Evidence suggests several causes for depression, including traumatic life events, disease, poison, and nutritional deficiencies. Many of these causes are associated with elevated levels of inflammatory biomarkers in the blood, which may in turn lead to inflammatory changes in the brain. Our authors examine what the latest research reveals about the link between inflammation in the brain and depression, and how a better understanding of that link can play a critical first step in the personalization of care.
A cascade of neuroendocrine events regulates the initiation and progression of female puberty. However, the factors that determine the timing of these events across individuals are still uncertain. While the consequences of puberty on subsequent emotional development and adult behavior have received significant attention, what is less understood are the social and environmental factors that actually alter the initiation and progression of puberty. In order to more fully understand what factors influence pubertal timing in females, the present study quantified social and emotional behavior; stress physiology; and growth and activity measures in juvenile female rhesus monkeys to determine what best predicts eventual puberty. Based on previous reports, we hypothesized that increased agonistic behavior resulting from subordinate status in their natal group, in combination with slowed growth, reduced prosocial behavior, and increased emotional reactivity would predict delayed puberty. The analyses were restricted to behavioral and physiological measures obtained prior to the onset of puberty, defined as menarche. Together, our findings indicate that higher rates of aggression but lower rates of submission received from group mates; slower weight gain; and greater emotional reactivity, evidenced by higher anxiety, distress and appeasing behaviors, and lower cortisol responsivity in response to a potentially threatening situation, predicts delayed puberty. Together the combination of these variables accounted for 58% of the variance in the age of menarche, 71% in age at first ovulation, and 45% in the duration of adolescent sterility. While early puberty may be more advantageous for the individual from a fertility standpoint, it presents significant health risks, including increased risk for a number of estrogen dependent cancers and as well as the emergence of mood disorders during adulthood. On the other hand, it is possible that increased emotional reactivity associated with delayed puberty could persist, increasing the risk for emotional dysregulation to socially challenging situations. The data argue for prospective studies that will determine how emotional reactivity shown to be important for pubertal timing is affected by early social experience and temperament, and how these stress-related variables contribute to body weight accumulation, affecting the neuroendocrine regulation of puberty.
Implicit intergroup bias emerges early in development, are typically pro-ingroup, and remain stable across the lifespan. Such findings have been interpreted in terms of an automatic ingroup bias similar to what is observed with minimal groups paradigms. These studies are typically conducted with groups of high cultural standing (e.g., Caucasians in North America and Europe). Research conducted among culturally lower status groups (e.g., African-Americans, Latino-Americans) reveals a notable absence of an implicit ingroup bias. Understanding the environmental factors that contribute to the absence of an implicit ingroup bias among people from culturally lower status groups is critical for advancing theories of implicit intergroup cognition. The present study aimed to elucidate the factors that shape racial group bias among African-American children and young adults by examining their relationship with age, school composition (predominantly Black schools or racially mixed schools), parental racial attitudes and socialization messages among African-American children (N = 86) and young adults (N = 130). Age, school-type and parents’ racial socialization messages were all found to be related to the strength of pro-Black (ingroup) bias. We also found that relationships between implicit and explicit bias and frequency of parents' racial socialization messages depended on the type of school participants attended. Our results highlight the importance of considering environmental factors in shaping the magnitude and direction of implicit and explicit race bias among African-Americans rather than treating them as a monolithic group.
Despite widespread assumptions that psychopathy is associated with serious and repeated law-breaking, individuals with psychopathic personality traits do not invariably become chronic criminal offenders. As a partial explanation for this finding, Lykken (1995) ventured that a fearless temperament underlies both psychopathic traits and heroic behavior, and that heroic individuals’ early exposure to effective socializing forces such as warm parenting or healthy self-esteem often fosters a characteristic adaption that tends to beget “successful” behaviors, thereby differentiating heroes from convicts. In this study, we investigate relations between psychopathy, principally its fearless dominance dimension, pride, and prosocial and antisocial behavior in a community sample (N = 339). Fearless dominance and self-centered impulsivity components of psychopathy yielded differential relations with authentic and hubristic pride (Tracy and Robins, 2004), such that fearless dominance was significantly positively correlated with both facets of pride while self-centered Impulsivity was significantly negatively correlated with authentic pride and significantly positively correlated with hubristic pride. Further, authentic pride moderated (potentiated) the relation between fearless dominance and transformational leadership, one of the two outcome measures for prosocial behavior employed in our investigation. Authentic pride did not moderate the relations between fearless dominance and either our other measure of prosocial behavior (heroism) or antisocial behavior, nor did positive parenting moderate the relations between psychopathy components and social behavior. Unexpectedly, hubristic pride significantly moderated the relation between impulsive-antisocial features and antisocial behavior in a protective manner.
