Weekly links among irritability and suicidal thoughts and behaviors in high-risk youth.

BACKGROUND: Previous studies demonstrate a link between irritability and suicidal thoughts and behaviors (STBs) in youth samples. However, they have mostly assessed irritability in community samples and as a largely dispositional (i.e. trait-like) construct. Thus, it remains unclear to what extent links between irritability and STBs reflect within-person processes of elevated risk in clinically meaningful time periods. METHODS: The present study used clinical data from 689 adolescents aged 12-19 years attending a total of 6,128 visits at a specialty Intensive Outpatient Program for depressed and suicidal youth to examine patterns in weekly assessments of irritability and STBs throughout treatment, including associations among trends and fluctuations departing from these trends via multilevel structural equation modeling. Youth completed self-report measures of irritability, depression, and STBs weekly as part of standard IOP clinical care. RESULTS: Overall, two-thirds of variance in weekly irritable mood was accounted for by between-person differences and the remaining portion by weekly fluctuations. After controlling for depression, during weeks when youth were more irritable they experienced increased STBs. Rates of change in irritability and STBs tended to track together at early stages of treatment, but these effects were generally accounted for by depression severity. CONCLUSIONS: Our results suggest that although changes in STBs are best accounted for by depression, irritability can be understood as a specific, proximal risk factor for youth STBs that exacerbates youth STBs in clinically informative timeframes above and beyond depression.

Neuroticism is Associated With Greater Affective Variability at High Levels of Momentary Affective Well-Being, but With Lower Affective Variability at Low Levels of Momentary Affective Well-Being.

OBJECTIVE: Research challenged the notion that neuroticism correlates with affective variability, suggesting that it may result from statistical artifacts due to the non-normal distribution of negative affect. We aim to advance this line of research by (a) introducing affect balance as a normally distributed measure of affective well-being and (b) examining current affect balance as a moderator of the relationship between neuroticism and affect balance variability. METHOD: We meta-analyzed the results of 14 ambulatory assessment datasets (N = 2389 participants, N = 174,423 observations). RESULTS: We found that while the associations between the mean and affective variability were large for negative affect, they were much smaller for affect balance. Moreover, the association between neuroticism and variability in negative affect was very small, yet medium-sized for affect balance. Importantly, the latter association depended on current affect levels: Participants high relative to low in neuroticism showed stronger subsequent fluctuations in affect balance when currently feeling better than usual, but weaker subsequent fluctuations in (and thus more persistent) affect balance when currently feeling worse than usual. CONCLUSION: Increased variability should not be seen as a bad sign but may be a sign that an affective system is changing, which may be adaptive or maladaptive for an individual, depending on the initial state of the system.

Considering the 'With Whom': Differences Between Event- and Signal-Contingent ESM Data of Person-Specific Social Interactions.

Experience sampling studies often aim to capture social interactions. A central methodological question in such studies is whether to use event- or signal-contingent sampling. The little existing research on this issue has not taken into account that social interactions occur with unique interaction partners (e.g., Anna or Tom). We analyze one week of social interaction data of 286 students from the University of Pittsburgh (60.8% male, mean age 19.2 years), taking into account the unique interaction partners of each student. Specifically, we investigate the differences between event- and signal contingent sampling in (1) the total number of unique interaction partners captured, as well as (2) the kinds of relationships, and (3) the quality of social interactions with these captured interaction partners. Apart from a larger quantity of interactions and unique interaction partners in the event-contingent sampling design, our analyses indicate subtle differences between the two designs when aiming to assess social interactions with more distant interaction partners, such as coworkers or strangers. Most importantly, in our analyses, specific interaction partners and social roles explained a considerable amount of variance in the quality of social interactions (up to 20.5%), suggesting that future research would benefit greatly from considering "with whom" individuals interact.

The Structure of Identity Dysfunction in Self-Report Measures.

Identity dysfunction is considered core to psychopathology, contributing to emotional and interpersonal problems across psychiatric diagnoses. Despite its centrality in theories of personality and psychopathology, the empirical research on the structure of identity dysfunction is fragmented by a plethora of self-report measures assessing varied domains of identity dysfunction. This project examines conceptual domains of identity dysfunction in self-report assessments, with the goal of elucidating a clear structure of identity dysfunction to advance both theory and measurement. Toward this aim, we a) investigate the factor structure of identity dysfunction in existing self-report measures, using exploratory factor analysis and b) examine relationships between identity dysfunction and closely related constructs, using exploratory structural equation modeling. We assess responses from 632 young adults to 17 commonly used identity functioning self-report measures. In a series of exploratory factor analyses, we identified four content-domains of Identity Dysfunction (Self-Alienation, Susceptibility to External Influence, Self-Dysregulation, and Contingent Self-Esteem) and three content domains of Identity Clarity (Self-Consistency, Reflective Functioning, and Authentic Living). These content domains were largely well-represented by a single factor. In a series of exploratory structural equation models, emergent factors related similarly to personality, emotion dysregulation, and values and problems in interpersonal relationships.

