayed heightened affective instability for emotional valence and distress compared with healthy controls, regardless of the specific instability indices. These results directly replicate earlier studies. However, affective instability did not seem to be specific to patients with BPD. With regard to SSDs, PACs, and APPCs, patients with PTSD or BN showed a similar heightened instability of affect (emotional valence and distress) to that of patients with BPD. Our results give raise to the discussion if affective instability is a transdiagnostic or a disorder-specific mechanism. Current evidence cannot answer this question, but investigating psychopathological mechanisms in everyday life across disorders is a promising approach to enhance validity and specificity of mental health diagnoses.

Ecological momentary assessment in borderline personality disorder: a review of recent findings and methodological challenges

The use of Ecological Momentary Assessment (EMA) has led to increased insight into borderline personality disorder (BPD) symptoms, especially regarding affective instability. EMA is characterized by a series of repeated assessments of current affective, behavioral, and contextual experiences or physiological processes while participants engage in normal daily activities. EMA has several advantages. It enables researchers to avoid biased recollection, to investigate within-person processes, and to enhance real-life generalizability. This review is dedicated to four main objectives: (1) to discuss the characteristics of EMA in studying BPD symptomatology; (2) to provide an extensive overview of EMA findings in BPD structured into findings regarding DSM-IV criteria and findings regarding emotional dysregulation as stated in the biosocial theory of Linehan; (3) to discuss challenges of EMA and to give recommendations for the proper use of it; and (4) to highlight prospects and promising applications that should be addressed.

How is affective instability defined and measured? A systematic review

BACKGROUND

Affective instability (AI) is poorly defined but considered clinically important. The aim of this study was to examine definitions and measures of AI employed in clinical populations.

METHOD

This study was a systematic review using the PRISMA guidelines. MEDLINE, Embase, PsycINFO, PsycArticles and Web of Science databases were searched. Also five journals were hand searched. Primary empirical studies involving randomized controlled trials (RCTs), non-RCTs, controlled before and after, and observational investigations were included. Studies were selected, data extracted and quality appraised. A narrative synthesis was completed.

RESULTS

A total of 11 443 abstracts were screened and 37 studies selected for final analysis on the basis that they provided a definition and measure of AI. Numbers of definitions for each of the terms employed in included studies were: AI (n = 7), affective lability (n = 6), affective dysregulation (n = 1), emotional dysregulation (n = 4), emotion regulation (n = 2), emotional lability (n = 1), mood instability (n = 2), mood lability (n = 1) and mood swings (n = 1); however, these concepts showed considerable overlap in features. A total of 24 distinct measures were identified that could be categorized as primarily measuring one of four facets of AI (oscillation, intensity, ability to regulate and affect change triggered by environment) or as measuring general emotional regulation.

CONCLUSIONS

A clearer definition of AI is required. We propose AI be defined as 'rapid oscillations of intense affect, with a difficulty in regulating these oscillations or their behavioural consequences'. No single measure comprehensively assesses AI and a combination of current measures is required for assessment. A new short measure of AI that is reliable and validated against external criteria is needed.

Emotional and behavioral dyscontrol after traumatic brain injury

Emotional and behavioral dyscontrol are relatively common neuropsychiatric sequelae of traumatic brain injury and present substantial challenges to recovery and community participation. Among the most problematic and functionally disruptive of these types of behaviors are pathologic laughing and crying, affective lability, irritability, disinhibition, and aggression. Managing these problems effectively requires an understanding of their phenomenology, epidemiology, and clinical evaluation. This article reviews these issues and provides clinicians with brief and practical suggestions for the management of emotional and behavioral dyscontrol.

Associations between retrospective versus ecological momentary assessment measures of emotion and eating disorder symptoms in anorexia nervosa

This study examined the unique associations between eating disorder symptoms and two emotion-related constructs (affective lability and anxiousness) assessed via distinct methodologies in anorexia nervosa (AN). Women (N = 116) with full or subthreshold AN completed baseline emotion and eating disorder assessments, followed by two weeks of ecological momentary assessment (EMA). Hierarchical regressions were used to examine unique contributions of baseline and EMA measures of affective lability and anxiousness in accounting for variance in baseline eating disorder symptoms and EMA dietary restriction, controlling for age, body mass index, depression, and AN diagnostic subtype. Only EMA affective lability was uniquely associated with baseline eating disorder symptoms and EMA dietary restriction. Anxiousness was uniquely associated with baseline eating disorder symptoms regardless of assessment method; neither of the anxiousness measures was uniquely associated with EMA dietary restriction. Affective lability and anxiousness account for variance in global eating disorder symptomatology; AN treatments targeting these emotion-related constructs may prove useful.