Background Incidence of community acquired pneumonia is high globally. In Bangladesh, more male children than female children are brought to hospitals for pneumonia. We examined if there was disparities in the severity of illness and outcome by sex among children who were admitted with pneumonia to hospitals in Bangladesh. Methods Hospitalized children, aged 2 to 59 months, meeting a case definition of pneumonia were recruited in seven hospitals following parental consent. At baseline, study doctors obtained socio-demographic characteristics and care seeking behaviors for pneumonia, and then clinical data were collected throughout the hospital stay. Multivariate analysis was performed to determine if the sex of the child had a relationship with either illness severity on admission or outcome in the hospital. Results Between May 2004 and December 2008, 6,856 children, including 35% females, were recruited. A total of 1,371 (19.9%) children had non-severe pneumonia, 4,118 (60.0%) had severe pneumonia, and 1,367 (19.9%) had very severe pneumonia. A higher proportion of hospitalized females had very severe pneumonia as compared to males (21.5% versus 19.1%; P = 0.01), but there was no difference by sex in the proportion of children with severe or non-severe pneumonia. There was no difference by sex observed in the clinical management provided in the hospital, but a greater proportion of females (4.7%) as compared to males (3.6%) died in hospitals (P = 0.04). In multivariate analyses, female sex was associated with very severe pneumonia on admission (OR: 1.26, 95% CI: 1.09–1.47) and fatal outcome in the hospitals (OR: 1.31, 95% CI: 1.01–1.71). Death in female children admitted with very severe pneumonia was 4 times higher than that reported in males (OR: 4.37, 95% CI: 3.24–5.89). Conclusion Our data demonstrates a sex-based disparity in the severity of pneumonia and deaths among children admitted to hospitals in Bangladesh, despite no existing disparity by sex in hospital treatment. These findings call for further investigations to explore the determinants of health seeking behavior by parents with children with pneumonia in a community that favors males to females, and to understand the role of differences by sex in childhood pneumonia outcomes in Bangladesh.
by
Mark Tomlinson;
Mary Jane Rotheram-Borus;
Ingrid M. le Roux;
Maryann Youssef;
Sandahl H. Nelson;
Aaron Scheffler;
Robert E. Weiss;
Mary O’Connor;
Carol Worthman
Almost all pregnant women (98%) in 24 Cape Town neighborhoods were randomized by neighborhood to: 1) the standard care (SC) condition (n=12 neighborhoods; n=594 pregnant women), or 2) the Philani Intervention Program (PIP) in which home visits by Community Health Workers (CHW) were conducted (n=12 neighborhoods; n=644 pregnant women). At 36 months post-birth (84.6% follow-up) PIP mothers were significantly less depressed at compared to the SC mothers. Children in PIP are significantly less likely to be stunted (24.3% vs 18.1%, p=0.013), to have better vocabularies and are less likely to be hospitalized than children in the SC condition. These data suggest home visits may need to continue for several years post-birth. Sustainable, scalable perinatal intervention models are needed in LMIC.
Major medical illnesses are associated with increased risk for depression and alterations in hypothalamic–pituitary–adrenal (HPA) axis function. Pathophysiological processes such as inflammation that occur as a part of medical illnesses and their treatments have been shown to cause depressive symptoms, and may also affect the HPA axis. We previously reported that patients with hepatitis C virus chronically administered interferon (IFN)-alpha develop increased evening plasma cortisol concentrations and a flattened diurnal cortisol slope, which correlated with increased tumor necrosis factor (TNF) and its soluble receptor 2 (sTNFR2). Increased TNF and sTNFR2 were further correlated with depression and fatigue scores. The current study examined whether flattened cortisol slope might be secondary to reduced glucocorticoid receptor (GR) sensitivity, by measuring glucocorticoid negative feedback to dexamethasone (DEX) administration followed by corticotropin releasing hormone (CRH) challenge. In an exploratory analysis, 28 male and female patients with hepatitis C virus were studied at baseline (Visit 1) and after 12 weeks (Visit 2) of either IFN-alpha plus ribavirin (n = 17) or no treatment (n = 11). Patients underwent dexamethasone DEX–CRH challenge, neuropsychiatric assessments, and measurement of plasma TNF and sTNFR2 during each visit. IFN-alpha did not affect neuroendocrine responses following CRH but did increase post-DEX cortisol, which was correlated with flattening of the diurnal cortisol slope (r = 0.57, p = 0.002) and with increased depression scores (r = 0.38, p = 0.047). Furthermore, the change in post-DEX cortisol was associated with IFN-alpha-induced increase in sTNFR2 (r = 0.51, p = 006), which was in turn correlated with depression (r = 0.63, p < 0.001) and fatigue (r = 0.51, p = 0.005) scores. Whereas the relationship between sTNFR2 and depression scores were independent of the change in post-DEX cortisol, the correlation between post-DEX cortisol and depression scores was not significant when controlling for sTNFR2. These findings suggest that inflammation induced in patients with hepatitis C virus during IFN-alpha therapy precipitates decreased GR sensitivity to lead to a flattened diurnal cortisol slope. Decreased GR sensitivity may in turn further increase inflammation and its ultimate effects on behavior. Treatments that target inflammation and/or GR sensitivity may reduce depressive symptoms associated with medical illnesses.