Mindfulness-Based Stress Reduction reduces pro-inflammatory gene regulation but not systemic inflammation among older adults: A randomized controlled trial.

OBJECTIVE: Aging is associated with increased pro-inflammatory gene expression and systemic inflammation, and psychosocial stress may accelerate these changes. Mindfulness interventions show promise for reducing psychosocial stress and extending healthspan. Inflammatory pathways may play a role. In a sample of lonely older adults, we tested whether mindfulness training reduces proinflammatory gene expression and protein markers of systemic inflammation. METHODS: Lonely older adults (65-85 years; N = 190) were randomly assigned to an 8-week Mindfulness-Based Stress Reduction (MBSR) or matched Health Enhancement Program (HEP). Blood was drawn pre- and post-intervention and at 3-month follow-up. In peripheral blood mononuclear cells (PBMCs), RNA profiling was used to assess transcriptional regulation by pro-inflammatory NF-kB as well as ß-adrenergic CREB, antiviral IRF, and glucocorticoid receptor (GR) transcription factors. Plasma was assayed for proinflammatory markers IL-6 and CRP. Analyses tested time (pre, post, follow-up) by condition (MBSR versus HEP) effects. RESULTS: MBSR reduced NF-kB (d = .17, p = .028) but did not alter CREB (d = .10, p = .20), IRF (d = .13, p = .086), or GR activity (d = .14, p = .063) relative to HEP over time. Contrary to predictions, there were no time × condition effects of MBSR compared to HEP on reducing circulating IL-6 or CRP. CONCLUSIONS: In lonely older adults, MBSR reduced cellular pro-inflammatory gene regulation in ways that would predict reduced disease risk. However, no similar effect was observed for circulating protein markers of inflammation. These results provide specificity about how mindfulness interventions may impact distinct inflammatory markers among aging adults in ways that may have important implications for healthspan. TRIAL REGISTRATION: Clinical Trials identifier NCT02888600.

Meta-analysis of structural evidence for the Hierarchical Taxonomy of Psychopathology (HiTOP) model.

BACKGROUND: The Hierarchical Taxonomy of Psychopathology (HiTOP) is a classification system that seeks to organize psychopathology using quantitative evidence - yet the current model was established by narrative review. This meta-analysis provides a quantitative synthesis of literature on transdiagnostic dimensions of psychopathology to evaluate the validity of the HiTOP framework. METHODS: Published studies estimating factor-analytic models from diagnostic and statistical manual of mental disorders (DSM) diagnoses were screened. A total of 120,596 participants from 35 studies assessing 23 DSM diagnoses were included in the meta-analytic models. Data were pooled into a meta-analytic correlation matrix using a random effects model. Exploratory factor analyses were conducted using the pooled correlation matrix. A hierarchical structure was estimated by extracting one to five factors representing levels of the HiTOP framework, then calculating congruence coefficients between factors at sequential levels. RESULTS: Five transdiagnostic dimensions fit the DSM diagnoses well (comparative fit index = 0.92, root mean square error of approximation = 0.07, and standardized root-mean-square residual = 0.03). Most diagnoses had factor loadings >|0.30| on the expected factors, and congruence coefficients between factors indicated a hierarchical structure consistent with the HiTOP framework. CONCLUSIONS: A model closely resembling the HiTOP framework fit the data well and placement of DSM diagnoses within transdiagnostic dimensions were largely confirmed, supporting it as valid structure for conceptualizing and organizing psychopathology. Results also suggest transdiagnostic research should (1) use traits, narrow symptoms, and dimensional measures of psychopathology instead of DSM diagnoses, (2) assess a broader array of constructs, and (3) increase focus on understudied pathologies.

Systemic Inflammation Contributes to the Association Between Childhood Socioeconomic Disadvantage and Midlife Cardiometabolic Risk.

