Modeling the hypothalamus–pituitary–adrenal axis: A review and extension

Multiple models of the hypothalamus–pituitary–adrenal (HPA) axis have been developed to characterize the oscillations seen in the hormone concentrations and to examine HPA axis dysfunction. We reviewed the existing models, then replicated and compared five of them by finding their correspondence to a dataset consisting of ACTH and cortisol concentrations of 17 healthy individuals. We found that existing models use different feedback mechanisms, vary in the level of details and complexities, and offer inconsistent conclusions. None of the models fit the validation dataset well. Therefore, we re-calibrated the best performing model using partial calibration and extended the model by adding individual fixed effects and an exogenous circadian function. Our estimated parameters reduced the mean absolute percent error significantly and offer a validated reference model that can be used in diverse applications. Our analysis suggests that the circadian and ultradian cycles are not created endogenously by the HPA axis feedbacks, which is consistent with the recent literature on the circadian clock and HPA axis.United States. National Institutes of Health (R21MH100515

Modeling and estimating the feedback mechanisms among depression, rumination, and stressors in adolescents

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The systemic interactions among depressive symptoms, rumination, and stress are important to understanding depression but have not yet been quantified. In this article, we present a system dynamics simulation model of depression that captures the reciprocal relationships among stressors, rumination, and depression. Building on the response styles theory, this model formalizes three interdependent mechanisms: 1) Rumination contributes to 'keeping stressors alive'; 2) Rumination has a direct impact on depressive symptoms; and 3) Both 'stressors kept alive' and current depressive symptoms contribute to rumination. The strength of these mechanisms is estimated using data from 661 adolescents (353 girls and 308 boys) from two middle schools (grades 6-8). These estimates indicate that rumination contributes to depression by keeping stressors 'alive'-and the individual activated- even after the stressor has ended. This mechanism is stronger among girls than boys, increasing their vulnerability to a rumination reinforcing loop. Different profiles of depression emerge over time depending on initial levels of depressive symptoms, rumination, and stressors as well as the occurrence rate for stressors; levels of rumination and occurrence of stressors are stronger contributors to long-term depression. Our systems model is a steppingstone towards a more comprehensive understanding of depression in which reinforcing feedback mechanisms play a significant role. Future research is needed to expand this simulation model to incorporate other drivers of depression and provide a more holistic tool forstudying depression.National Institutes of Health (U.S.) (Award R21MH100515)National Institute of Mental Health (U.S.) (Award R21MH100515

2005 Rosabeth Moss Kanter Award for Excellence in Work-Family Research Publication

Over the past few decades there has been an explosion of research on the relationships between work and non-work life. Researchers studying these issues come from many disciplines and professions, resulting in fragmented awareness of one another\u27s work. In addition, exchanges of research information among scholars, consultants and corporate practitioners are limited. Many research studies are not well-grounded in theory, slowing the generation of new knowledge. As a result, it has been difficult to develop shared standards for research quality and to avoid redundance in the research literature. Some excellent studies have failed to have impact because of lack of awareness. This award raises awareness of high quality work-family research among the scholar, consultant and practitioner communities. It fosters debate about what the standards of quality for work-family research should be, and ultimately will raise those standards. And it identifies the best of the best on which to base future research. The award is named for Rosabeth Moss Kanter, who has been identified by leading scholars as the person having the most influence on the modern research literature on work and family. The proposals contained in her 1977 monograph “Work and Family in the United States: A Critical Review and Agenda for Research and Policy” remain timely almost a quarter-century later. The Kanter award is given to the authors of the best piece of work-family research published during a calendar year (note that family is defined broadly). No external nominations are accepted for the award. Instead, every article published in a large number of scientific journals is scrutinized by a large committee of esteemed scholars who generate a list of candidates for the award

The relation of depressive symptoms and marital quality of depressed and nondepressed mothers to offspring\u27s perceived attachment: A multiple-domain growth analysis