Researchers use protocols to screen for suspicious survey submissions in online studies. We evaluated how well a de-duplication and cross-validation process detected invalid entries. Data were from the Sexually Explicit Media Study, an Internet-based HIV prevention survey of men who have sex with men. Using our protocol, 146 (11.6 %) of 1254 entries were identified as invalid. Most indicated changes to the screening questionnaire to gain entry (n = 109, 74.7 %), matched other submissions’ payment profiles (n = 56, 41.8 %), or featured an IP address that was recorded previously (n = 43, 29.5 %). We found few demographic or behavioral differences between valid and invalid samples, however. Invalid submissions had lower odds of reporting HIV testing in the past year (OR 0.63), and higher odds of requesting no payment compared to check payments (OR 2.75). Thus, rates of HIV testing would have been underestimated if invalid submissions had not been removed, and payment may not be the only incentive for invalid participation.
The worldwide epidemic of metabolic syndromes and the recognized burden of mental health disorders have driven increased research into the relationship between the two. A maladaptive stress response is implicated in both mental health disorders and metabolic disorders, implicating the hypothalamic-pituitary-adrenal (HPA) axis as a key mediator of this relationship. This review explores how an altered energetic state, such as hyper- or hypoglycemia, as may be manifested in obesity or diabetes, affects the stress response and the HPA axis in particular. We propose that changes in energetic state or energetic demands can result in “energetic stress” that can, if prolonged, lead to a dysfunctional stress response. In this review, we summarize the role of the hypothalamus in modulating energy homeostasis and then briefly discuss the relationship between metabolism and stress-induced activation of the HPA axis. Next, we examine seven mechanisms whereby energetic stress interacts with neuroendocrine stress response systems, including by glucocorticoid signaling both within and beyond the HPA axis; by nutrient-induced changes in glucocorticoid signaling; by impacting the sympathetic nervous system; through changes in other neuroendocrine factors; by inducing inflammatory changes; and by altering the gut-brain axis. Recognizing these effects of energetic stress can drive novel therapies and prevention strategies for mental health disorders, including dietary intervention, probiotics, and even fecal transplant.
The ability to select between actions that are more vs. less likely to be reinforced is necessary for survival and navigation of a changing environment. A task termed "response-outcome contingency degradation" can be used in the laboratory to determine whether rodents behave according to such goal-directed response strategies. In one iteration of this task, rodents are trained to perform two food-reinforced behaviors, then the predictive relationship between one instrumental response and the associated outcome is modified by providing the reinforcer associated with that response non-contingently. During a subsequent probe test, animals can select between the two trained responses. Preferential engagement of the behavior most likely to be reinforced is considered goal-directed, while non-selective responding is considered a failure in response-outcome conditioning, or "habitual." This test has largely been used with rats, and less so with mice. Here we compiled data collected from several cohorts of mice tested in our lab between 2012 and 2015. Mice were bred on either a C57BL/6 or predominantly BALB/c strain background. We report that both strains of mice can use information acquired as a result of instrumental contingency degradation training to select amongst multiple response options the response most likely to be reinforced. Mice differ, however, during the training sessions when the familiar response-outcome contingency is being violated. BALB/c mice readily generate perseverative or habit-like response strategies when the only available response is unlikely to be reinforced, while C57BL/6 mice more readily inhibit responding. These findings provide evidence of strain differences in response strategies when an anticipated reinforcer is unlikely to be delivered.