BACKGROUND: Childhood socioeconomic disadvantage is associated with increased risk for chronic inflammation and cardiometabolic disease at midlife. PURPOSE: As it is presently unknown whether inflammation mediates the relationship between childhood socioeconomic status (SES) and adulthood cardiometabolic risk, we investigated associations between retrospectively reported childhood SES, circulating levels of inflammatory markers, and a latent construct of cardiometabolic risk in midlife adults. METHODS: Participants were 1,359 healthy adults aged 30-54 (Adult Health and Behavior Iⅈ 52% women, 17% Black) who retrospectively reported childhood SES (parental education, occupational grade). Measures included plasma interleukin (IL)-6, C-reactive protein (CRP), and cardiometabolic risk factors. Structural equation modeling was conducted, with cardiometabolic risk modeled as a second-order latent variable with adiposity, blood lipids, glucose control, and blood pressure as first-order components. RESULTS: Lower childhood SES was associated with greater risk for cardiometabolic disease at midlife (ß = -0.08, CI[-0.04, -0.01], p = .01) in models adjusted for demographics, but this association was attenuated in models that adjusted for adulthood SES and health behaviors. In fully-adjusted models, the relationship between lower childhood SES and adult cardiometabolic risk was partially explained by higher circulating levels of CRP (ß = -0.05, CI[-0.02, -0.01], p = .001), but not by IL-6. In an exploratory model, lower adulthood SES was also found to independently contribute to the association between childhood SES and adult cardiometabolic risk (ß = -0.02, CI[-0.01, -0.001], p = .02). CONCLUSIONS: The current study provides initial evidence that systemic inflammation may contribute to childhood socioeconomic disparities in cardiometabolic risk in midlife. Future work would benefit from prospective investigation of these relationships.

The personality meta-trait of stability and carotid artery atherosclerosis.

BACKGROUND: Several personality traits increase the risk for atherosclerotic cardiovascular disease. Because many of these traits are correlated, their associations with disease risk could reflect shared variance, rather than unique contributions of each trait. We examined a higher-order personality trait of Stability as related to preclinical atherosclerosis and tested whether any such relationship might be explained by correlated variation in cardiometabolic risk factors. METHOD: Among 798 community volunteers, lower-order traits of Neuroticism, Agreeableness, and Conscientiousness were modeled as latent variables (from self- and informant ratings) and used to estimate the second-order factor, Stability. Cardiometabolic risk was similarly modeled from indicators of glycemic control, blood pressure, adiposity, and lipids. Carotid artery atherosclerosis was measured as intima-media thickness (IMT) by duplex ultrasonography. RESULT: A structural equation model incorporating direct and indirect effects showed lower Stability associated with greater IMT, and this relationship was accounted for by the indirect pathway via cardiometabolic risk. Secondary analyses showed that: (1) Neuroticism, Agreeableness, and Conscientiousness were unrelated to IMT independent of Stability; and (2) Stability predicted variation in IMT when estimated from informant-, but not self-rated, traits. CONCLUSION: Personality traits may associate with atherosclerotic burden through their shared, rather than unique, variance, as reflected in Stability.

Momentary interpersonal processes of suicidal surges in borderline personality disorder.

BACKGROUND: Suicide rates are high in borderline personality disorder (BPD) where interpersonal problems trigger intense affective dysregulation and impulses to act on suicidal thoughts. To date, however, no study has examined how interpersonal stressors contribute to momentary within-person links among affect and impulsivity with suicidal ideation (SI), and how those links vary over time in people's daily lives. METHODS: A total of 153 individuals diagnosed with BPD and 52 healthy controls completed a 21-day ecological momentary assessment protocol. Of these 153 individuals with BPD, 105 had a history of suicide attempts. Multilevel structural equation modeling was used to examine dynamic links among interpersonal perceptions, affect, state impulsivity, and suicidal intent. RESULTS: Aggregated across interactions, lower perceived warmth in others was associated with SI. This direct relationship, however, did not extend to momentary within-person associations. Instead, interpersonal conflicts were linked to SI indirectly via greater negative affect and lower positive affect. While a robust within-person link between interpersonal perceptions and impulsivity emerged, impulsivity did not account for the relationship between interpersonal perceptions and SI. CONCLUSION: This intensive longitudinal study illustrates momentary interpersonal signatures of an emerging suicidal crisis. Among people with BPD at high risk for suicide, interpersonal triggers initiate a cascade of affective dysregulation, which in turn gives rise to SI.

The Hierarchical Taxonomy of Psychopathology (HiTOP) in psychiatric practice and research.

