Childhood Stress and Family Environment

Childhood Stress and Family Environment Kyle Krueger, Jon Schectman, Jennifer Clay

Biology of Stress Function of the limbic system and basal ganglia (SAM) – Sympathetic-adrenal-medullary Epinephrine and norepinephrine (HPA) – Hypothalamus-pituitary-adrenal Glucocorticoids Cortisol

Effects of Stress Cortisol modulates Energy Immune activity Mental alertness Learning Memory encoding Why do we care about cortisol and family environment? Psychosocial stress and uncertainty

Costs of Stress Chronic stress can lead to: Immunity deficiencies Stunted growth Hippocampal damage Cognitive impairment Permanent alteration of HPA functioning Prenatal drug exposure Abuse victims

Challenges Factors influencing cortisol levels: Circadian rhythm Food consumption Physical activity Emotional distress? Time course of endocrine functions Individual variation Temperament

A Useful Approach How do we account for all of these factors? Longitudinal Anthropological study Both behavior and cortisol assay Short-term as well as long-term events Provides cultural context Cultural significance of events Individuation of subjects Personality Past experiences

Population 247 Children 2 months-18 years from 82 homes-nearly complete sample BwaMawego, rural village in Dominica +/- 780 residents Divided into 5 neighborhoods, 4 of which were involved in this study Mixed African, Carib, and European descents

About BwaMawego • Small houses, most have kitchen and toilet as outbuildings • Children typically sleep together • Wealthier houses have sitting rooms • ~60% of homes and electricity • Part time residence common • Large farming and fishing community • No running water-obtained from springs, catchments and run-off from roofs

Methods and Field Techniques • Interviews, behavioral scans, participant observation, and questionnaire instruments • Household environment, caretaking attention, temperament, and health • Radioimmunoassay of saliva samples • Physiological stress response Primary focus of this report in on relations between stress (dependent variable) and family environment (independent variable)

Saliva collection • Routine 1: • Twice daily collection • 16,652 of 18,376 collections this way • Routine 2: • “focal follow” • Child/infant was observed from dawn until early afternoon with hourly saliva samples

Data was NOT adjusted for… • Eating and caffeine intake • Few samples were taken during mealtime • Small effect • Intensive physical exertion • Only small amount of samples taken during physical exertion • Difficult to determine degree of exertions

Circadian Rhythm • 24-hour cycle in biochemical, physiological, or behavioral processes • Includes release of cortisol!

Results

From these results, the conclusion is that childhood stress is associated with household composition • Children in difficult caretaking environments may experience… • chronic stress • more acute stressors • More frequent stressful events • May have inadequate coping abilities, perhaps developed from difficult experiences in early childhood

Chronic Stress • Chronic stress… • May deplete cellular energy and immune reserves that require subsequent conservation to rebuild normal cortisol • Along with high average cortisol levels are associated with frequency of illness

“Sensitive Periods” • Longitudinal analysis of caretaking histories suggest that children have “sensitive periods” for development of stress response • Children with severe caretaking problems during INFANCY frequently exhibit one of two cortisol profiles • Unusually low with occasional high spikes • Chronically high cortisol levels • Step children are more likely to have unusual cortisol profiles and inhibited temperaments

Low-basal-with-high spikes cortisol profile children all have low sociability and high aggressiveness. All children with the chronically high cortisol profile have shyness and social anxiety.

High Stress • High stress does not mean the events that triggered were traumatic or “negative” • Eating meals • Hard physical work • Routine competitive play • Return of a family member who was temporarily absent

Summary • Stress coping mechanisms • Beneficial in the short term • Consume extensive resources • Leave the body vulnerable after prolonged use • Children are especially sensitive to stress • Might be due to extreme exposure • Its hard to escape parents • Children have sensitive periods, this allows them to learn better during certain times.

Discussion • Limitations • Only used sample of people in a rural village • Did stress levels of parents interact with that of children. • If parents did not act stress did their cortisol levels effect those of their children • Not experimental or controlled

Future studies • Take place in the city • Does children’s stress effect parents • Explicit effects on personality • Does animal parental stress effect children or is this uniquely human • Mediation of effects?

Implications Parents need to be extra attentive to stress levels. A bad start can lead to repeated stress Small amounts of stress may lead to development of coping mechanisms Engaging children in activities that activate stress could be beneficial. I.E. Sports. Children need strong support systems

Relationship to EP • Stress in the environment is relatively short lived • Zebra gets attack, zebra runs, stress is over. • In modern times stressful situations last much longer • Imagine being attacked by a lion 8 hours a day. • Supported by finding that stress levels in people decrease after short time. • Could be adaptive to respond to parents feelings quickly. E.X. Mom scared of lion, good to scare

Some Thoughts • Do these findings support the Life-History theory of personality development? • Are these reflective of Daly & Wilson’s findings on-step-children outcomes • Can all of these stress responses be considered adaptive?

Childhood Stress and Family Environment