ROCHESTER, N.Y., July 8 (UPI) -- Children's personalities -- cautious and submissive or bold and assertive -- are linked to their chemical response to stress, U.S. researchers say.
Lead author Patrick Davies of the University of Rochester and colleagues say the study involved 201 2-year-old toddlers, all from impoverished families with similar socio-economic profiles.
The researchers documented the dovish or hawkish tendencies of the toddlers in a variety of unfamiliar situations. Children who showed dovish tendencies were vigilant and submissive, clung to their mothers, cried, or froze encountering new surroundings, while hawks used bold, aggressive and dominating coping strategies and fearlessly explored unknown objects and new environments.
The children were exposed to a mildly stressful simulated telephone argument between their parents.
Doves with parents who fought violently produced elevated levels of cortisol, a hormone that is thought to increase a person's sensitivity to stress, while hawks from similar home environments halt cortisol production, which is regarded as a marker for diminishing experiences of danger and alarm.
"This high-and-low-cortisol reactivity provides different developmental advantages and disadvantages," the study authors said. "Heightened cortisol levels characteristic of the doves were related to lower attention problems but also put them at risk for developing anxiety and depression, while lower cortisol levels for hawks were associated with lower anxiety problems, but prone to risky behavior, including attention and hyperactivity problems."
The study is published online in Development and Psychopathology.