The Hierarchical Taxonomy of Psychopathology (HiTOP) has emerged out of the quantitative approach to psychiatric nosology. This approach identifies psychopathology constructs based on patterns of co-variation among signs and symptoms. The initial HiTOP model, which was published in 2017, is based on a large literature that spans decades of research. HiTOP is a living model that undergoes revision as new data become available. Here we discuss advantages and practical considerations of using this system in psychiatric practice and research. We especially highlight limitations of HiTOP and ongoing efforts to address them. We describe differences and similarities between HiTOP and existing diagnostic systems. Next, we review the types of evidence that informed development of HiTOP, including populations in which it has been studied and data on its validity. The paper also describes how HiTOP can facilitate research on genetic and environmental causes of psychopathology as well as the search for neurobiologic mechanisms and novel treatments. Furthermore, we consider implications for public health programs and prevention of mental disorders. We also review data on clinical utility and illustrate clinical application of HiTOP. Importantly, the model is based on measures and practices that are already used widely in clinical settings. HiTOP offers a way to organize and formalize these techniques. This model already can contribute to progress in psychiatry and complement traditional nosologies. Moreover, HiTOP seeks to facilitate research on linkages between phenotypes and biological processes, which may enable construction of a system that encompasses both biomarkers and precise clinical description.

Mindfulness-based stress reduction increases stimulated IL-6 production among lonely older adults: A randomized controlled trial.

Loneliness is a potent psychosocial stressor that predicts poor health and mortality among older adults, possibly in part by accelerating age-related declines in immunocompetence. Mindfulness interventions have shown promise for reducing loneliness and improving markers of physical health. In a sample of lonely older adults, this two-arm parallel trial tested whether mindfulness training enhances stimulated interleukin-6 (IL-6) production, a measure of innate immune responsivity. Lonely older adults (65-85 years; N = 190) were randomized to an 8-week Mindfulness-Based Stress Reduction (MBSR) or control Health Enhancement Program (HEP) intervention. Lipopolysaccharide (LPS)-stimulated production of IL-6 was measured in vitro by blinded outcome assessors at pre-intervention, post-intervention, and 3-month follow-up. Mixed-effects linear models tested time (pre, post, follow-up) by condition (MBSR vs. HEP) effects. As predicted, a significant time × condition effect on stimulated IL-6 production was observed across pre, post, and follow-up timepoints. Significant MBSR vs. HEP differences emerged from pre- to post-intervention (p =.009, d = 0.38) and from pre-intervention to 3-month follow-up (p =.017, d = 0.35), with larger increases in IL-6 production following MBSR compared to HEP. No study-related adverse events were reported. Results show that mindfulness training may be effective for boosting innate immunocompetence among lonely older adults. Given that immunocompetence tends to decline with age, mindfulness training may help to counteract the effects of aging and psychosocial stress on infection risk and recovery from injury.

Conscientiousness and Cardiometabolic Risk: A Test of the Health Behavior Model of Personality Using Structural Equation Modeling.

BACKGROUND: High trait conscientiousness is associated with lower cardiometabolic risk, and health behaviors are a putative but relatively untested pathway that may explain this association. PURPOSE: To explore the role of key health behaviors (diet, physical activity, substance use, and sleep) as links between conscientiousness and cardiometabolic risk. METHODS: In a cross-sectional analysis of 494 healthy, middle-aged working adults (mean age = 42.7 years, 52.6% women, 81.0% White), participants provided self-reports of conscientiousness, physical activity, substance use, diet, and sleep, and wore monitors over a 7-day monitoring period to assess sleep (Actiwatch-16) and physical activity (SenseWear Pro3). Cardiometabolic risk was expressed as a second-order latent variable from a confirmatory factor analysis involving insulin resistance, dyslipidemia, obesity, and blood pressure. Direct, indirect, and specific indirect effect pathways linking conscientiousness to health behaviors and cardiometabolic risk were examined. Unstandardized indirect effects for each health behavior class were computed separately using bootstrapped samples. RESULTS: After controlling for demographics (sex, age, race, and education), conscientiousness showed the predicted, inverse association with cardiometabolic risk. Among the examined health behaviors, objectively-assessed sleep midpoint variability (b = -0.003, p = .04), subjective sleep quality (b = -0.003, p = .025), and objectively-assessed physical activity (b = -0.11, p = .04) linked conscientiousness to cardiometabolic risk. CONCLUSIONS: Physical activity and sleep partially accounted for the relationship between conscientiousness and cardiometabolic risk.

Continuous-Time Modeling of the Bidirectional Relationship Between Incidental Affect and Physical Activity.

