nevertheless (Goldin-Meadow and Mylander, 1983). Evolution, it appears, has sculpted the human genome to be sensitive to and succoring of contact and relationships with others.
The need to belong does not stop at infancy; rather affiliation and nurturant social relationships are essential for physical and psychological well-being across the life span (Gardner et al., 2000; Seeman, 1996; Cohen and Syme, 1985). Affirmative social interactions—those satisfying needs for autonomy, competence, and relatedness—are related to feeling understood and appreciated (Reis, in press), and emotional disclosure improves affect and physical functioning among rheumatoid arthritis patients (Kelley et al., 1997). Disruptions of personal ties, whether through ridicule, discrimination, separation, divorce, or bereavement, are among the most stressful events people must endure (Gardner et al., 2000). Models of mental illness suggest that biological events (e.g., genetic heritage, in utero insult) produce a susceptibility to severe mental illness, but it is this vulnerability combined with the stress of life events, especially social events, that produces mood disorders, psychotic symptoms, or social apathy in late adolescence or early adulthood. Cognitive and interpersonal deficits in childhood and adolescence can further impair individuals from learning social and instrumental skills that help them avoid life stressors and achieve age-appropriate social roles. In sum, inadequate and restricted social connection during infancy and childhood has dramatic effects on psychopathology across the life span.
Relationships in adult life have been studied for their contributions to intimacy (Berscheid and Reis, 1998) and well-being (Myers and Diener, 1995; Ryff and Singer, 2000; Sternberg and Hojaat, 1997) as well as the adverse consequences of divorce and bereavement (Kiecolt-Glaser et al., 1998), deficits in belongingness (Baumeister and Leary, 1995), and dispositional and cognitive factors contributing to loneliness and depression (Cacioppo et al., in press b; Marangoni and Ickes, 1989). Studies show that marital dysfunction and conflict have significant physiological consequences. A study of older adults and long-term marriages showed that 30 minutes of conflict discussion was associated with increases in cortisol, adrenocorticotropic hormone, and norepinephrine in women but not in men (Kiecolt-Glaser et al., 1997). Other studies have linked marital conflict with high blood pressure (Ewart et al., 1991), elevated plasma catecholamine levels (Malarkey et al., 1994), and autonomic activation (Levenson et al., 1993).
Family life can also contribute to stress and dysfunctional coping with consequences for detrimental health behaviors (e.g., smoking, sedentary lifestyles, poor eating habits, type A behavior patterns). Characteristics of the family environment that may undermine the health of children and adolescents include a social climate that is conflictual and angry or even