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

•247 Children 2 months-18 years from 82 homes-nearly complete sample•Bwa Mawego, rural village in Dominica

•+/- 780 residents•Divided into 5 neighborhoods, 4 of which were involved in this study

•Mixed African, Carib, and European descents

Population

About Bwa Mawego 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 collectionRoutine 1:

Twice daily collection16,652 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 Rhythm24-hour cycle in biochemical, physiological,

or behavioral processesIncludes release of cortisol!

Results

Results

From these results, the conclusion is that childhood stress is associated with household compositionChildren 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 StressChronic 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 responseChildren 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 StressHigh 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

SummaryStress coping mechanisms

Beneficial in the short termConsume extensive resources

Leave the body vulnerable after prolonged use

Children are especially sensitive to stressMight be due to extreme exposure

Its hard to escape parentsChildren have sensitive periods, this allows

them to learn better during certain times.

DiscussionLimitations

Only used sample of people in a rural villageDid stress levels of parents interact with that

of children. If parents did not act stress did their cortisol levels

effect those of their childrenNot experimental or controlled

Future studiesTake place in the cityDoes children’s stress effect parentsExplicit effects on personalityDoes animal parental stress effect children or

is this uniquely humanMediation 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 EPStress in the environment is relatively

short livedZebra 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 ThoughtsDo these findings support the Life-History

theory of personality development?Are these reflective of Daly & Wilson’s

findings on-step-children outcomesCan all of these stress responses be

considered adaptive?