Family Income and Appraisals of Parental Conflict as Predictors of Psychological Adjustment and Diurnal Cortisol in Emerging Adulthood Rachel G. Lucas-Thompson Colorado State University Camelia E. Hostinar University of Minnesota The goal of the current study was to provide the first investigation of whether appraisals of parental marital conflict mediate associations of family income with emerging adult psychological adjustment and diurnal cortisol production. Participants were 178 college students who provided 3 saliva samples across the day and reported their family income, adjustment (depressive symptoms, perceived daily stress, internalizing problems, and externalizing problems), and appraisals of their parents’ conflict (including perceptions of frequency, intensity, resolution, stability, as well as perceived threat and self-blame for conflict). Results indicated that emerging adults from low-income families reported more-negative conflict appraisals, which in turn predicted lower levels of adjustment; there was no association between income and patterns of cortisol production across the day. However, emerging adults who felt responsible for their parents’ conflict displayed cortisol levels that were lower early in the day, with a tendency toward blunted cortisol slopes across the day; those who appraised their parents’ conflict less negatively displayed a more normative pattern of cortisol production. These results suggest that effects of family income on psychological adjustment are explained, in part, by appraisals of parental conflict, particularly of appraisals of conflict as threatening, whereas self-blame conflict appraisals have main effects on cortisol, and predict a dysregulated and potentially maladaptive pattern of cortisol production across the day for emerging adults. Keywords: family income, mental health, adjustment, diurnal cortisol, emerging adulthood, parental conflict, structural equation modeling Growing up in a family experiencing low income or poverty has ramifications for physical and mental health, achievement, and socioemotional functioning (Evans, 2004) that persist from infancy into adulthood (Bradley & Corwyn, 2002). Family process models (e.g., Conger et al., 1991; Elder, 1974) highlight the importance of family relationships, which are disrupted by economic stress, as potent mediators of these effects. Past research has focused on disruptions in parenting as a mediator, despite arguments that marital conflict is an important mediator (e.g., Conger et al., 1991; Elder, 1974), and that children’s appraisals of their parents’ marital conflict are an important mechanism by which conflict operates (Grych & Fincham, 1990). In addition, a family process model has not been applied to understand whether family relationships me- diate the consistently noted associations between income and stress physiology (e.g., circulating levels of the stress hormone cortisol) (Cohen, Doyle, & Baum, 2006; Evans & English, 2002; Li, Power, Kelly, Kirschbaum, & Hertzman, 2007; Lupien, King, Meaney, & McEwen, 2000). Rooted in family process models, the goals of the current study were to examine whether appraisals of parental marital conflict mediate associations between family in- come, adjustment, and stress physiology. These associations were examined in a neglected age period, “emerging adulthood” (Ar- nett, 2000), a period when family relationships are changing but are still important for offspring functioning (e.g., Larose & Boivin, 1998). Family Income as a Predictor of Negative Developmental Outcomes Across the life span and in many different racial/ethnic groups, individuals experiencing poverty or economic stress report more mental health and adjustment problems, including internalizing (e.g., Evans & English, 2002; Hammack, Robinson, Crawford, & Li, 2004) and externalizing problems (e.g., Conger et al., 1991). Low income individuals also report experiencing many more and often multiple stressors compared to other individuals (Evans & English, 2002; Hammack et al., 2004). Because individuals from low-income families report more stressors, researchers have ex- amined whether income predicts stress physiology. Varied and multiple stressors can activate the hypothalamic-pituitary- adrenocortical (HPA) axis, an important arm of the human stress response system (e.g., Hostinar & Gunnar, 2013). Cortisol is the end-product of the HPA axis, and basal cortisol levels have been linked to numerous psychological and physical health outcomes (Chrousos, 2009). A well-documented diurnal cortisol pattern has been observed, with healthy individuals showing a peak shortly after waking and then steady declines for the rest of the day (e.g., Stone et al., 2001). Rachel G. Lucas-Thompson, Human Development and Family Studies, Colorado State University; Camelia E. Hostinar, Institute of Child Devel- opment, University of Minnesota. Correspondence concerning this article should be addressed to Rachel G. Lucas-Thompson, Human Development and Family Studies, Colorado State University, Campus Delivery 1570, Fort Collins, CO 80523-1570. E-mail: Lucas-Thompson.Rachel.Graham@colostate.edu This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. Journal of Family Psychology © 2013 American Psychological Association 2013, Vol. 27, No. 5, 784 –794 0893-3200/13/$12.00 DOI: 10.1037/a0034373 784