Chaos in Human Behavior: The Case of Work Motivation

This study considers the complex dynamics of work motivation. Forty-eight employees completed a work-motivation diary several times per day over a period of four weeks. The obtained time series were analysed using different methodologies derived from chaos theory (i.e. recurrence plots, Lyapunov exponents, correlation dimension and surrogate data). Results showed chaotic dynamics in 75% of cases. The findings confirm the universality of chaotic behavior within human behavior, challenge some of the underlying assumptions on which work motivation theories are based, and suggest that chaos theory may offer useful and relevant information on how this process is managed within organizations.

Methodological implications of nonlinear dynamical systems models for whole systems of complementary and alternative medicine

This paper focuses on the worldview hypotheses and research design approaches from nonlinear dynamical complex systems (NDS) science that can inform future studies of whole systems of complementary and alternative medicine (WS-CAM), e.g., Ayurveda, traditional Chinese medicine, and homeopathy. The worldview hypotheses that underlie NDS and WS-CAM (contextual, organismic, interactive-integrative - Pepper, 1942) overlap with each other, but differ fundamentally from those of biomedicine (formistic, mechanistic). Differing views on the nature of causality itself lead to different types of study designs. Biomedical efficacy studies assume a simple direct mechanistic cause-effect relationship between a specific intervention and a specific bodily outcome, an assumption less relevant to WS-CAM outcomes. WS-CAM practitioners do not necessarily treat a symptom directly. Rather, they intervene to modulate an intrinsic central imbalance of the person as a system and to create a more favorable environmental context for the emergence of health, e.g., with dietary changes compatible with the constitutional type. The rebalancing of the system thereby fosters the emergence of indirect, diffuse, complex effects throughout the person and the person's interactions with his/her environment. NDS theory-driven study designs thus have the potential for greater external and model validity than biomedically driven efficacy studies (e.g., clinical trials) for evaluating the indirect effects of WS-CAM practices. Potential applications of NDS analytic techniques to WS-CAM include characterizing different constitutional types and documenting the evolution and dynamics of whole-person healing and well-being over time. Furthermore, NDS provides models and methods for examining interactions across organizational scales, from genomic/proteomic/metabolomic networks to individuals and social groups.

Short-term effects of repeated olfactory administration of homeopathic sulphur or pulsatilla on electroencephalographic alpha power in healthy young adults

INTRODUCTION

Homeopathic pathogenetic trials usually rely on symptom self report measures. Adding objective biomarkers could enhance detection of subtle initial remedy effects. The present feasibility study examined electroencephalographic (EEG) effects of repeated olfactory administration of two polycrest remedies.

METHODS

College student volunteers (ages 18-30, both sexes) from an introductory psychology course were screened for good health and relatively elevated Sulphur or Pulsatilla symptom scores on the Homeopathic Constitutional Type Questionnaire (CTQ). Subjects underwent a series of 3 once-weekly double-blind sessions during which they repeatedly sniffed the remedy matched to their CTQ type and solvent controls. Each remedy was given in a 6c, 12c, and 30c potency, one potency per week, in randomly assigned order. Solvent controls included both plain distilled water and a water-ethanol (95%) solution. All sniff test solutions were further diluted just prior to laboratory sessions (0.5 ml test solution in 150 ml distilled water). Within a session, remedies and control solvents were administered via 2-s sniffs (8 sniffs of each of 4 different succussion levels for the potency in randomized order). Primary outcome variable was relative EEG power (alpha 1 8-10 Hz; alpha 2 10-12 Hz) averaged over 19 electrode sites, including all succussions for a given potency.

RESULTS

Mixed-effect models revealed significant main effects for remedy type (Sulphur >Pulsatilla) in both alpha bands, controlling for gender, baseline resting EEG alpha, and solvent control responses. Additional analyses showed significant nonlinear interactions between dilution and time (weekly session) in alpha 2 for both remedies and alpha 1 for Sulphur.

CONCLUSION

EEG alpha offers an objective biomarker of remedy effects for future studies and potential method for distinguishing time-dependent effects of specific remedies and remedy potencies from one another.

Affective variability predicts suicidal ideation in individuals at ultra-high risk of developing psychosis: an experience sampling study

OBJECTIVE

There is a suggestion in the literature that more variable affect increases suicidal ideation through the repeated re-activation of latent suicidal cognitions. The hypothesis that affective variability would be a better predictor of suicidal ideation and related behaviour than affect level was tested in individuals at ultra-high risk of developing psychosis. This study also examined the prediction that affective variability is a suicide-specific mechanism and would not predict levels of attenuated psychotic phenomena.

