Physiological Regulation and Fearfulness as Predictors of Young Children's Empathy-related Reactions.

Indices of physiological regulation (i.e., resting respiratory sinus arrhythmia [RSA] and RSA suppression) and observed fearfulness were tested as predictors of empathy-related reactions to an unfamiliar person's simulated distress within and across 18 (T1, N = 247) and 30 (T2, N = 216) months of age. Controlling for T1 helping, high RSA suppression and low fearfulness at T1 predicted T2 helping. In a structural model, empathic concern was marginally positively related to resting RSA at both assessments whereas personal distress was related to RSA suppression within time (marginally positively at T1 and significantly negatively at T2). Fearfulness was associated with self-oriented, distress-related reactions within time. Comfort seeking (an index of personal distress) declined in mean level with age whereas helping increased, and both behaviors exhibited differential continuity (as did resting RSA). Individual, as well as developmental, differences in the types of reactions that young children exhibit when witnessing others' suffering and distress were discussed.

Individual differences in preschoolers' salivary cortisol and alpha-amylase reactivity: relations to temperament and maladjustment.

We examined the relations of 84 preschoolers' (43 boys; mean age=54 months) situational stress reactivity to their observed emotions and mothers' reports of temperament and adjustment. Salivary cortisol and salivary alpha-amylase (sAA) were collected prior to, and following, a frustrating task. Children's anger, sadness, and positive affect were measured, and mothers reported on preschoolers' dispositional emotionality, regulation, impulsivity, and problem behaviors. Forty-seven percent of children had an increase in sAA and 52% had an increase in cortisol following the challenging task. On average, sAA levels showed the predicted pattern of rise following the frustrating task, followed by return to baseline. For cortisol, there was a mean increase from pre-task to 40 min post-test. sAA reactivity was associated with relatively low levels of dispositional anger and impulsivity and relatively high regulation, particularly for girls. sAA reactivity also was related to low externalizing problems for girls, but not boys. Although cortisol reactivity was unrelated to children's emotions and maladjustment, it was positively related to mothers' reports of regulation. The findings suggest that sAA reactivity in response to a frustrating social task may reflect girls' constrained behavior.