BACKGROUND: Previous research suggests that there is a bidirectional relationship between incidental affect (i.e., how people feel in day-to-day life) and physical activity behavior. However, many inconsistencies exist in the body of work due to the lag interval between affect and physical activity measurements. PURPOSE: Using a novel continuous-time analysis paradigm, we examined the temporal specificity underlying the dynamic relationship between positive and negative incidental affective states and moderate-to-vigorous physical activity (MVPA). METHODS: A community sample of adults (n = 126, Mage = 27.71, 51.6% Male) completed a 14-day ambulatory assessment protocol measuring momentary positive and negative incidental affect six times a day while wearing a physical activity monitor (Fitbit). Hierarchical Bayesian continuous-time structural equation modeling was used to elucidate the underlying dynamics of the relationship between incidental affective states and MVPA. RESULTS: Based on the continuous-time cross-effects, positive and negative incidental affect predicted subsequent MVPA. Furthermore, engaging in MVPA predicted subsequent positive and negative incidental affect. Incidental affective states had a greater relative influence on predicting subsequent MVPA compared to the reciprocal relationship. Analysis of the discrete-time coefficients suggests that cross-lagged effects increase as the time interval between measurements increase, peaking at about 8 h between measurement occasions before beginning to dissipate. CONCLUSIONS: The results provide support for a recursive relationship between incidental affective states and MVPA, which is particularly strong at 7-9 hr time intervals. Future research designs should consider these medium-term dynamics, for both theory development and intervention.

Integrating and distinguishing personality and psychopathology.

OBJECTIVE: We asked authors of this Special Issue to answer the following four questions: (1) Is there evidence that personality and psychopathology can be integrated? (2) Is integration important? (3) Can they be distinguished? and (4) How can the difference be measured? METHOD: We review each of the papers and place the special issue in a historical context. RESULTS: Authors uniformly agreed that personality and psychopathology can be integrated within a common structure and that this is important. The third and fourth questions were more challenging. Though authors generally agreed that there is a distinction between the person and their mental health problems, articulations of that distinction were fuzzy and it is clear that current methods cannot adequately delineate these domains. CONCLUSIONS: We summarize the issue by offering five directions for future research: (1) develop measurement tools that distinguish between the person, the context, and their transaction, (2) measure behavior and context at multiple timescales, (3) distinguish behavior and dysfunction in measurement, (4) use multimethod data to tap different levels of behavior, and (5) examine person-specific processes. Each of these directions comes with challenges, but the payoff of resolving them will be a more principled, evidence-based, and clinically useful model for the distinction between personality and psychopathology.

The distinction between symptoms and traits in the Hierarchical Taxonomy of Psychopathology (HiTOP).

The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirically and quantitatively derived dimensional classification system designed to describe the features of psychopathology and, ultimately, to replace categorical nosologies. Among the constructs that HiTOP organizes are "symptom components" and "maladaptive traits," but past HiTOP publications have not fully explicated the distinction between symptoms and traits. We propose working definitions of symptoms and traits and explore challenges, exceptions, and remaining questions. Specifically, we propose that the only systematic difference between symptoms and traits in HiTOP is one of time frame. Maladaptive traits are dispositional constructs that describe persistent tendencies to manifest features of psychopathology, whereas symptoms are features of psychopathology as they are manifest during any specific time period (from moments to days to months). This has the consequence that almost every HiTOP dimension, at any level of the hierarchy, can be assessed as either a trait or a symptom dimension, by adjusting the framing of the assessment. We discuss the implications of these definitions for causal models of the relations between symptoms and traits and for distinctions between psychopathology, normal personality variation, and dysfunction.

A crisis of generalizability or a crisis of constructs?

Psychologists wish to identify and study the mechanisms and implications of nomothetic constructs that reveal truths about human nature and span across operationalizations. To achieve this goal, psychologists should spend more time carefully describing and measuring constructs across a wide range of methods and measures, and less time rushing to explain and predict.

Exploratory Machine Learning Modeling of Adaptive and Maladaptive Personality Traits from Passively Sensed Behavior.

Continuous passive sensing of daily behavior from mobile devices has the potential to identify behavioral patterns associated with different aspects of human characteristics. This paper presents novel analytic approaches to extract and understand these behavioral patterns and their impact on predicting adaptive and maladaptive personality traits. Our machine learning analysis extends previous research by showing that both adaptive and maladaptive traits are associated with passively sensed behavior providing initial evidence for the utility of this type of data to study personality and its pathology. The analysis also suggests directions for future confirmatory studies into the underlying behavior patterns that link adaptive and maladaptive variants consistent with contemporary models of personality pathology.