METHOD

Twenty-seven ultra-high risk individuals were required to complete ambulant ratings of their affect when prompted by an electronic wristwatch for six days (the experience sampling method). In the debriefing session, participants were assessed with a semi-structured interview (the Comprehensive Assessment of At-Risk Mental State), which assessed the severity and frequency of suicidality and psychosis-related phenomena.

RESULTS

The variability of negative and positive affect was predictive of the frequency of suicidal thoughts and behaviour. More variable negative, but not positive affect, was also associated with more severe suicidal ideation and related behaviour. Affect variability was not significantly related to the severity of attenuated psychotic phenomena.

CONCLUSION

Affective variability appears to be a specific risk factor for suicidal ideation in individuals at ultra-high risk of developing psychosis. Early intervention should focus on providing individuals with skills for regulating their own affect.

Nonlinear analysis of motor activity shows differences between schizophrenia and depression: a study using Fourier analysis and sample entropy

The purpose of this study has been to describe motor activity data obtained by using wrist-worn actigraphs in patients with schizophrenia and major depression by the use of linear and non-linear methods of analysis. Different time frames were investigated, i.e., activity counts measured every minute for up to five hours and activity counts made hourly for up to two weeks. The results show that motor activity was lower in the schizophrenic patients and in patients with major depression, compared to controls. Using one minute intervals the depressed patients had a higher standard deviation (SD) compared to both the schizophrenic patients and the controls. The ratio between the root mean square successive differences (RMSSD) and SD was higher in the schizophrenic patients compared to controls. The Fourier analysis of the activity counts measured every minute showed that the relation between variance in the low and the high frequency range was lower in the schizophrenic patients compared to the controls. The sample entropy was higher in the schizophrenic patients compared to controls in the time series from the activity counts made every minute. The main conclusions of the study are that schizophrenic and depressive patients have distinctly different profiles of motor activity and that the results differ according to period length analysed.

Instability of physical anxiety symptoms in daily life of patients with panic disorder and patients with posttraumatic stress disorder

The present study examined severity as well as degree and temporal pattern of instability of DSM-IV-based bodily symptoms of anxiety (BSA) in daily life of 26 panic disorder (PD) patients, 17 posttraumatic stress disorder (PTSD) patients, and 28 healthy controls (HC) during 1 week, using electronic diaries. The ecological momentary assessment around every 3h during wake times was accepted well by patients. Compared to HC, patient groups exhibited elevated instability of BSA. BSA instability was more pronounced in PTSD than PD (p<0.005), even after controlling for mean symptom level. Numbers of symptomatic episodes were comparable in PTSD and PD, but the duration of symptom-free episodes was shorter in PTSD than PD. Results indicate that PTSD patients are particularly burdened by fluctuations in somatic symptoms of anxiety, implying perceived unpredictability and uncontrollability. Electronic diaries can be applied in innovative ways to provide novel insights into the phenomenology of anxiety disorders that may not be captured well by retrospective interviews and questionnaires.

Variability in nucleus accumbens activity mediates age-related suboptimal financial risk taking

As human life expectancy continues to rise, financial decisions of aging investors may have an increasing impact on the global economy. In this study, we examined age differences in financial decisions across the adult life span by combining functional neuroimaging with a dynamic financial investment task. During the task, older adults made more suboptimal choices than younger adults when choosing risky assets. This age-related effect was mediated by a neural measure of temporal variability in nucleus accumbens activity. These findings reveal a novel neural mechanism by which aging may disrupt rational financial choice.

A comparison of retrospective self-report versus ecological momentary assessment measures of affective lability in the examination of its relationship with bulimic symptomatology

Affective lability has been linked to several maladaptive behaviors (Anestis et al., 2009; Coccaro, 1991). Methodology for measuring affective lability varies and includes retrospective self-report and ecological momentary assessment (EMA). In this study, we sought to test these methodologies by examining which better predicted binge eating episodes and general eating disorder symptoms in a sample (n = 131) of women diagnosed with bulimia nervosa (BN). We hypothesized that, while the two forms of measurement would be correlated with one another and predict binge eating episodes, EMA affective lability would be the stronger predictor. Results supported several hypotheses. Specifically, both EMA affective lability and retrospective self-report affective lability significantly predicted global eating disorder symptoms, even when controlling for depression, age, body mass index, and level of education, EMA affective lability exhibited a significantly stronger correlation with binge eating episodes than did retrospective self-report affective lability, and EMA affective lability predicted number of binge eating episodes on any given day controlling for the same list of covariates. Limitations include the use of a clinical sample that may limit the generalizability of our findings. Findings highlight the importance of affect in such behavior.