The link between maternal depression and adverse child development has been well established (Goodman & Gotlib, 1999). Depressed mothers experience significant difficulties in many domains (i.e. personal functioning, parenting, environment stress), all of which can influence the mother-child relationship and, specifically, mother-child attachment (Murray, Halligan, Adams, Petterson, & Goodyer, 2006). Marital conflict is often present in families where parental psychopathology exists (Hammen, 2002) and marital conflict repeatedly has been associated with insecure child attachment. The relation between maternal depression, marital quality, and child\u27s attachment has been primarily examined in cross-sectional samples. The present study extended prior research by investigating this relation longitudinally using a quasi-experimental design and by examining all constructs simultaneously. Growth modeling was used to examine how marital quality and depressive symptoms of depressed mothers receiving treatment and nondepressed mothers were related to child and adolescent attachment. According to results from the final model, nondepressed mothers experience less depressive symptoms and marital quality than mothers being treated for depression across 22 months. Thus, even after mothers were treated for depression, their levels of marital quality and depressive symptoms were consistently less optimal than the levels for nondepressed mothers. Additionally, offspring of nondepressed mothers experience higher attachment security than children of depressed mothers, even after the depressed mothers were treated. In essence, treating mothers\u27 depressive symptoms does not appear to improve their marital quality and mother-child attachment to the level of mothers not suffering from depression. While these findings may seem discouraging, perhaps incorporating relationship focused interventions in addition to depression treatment could produce more promising results. Future studies are needed to examine if marital and family focused, as well as depression treatment allow depressed mothers being treated and their offspring to experience similar levels of marital quality and mother-child attachment as nondepressed mothers and their children

Treating Depression in Men: The Role of Emotionally Focused Couple Therapy

While initial treatment recommendations for depression in the context of relationship problems have been outlined, attention typically has been focused on females experiencing depression. Less is known about the assessment and treatment of men with depression and relationship distress. This article presents the current literature on depression and relationship problems, including what is currently known about the occurrence, expression, assessment, and treatment of depression in men. Theoretical and empirically based assessment and treatment recommendations are then provided for Emotionally Focused Couple Therapy with depressed men in distressed relationships. © 2012 Springer Science+Business Media, LLC

Estimating the parameters of system dynamics models using indirect inference

There is limited methodological guidance for estimating system dynamics (SD) models using datasets common to social sciences that include few data points over time for many units under analysis. Here, we introduce indirect inference, a simulation-based estimation method that can be applied to common datasets and is applicable to SD models that often include intractable likelihood functions. In this method, the model parameters are found by ensuring that simulated data from the model and available empirical data produce similar auxiliary statistics. The method requires few assumptions about the structure of the model and error-generating processes and thus can be used in a variety of applications. We demonstrate the method in estimating an SD model of depression and rumination using a panel dataset. The overall results suggest that indirect inference can extend the application of SD models to new topics and leverage common panel datasets to provide unique insights

Treatment Delivery Preferences Associated With Type of Mental Disorder and Perceived Treatment Barriers Among Mexican University Students

PURPOSE: Although Internet-based electronic health (eHealth) interventions could potentially reduce mental health disparities, especially in college students in under-resourced countries, little is known about the relative acceptability of eHealth versus in-person treatment modalities and the treatment barriers associated with a preference for one type over the other. METHODS: Participants were from the 2018-2019 cohort of the University Project for Healthy Students (PUERTAS), a Web-based survey of incoming first-year students in Mexico and part of the World Mental Health International College Student Survey initiative. A total of 7,849 first-year students, 54.73% female, from five Mexican universities participated. We estimated correlates of preference for eHealth delivery over in-person modalities with a multivariate logistic regression. RESULTS: Thirty-eight percent of students prefer in-person services, 36% showed no preference for in-person over eHealth, 19% prefer not to use services of any kind, and 7% preferred eHealth over in-person treatment delivery. Being embarrassed, worried about harm to one's academic career, wanting to handle problems on one's own, beliefs about treatment efficacy, having depression, and having attention-deficient hyperactivity disorder were associated with a clear preference for eHealth delivery methods with odds ratios ranging from 1.47 to 2.59. CONCLUSIONS: Although more students preferred in-person services over eHealth, those reporting attitudinal barriers (i.e., embarrassment, stigma, wanting to handle problems on one's own, and beliefs about treatment efficacy) and with depression or attention-deficit hyperactivity disorder had a greater preference for eHealth interventions suggesting these are students to whom eHealth interventions could be targeted to alleviate symptoms and/or as a bridge to future in-person treatment.status: publishe