Mindfulness-Based Stress Reduction Buffers Glucocorticoid Resistance Among Older Adults: A Randomized Controlled Trial.

OBJECTIVE: Mindfulness interventions have been effective for improving a range of health outcomes; however, pathways underlying these effects remain unclear. Inflammatory processes may play a role, possibly through increased resistance of immune cells to the anti-inflammatory effects of glucocorticoids (i.e., glucocorticoid resistance, or GCR). Here, we conducted an initial examination of whether mindfulness training mitigates GCR among lonely older adults. METHODS: Lonely older adults (65-85 years; n = 190) were randomly assigned to an 8-week Mindfulness-Based Stress Reduction (MBSR) or a matched Health Enhancement Program (HEP). Whole blood drawn before and after the intervention and at 3-month follow-up was incubated with endotoxin and varying concentrations of dexamethasone, and interleukin-6 production was assessed using enzyme-linked immunosorbent assay. GCR was assessed as the concentration of dexamethasone required to decrease the stimulated interleukin-6 response by 50% (half maximal inhibitory concentration), with higher concentrations indicating greater GCR. Mixed-effects linear models tested time (pre, post, follow-up) by condition (MBSR versus HEP) effects. RESULTS: There was no overall time by condition effect on GCR across all time points. However, a significant time by condition effect was observed from preintervention to postintervention (d = 0.29), such that MBSR buffered increases in GCR observed in the HEP group. Although MBSR showed small, nonsignificant reductions in GCR from preintervention to 3-month follow-up, group differences were not maintained at the 3-month follow-up (d = 0.10). CONCLUSIONS: Results suggest that MBSR may protect against declines in the sensitivity of immune cells to the anti-inflammatory effects of glucocorticoids among at-risk lonely older adults and show value in studying this biological mechanism in future trials.Trial Registration: Clinical Trials identifier NCT02888600.

Day-to-day associations between sleep characteristics and affect in community dwelling adults.

Despite the high co-occurrence of sleep and mood disturbances, day-to-day associations between sleep characteristics (sleep duration, continuity, and timing) and dimensions of mood (positive affect and negative affect) remain unclear. The present study aimed to test whether there is a daily, bidirectional association between these sleep characteristics and affective states, while addressing methodological limitations in the extant literature by using actiography and ecological momentary assessment methods. Participants were community dwelling, midlife adults (aged 30-54 years, N = 462, 47% male) drawn from the Adult Health and Behavior Project-Phase 2 study. Participants' sleep patterns were assessed with actiography over a 7-day monitoring period, and on 4 of those days, participants completed an ecological momentary assessment protocol that included hourly assessments of positive affect and negative affect during their wake intervals. Using hierarchical linear modelling, we tested whether participants' sleep characteristics on a given night predicted next-day affect and vice versa. We also explored whether nocturnal sleep characteristics would differentially associate with affect at different times of day (morning, afternoon, and evening) while controlling for multiple health behaviours. We found that when participants reported higher positive affect on a given day, they slept later that night (B = 0.22, p = .010). Although we found no other statistically significant associations in our primary analyses (all p > .05), we found several sleep-affect associations specific to time of day (B ranges: 0.01-0.18, all p ≤ .02), which warrants further study. Overall, our findings suggest that healthy adults may be resilient to daily fluctuations in their sleep and mood.

The Hierarchical Taxonomy of Psychopathology (HiTOP): A Quantitative Nosology Based on Consensus of Evidence.

Traditional diagnostic systems went beyond empirical evidence on the structure of mental health. Consequently, these diagnoses do not depict psychopathology accurately, and their validity in research and utility in clinicalpractice are therefore limited. The Hierarchical Taxonomy of Psychopathology (HiTOP) consortium proposed a model based on structural evidence. It addresses problems of diagnostic heterogeneity, comorbidity, and unreliability. We review the HiTOP model, supporting evidence, and conceptualization of psychopathology in this hierarchical dimensional framework. The system is not yet comprehensive, and we describe the processes for improving and expanding it. We summarize data on the ability of HiTOP to predict and explain etiology (genetic, environmental, and neurobiological), risk factors, outcomes, and treatment response. We describe progress in the development of HiTOP-based measures and in clinical implementation of the system. Finally, we review outstanding challenges and the research agenda. HiTOP is of practical utility already, and its ongoing development will produce a transformative map of psychopathology.