The phenomenology of bipolar disorder: what drives the high rate of medical burden and determines long-term prognosis?

Bipolar disorder (BD) has been classically described as one of episodic mood disturbances. New evidence suggests that a chronic course and multisystem involvement is the rule, rather than the exception, and that together with disturbances of circadian rhythms, mood instability, cognitive impairment, a high rate of medical burden is often observed. The current diagnostic approach for BD neither describes the multisystem involvement that the recent literature has highlighted nor points toward potential predictors of long- term outcome. In light of the new evidence that the long-term course of BD is associated with a high prevalence of psychiatric comorbidity and an increased mortality from medical disease, we propose a multidimensional approach that includes several symptom domains, namely affective instability, circadian rhythm dysregulation, and cognitive and executive dysfunction, presenting in various combinations that give shape to each individual presentation, and offers potential indicators of overall long-term prognosis.

Distress and affective dysregulation in patients with borderline personality disorder: a psychophysiological ambulatory monitoring study

Borderline personality disorder (BPD) is characterized by enduring psychological distress and affective dysregulation. Several models have linked both phenomena, but are lacking empirical support. To investigate the relation between psychological distress and components of affective dysregulation (especially inability to label emotions, conflictive emotions, and physiological hyperarousal), we repeatedly assessed these components using a 24-hour ambulatory monitoring approach in a group of 50 BPD patients and 50 healthy controls. Hierarchical linear model analyses identified a clear relation between inability to label emotions and distress in the BPD group (p = 0.0009) but not across all subjects (p = 0.6492). Conflictive emotions were related to psychological distress in both groups (p < 0.0001). This relation is, however, most pertinent to the BPD group who experienced conflicting emotions more frequently. Physiological arousal (heart rate) was related to distress in both groups. Our empirical findings emphasize training in labeling emotions and distress tolerance interventions in treatment for BPD.

Six-month prospective life charting of mood symptoms with lamotrigine monotherapy versus placebo in rapid cycling bipolar disorder

BACKGROUND

Fluctuations in mood are quintessential features of bipolar disorder; however, previous studies have seldom examined the extent to which pharmacotherapies for bipolar disorder may reduce or ameliorate daily or weekly mood variability. The anticonvulsant lamotrigine has demonstrated efficacy for relapse prevention in bipolar disorder, but its possible mood-stabilizing properties on a day-to-day or week-to-week basis have not previously been investigated.

METHODS

Weekly mood shifts were examined over 26 weeks using patients' self-reported prospective Life Chart Method (LCM) data obtained as part of a previously reported randomized relapse prevention comparison of lamotrigine monotherapy or placebo in 182 bipolar patients with DSM-IV rapid cycling. Generalized estimating equation (GEE) analyses were used to compare treatment arms for subjects who achieved euthymia across weeks.

RESULTS

After adjusting for potential confounding factors, a final GEE model revealed that subjects taking lamotrigine were 1.8 times more likely than those taking placebo to achieve euthymia, as measured by LCM, at least once per week over 6 months (95% confidence interval [CI] = 1.03-3.13). Subjects taking lamotrigine had an increase of .69 more days per week euthymic as compared with those taking placebo (p = .014).

CONCLUSIONS

Achievement of euthymia across weeks represents a novel paradigm shift in gauging the mood-stabilizing properties of a psychotropic agent. The present findings demonstrate the utility of the prospective Life Chart Method for assessing longitudinal mood stability during randomized clinical trials for bipolar disorder. The results lend support to the potential mood-stabilizing properties of lamotrigine monotherapy for bipolar disorder.

Ambulatory Assessment of Affective Instability in Borderline Personality Disorder

Abstract. Affective instability is an essential criterion for borderline personality disorder (BPD) but studies using diaries have rendered conflicting results. Discrepant findings may be caused by differences in the time-based design, especially in the diverse length of the time intervals between self-reports. Even though there is consensus that the time-based design should fit the temporal dynamics of the processes of interest, no general conventions exist. We used 24 h ambulatory monitoring to repeatedly assess subjective ratings of distress in 50 BPD-patients and in 50 healthy controls. We investigated if the chosen time-based design with a time interval of 15 min between self-reports (1) reveals within subject variability in BPD-patients and (2) taps the process of interest. Using graphical and statistical evaluation, we demonstrate that the time-based design (15 min/24 h) does catch within-person variability in the BPD-patients. Comparison of the original data with randomly distributed data (simulation) and autocorrelation analyses prove that we tapped a specific process and did not randomly pick states of distress. Using increasing lags between self-reports reveals that short intervals, especially, (15 min, 30 min) tap a specific process. We recommend using short time intervals to study temporal dynamics of affective instability.

