This meta-analysis reviews 208 laboratory studies of acute psychological stressors and tests a theoretical model delineating conditions capable of eliciting cortisol responses. Psychological stressors increased cortisol levels; however, effects varied widely across tasks. Consistent with the theoretical model, motivated performance tasks elicited cortisol responses if they were uncontrollable or characterized by social-evaluative threat (task performance could be negatively judged by others), when methodological factors and other stressor characteristics were controlled for. Tasks containing both uncontrollable and social-evaluative elements were associated with the largest cortisol and adrenocorticotropin hormone changes and the longest times to recovery. These findings are consistent with the animal literature on the physiological effects of uncontrollable social threat and contradict the belief that cortisol is responsive to all types of stressors.

Psychological beliefs such as optimism, personal control, and a sense of meaning are known to be protective of mental health. Are they protective of physical health as well? The authors present a program of research that has tested the implications of cognitive adaptation theory and research on positive illusions for the relation of positive beliefs to disease progression among men infected with HIV. The investigations have revealed that even unrealistically optimistic beliefs about the future may be health protective. The ability to find meaning in the experience is also associated with a less rapid course of illness. Taken together, the research suggests that psychological beliefs such as meaning, control, and optimism act as resources, which may not only preserve mental health in the context of traumatic or life-threatening events but be protective of physical health as well.

Our program of research focuses on shame as a key emotional response to "social self" threats (i.e., social evaluation or rejection). We propose that shame may orchestrate specific patterns of psychobiological changes under these conditions. A series of studies demonstrates that acute threats to the social self increase proinflammatory cytokine activity and cortisol and that these changes occur in concert with shame. Chronic social self threats and persistent experience of shame-related cognitive and affective states predict disease-relevant immunological and health outcomes in HIV. Across our laboratory and longitudinal studies, general or composite affective states (e.g., distress) are unrelated to these physiological and health outcomes. These findings support a stressor- and emotional response-specificity model for psychobiological and health research.

Threat to the social self is an important elicitor of shame experience, decreases in social self-esteem and cortisol increases under demanding performance conditions. Cortisol changes may be specifically tied to the experience of emotions and cognitions reflecting low self-worth in this context.