Relationship between COVID-related stressors and internalizing symptoms: Gendered neuroendocrine risk profiles.

The COVID-19 pandemic generated significant life stress and increases in internalizing disorders. Moreover, COVID-related stressors disproportionately impacted women, consistent with outcomes showing a gender gap in stress-related disorders. Gender-related stress vulnerability emerges in adolescence alongside gender-specific changes in neuroendocrine signaling. Most research on the neuroendocrinology of stress-related disorders has focused on differences in the hypothalamic-pituitary-adrenal (HPA) axis effector hormone cortisol. More recent studies, however, emphasize dehydroepiandrosterone (DHEA), a neuroprotective and neuroactive hormone released concurrently with cortisol that balances its biobehavioral actions during stress. Notably, women show lower cortisol responses and higher DHEA responses to stress. However, lower cortisol and higher DHEA are associated with internalizing disorders in women, while those associations are opposite in men. Thus, gender-specific factors perhaps result in a neuroendocrine profile that places women at greater risk for stress-related disorders. The current study prospectively examined socially evaluated cold-pressor task (SECPT) induced neuroendocrine responses at age 15 and internalizing symptoms during the COVID-19 pandemic at age 21 in a cohort of 175 primarily Black low-socioeconomic status participants, while controlling for internalizing symptoms at age 15. The association between COVID-related stress and internalizing symptoms was not stronger in women. Lower DHEA-cortisol ratios were associated with a weaker relationship between COVID-related stress and internalizing symptoms in women, while higher ratios were associated with a weaker relationship in men. These findings suggest gender differences in the relationship between DHEA and cortisol and internalizing outcomes during a stressful period, and support differential neuroendocrine protective and risk pathways for young men and women.

Parent Mental Health Before and During the COVID-19 Pandemic.

Although extant cross-sectional data suggest that parents have experienced numerous challenges (e.g., homeschooling, caregiver burden) and mental health consequences during the COVID-19 pandemic, longitudinal data are needed to confirm mental health changes relative to pre-pandemic levels and identify which specific pandemic-related changes most highly predict mental health during the pandemic. In two longitudinal subsamples (N = 299 and N = 175), we assessed change in anxiety, depression, and stress before and during the pandemic and whether the accumulation of pandemic-related changes predicted observed mental health changes. On average, parents reported increased depression and anxiety, but no significant changes in reported stress. Moreover, increased interpersonal conflict, difficulty managing work and caregiving responsibilities, and increased economic challenges were the types of pandemic-related changes that most strongly predicted worse mental health, highlighting that juggling caregiving responsibilities and economic concerns, along with the pandemic's impact on interpersonal family relationships are key predictors of worsening parental mental illness symptoms.

Early childhood household instability, adolescent structural neural network architecture, and young adulthood depression: A 21-year longitudinal study.

Unstable and unpredictable environments are linked to risk for psychopathology, but the underlying neural mechanisms that explain how instability relate to subsequent mental health concerns remain unclear. In particular, few studies have focused on the association between instability and white matter structures despite white matter playing a crucial role for neural development. In a longitudinal sample recruited from a population-based study (N = 237), household instability (residential moves, changes in household composition, caregiver transitions in the first 5 years) was examined in association with adolescent structural network organization (network integration, segregation, and robustness of white matter connectomes; Mage = 15.87) and young adulthood anxiety and depression (six years later). Results indicate that greater instability related to greater global network efficiency, and this association remained after accounting for other types of adversity (e.g., harsh parenting, neglect, food insecurity). Moreover, instability predicted increased depressive symptoms via increased network efficiency even after controlling for previous levels of symptoms. Exploratory analyses showed that structural connectivity involving the left fronto-lateral and temporal regions were most strongly related to instability. Findings suggest that structural network efficiency relating to household instability may be a neural mechanism of risk for later depression and highlight the ways in which instability modulates neural development.

Examining the role of olfaction in dietary choice.

Obesity is frequently caused by calorie-rich dietary choices across the animal kingdom. As prandial preference toward a high-fat diet develops in mice, an anti-preference or devaluation of a nutritionally balanced but less palatable standard chow diet occurs concomitantly. Although mechanistic insights underlying devaluation have been observed physiologically in the brain, it is unclear how peripheral sensory processing affects food choice. Because olfactory cues and odor perception help coordinate food preference and intake, we determine the role of smell in the targeted consumption of a high-fat diet and simultaneous devaluation of a standard chow diet. Using inaccessible food and loss-of-function manipulations, we find that olfactory information is neither sufficient nor necessary for both the acute and chronic selection of high-fat diet and coincident diminished value of standard diet. This work suggests alternative means are behind the immediate and sustained consumption of high-fat diet and concurrent standard diet devaluation.

High-fat food biases hypothalamic and mesolimbic expression of consummatory drives.

Maintaining healthy body weight is increasingly difficult in our obesogenic environment. Dieting efforts are often overpowered by the internal drive to consume energy-dense foods. Although the selection of calorically rich substrates over healthier options is identifiable across species, the mechanisms behind this choice remain poorly understood. Using a passive devaluation paradigm, we found that exposure to high-fat diet (HFD) suppresses the intake of nutritionally balanced standard chow diet (SD) irrespective of age, sex, body mass accrual and functional leptin or melanocortin-4 receptor signaling. Longitudinal recordings revealed that this SD devaluation and subsequent shift toward HFD consumption is encoded at the level of hypothalamic agouti-related peptide neurons and mesolimbic dopamine signaling. Prior HFD consumption vastly diminished the capacity of SD to alleviate the negative valence associated with hunger and the rewarding properties of food discovery even after periods of HFD abstinence. These data reveal a neural basis behind the hardships of dieting.