Early Infancy

According to Lewis, Thomas, and Worodobey, 1990, individuals, from early infancy, vary in in their physiologic, behavioral, and physiologic responses to standard stressor. They studied theses individuals differences and reported that it could lead to a model of stress susceptibility, which in fact, might explain, more clearly, the patterns of childhood morbidity. In this study researchers decided that they wanted to explore the relationships that occurred among physiologic and behavioral responses to a standardized stressor, parent-reported temperament, and numbers of infections and atopic disorders in the first years of life. The standardized stressor was a routine immunization. They studied infants between the ages of 2- (n=30) and 4-month (n=24) routine clinic visits. Behavioral data was coded from videotapes filmed for 90 seconds after immunizations. Salivary cortisol measured psychological arousal; specimens were o...