Fragile self-esteem and affective instability in posttraumatic stress disorder

Temporal fluctuations in self-esteem and affect are prominent features of several clinical conditions (e.g., depression), but there is an absence of empirical work examining their role in posttraumatic stress disorder (PTSD). Individuals who experience large fluctuations in self-evaluations and affect are considered more vulnerable to psychopathology than individuals able to adequately modulate their self-image and emotional responses. We examined the relevance of self-esteem and affective instability to PTSD. Veterans with and without PTSD completed 14 daily ratings of self-esteem, positive affect, negative affect, and gratitude. Compared to veterans without PTSD, veterans with PTSD exhibited more temporal fluctuations in self-esteem, negative affect, and gratitude, with a smaller effect for positive affect. For all veterans, self-esteem and negative affective instability was associated with diminished well-being. Except for self-esteem instability, most findings were substantially reduced after accounting for variance attributable to PTSD diagnoses and mean intensity levels over the 14-day monitoring period. These data suggest self-esteem instability is important in understanding the lives of veterans with and without PTSD.

A novel technique to evaluate fluctuations of mood: implications for evaluating course and treatment effects in bipolar/affective disorders

OBJECTIVES

Several psychiatric conditions are associated with frequent fluctuations of affect. In this study, we propose a new technique to uniformly score depression and mania objectively and use a new mathematical technique to model the frequent fluctuations in mood using simulated data. Our main aim is to examine the usefulness of this measure for evaluating treatment effects or course of illness, especially in bipolar or unipolar affective illness to quantify mood fluctuations.

METHODS

We use a prototypical model, which takes into account the mean, the standard deviation (SD) and the coefficient of variation (CV = SD*100/mean) of the mood scores of the subjects over a user-defined period. We utilize simulated data of subjects for euthymia, minor depression, minor mania, severe depression, severe mania and cyclic bipolar illness (manic depression, MDP). We propose an objective method to quantify the mood of the subjects at weekly intervals (the interval can be user-defined) using a scale of 1-9 (1-4 = degrees of depression, 5 = euthymia, 6-9 = degrees of mania). These scores can be sampled according to the convenience and feasibility of the measurements, which can be derived from various clinical scales or by observation of the subjects in hospitals or other environments. We derive a new mathematical technique to arrive at a normalized measure for each of these conditions of simulated data in addition to the mean, SD and approximate entropy (ApEn).

RESULTS

We utilize three sets of data, one to train the model to classify the condition of the subjects and the other two to test the reliability of the technique. We are able to successfully classify the condition of the subjects over a 52-timepoint period (length can be days or weeks depending upon the sampling rate). The New Index (NI) correlates significantly only with the mean (r(2) = 0.78), but not with the SD or ApEn score.

CONCLUSIONS

These results indicate that it may be beneficial to reduce data according to the techniques we propose so that there is greater uniformity within which to compare future studies to evaluate treatment effects, not only in rapid-cycling MDP but also in other affective disorders. This method may be suitable for the meta-analysis of several studies, although different scales have been used in each of those studies. Our measure derived from simulated data has shown sufficient deviation of all the abnormal states from the euthymic state. The advantages and pitfalls of these techniques are further discussed to evaluate affect in various disorders. However, future prospective studies must address the importance of this measure in comparison with mean, SD and ApEn scores or other nonlinear measures of these time series. We are evaluating other nonlinear dynamic models, which may provide a continuous measure with which to identify different degrees of fluctuation of mood.

Naturalistic evaluation of suicidal ideation: Variability and relation to attempt status

Suicidal ideation has been thought to have a relatively stable course across weeks and months. However, daily changes in levels of ideation have not been adequately examined despite the importance of potential variability clinically and conceptually. For example, it has been suggested that variability in suicidal ideation may become less closely tied to variability in other mood symptoms (e.g., depression, hopelessness) among individuals with multiple suicide attempts. The present report had two related goals: (1) to prospectively evaluate suicidal ideation and related mood symptoms, and (2) to determine whether suicide attempt status predicted a decreased association between ideation and other mood symptoms. Non-clinical participants (N=108) with varying levels of suicidal ideation and number of previous suicide attempts completed the beck hopelessness scale (BHS), beck depression inventory (BDI), and suicide probability scale (SPS) every day for 4 weeks. Findings suggested considerable variability in suicidal ideation, especially for multiple attempters. Multiple attempt status predicted a decreased association between suicidal ideation and depression, although the results were only marginally significant. These findings have implications for conceptual models of suicide risk as well as assessment and treatment of suicidal individuals.