Stress Is a Fact of Life for Young Children as Well as Adults

If asked to think of an example of someone affected by stress, most of us would probably imagine a college student studying all night for an exam or an employee scrambling to meet a deadline.

Few of us are likely to think of a child listening to his parents argue in the next room, and even fewer would picture an infant being ignored by a mother suffering from depression.

Although we may not be accustomed to the idea, children are just as vulnerable to stress as adults are. Neglect, abuse, family poverty, and exposure to domestic violence are just a few of the potential sources of stress during infancy and early childhood. They can also hinder optimal early brain development, between the ages 0-3. This is especially true of Memphis, where poverty- related stress is a challange many families face. Chronic early stress has been linked to behavioral and emotional problems in childhood as well as mental and physical illness later in life.1 A growing number of studies show that stress can result in changes in the structure and function of a child’s brain.2,3

Toxic stress can alter and impair a child’s brain.4

The word “stress” is often used informally to refer to feelings of anxiety or tension. But to understand the effects of stress, we need to understand its physical aspect. Stress is the body’s alarm system. When a challenge or threat occurs, the brain sets off a series of changes throughout the body. These changes shift resources away from nonessential functions and toward short-term energy and stamina.5

This process helps us deal with difficult or dangerous situations. But when our stress alarm goes off too often or for too long, it can produce wear and tear on the body and disrupt the stress system’s ability to switch on and off at appropriate times. This can have serious health consequences. Stress hormones like cortisol are powerful tools with multiple functions throughout the body, and when they are not well regulated, they can do widespread damage. Inappropriate levels of cortisol have been linked to high blood pressure, diabetes, rheumatoid arthritis, chronic fatigue syndrome, and depression.6

Stress endangers young children’s brain development. Persistent stress—sometimes called toxic stress—can interfere with the formation of the connections and networks that support thinking and learning.7 In extreme cases, it can result in permanent changes in the brain’s size and structure.2

Children are affected by stress even before they are born.

Babies are affected by stress even in the protective environment of the womb. A mother's level of stress during pregnancy influences her baby’s risk of premature birth, low birth weight, and other complications.8 Excess levels of cortisol can disrupt early brain development by interfering with the creation of neurons and with the development of synapses in some brain regions.9 Short-term effects can include fussiness, negative behavior, and fearfulness in infancy. Long-term outcomes can include cognitive delays, attention disorders, academic difficulties, and behavioral and emotional problems.10,11

After birth, of course, the number of potential stressors increases. Most of our knowledge about early childhood stress comes from studies of children with histories of neglect, abuse, or severe deprivation. These extreme forms of stress have been linked to abnormal brain structure and function.4 In recent years, more common sources of child stress have been gaining attention from researchers. These include harsh parenting, exposure to domestic violence, and maternal depression.

Early stress can have life-long effects.

A well-functioning stress response system is necessary for a child to cope with stress and adversity throughout life.12 Because it impairs the development of stress-related areas of the brain, toxic stress has the power to program a child's response system to be over-sensitive. One group of researchers found that infants whose parents frequently used corporal punishment showed stronger cortisol reactions than other infants to a mild stressor. Similarly, infants with emotionally withdrawn mothers had higher baseline cortisol levels than other infants.13

References: 

Shonkoff JP, Boyce WT, McEwen BS. Neuroscience, molecular biology, and the childhood roots of health disparities. Journal of the American Medical Association. 2009; 301:2252-2259.

Carrion VG, Weems CF, Reiss, AL. Stress predicts brain changes in children: A pilot longitudinal study on youth stress, PTSD, and the hippocampus. Pediatrics. 2007; 119: 509-516.

Hane AA, Fox NA. Ordinary variations in maternal caregiving influence human infants' stress reactivity. Psychological Science. 2006; 17(6): 550-556.

Teicher MH, Andersen SL, Polcari A, et al. The neurobiological consequences of early stress and childhood maltreatment. Neuroscience and Biobehavioral Reviews. 2003; 27(1-2): 33-44.

Flinn MV. Evolution and ontogeny of stress response to social challenge in the human child. Developmental Review. 2006; 26: 138-174.

Miller GE, Chen E, Zhou ES. If it goes up, must it come down? Chronic stress and the hypothalamic-pituitary-adrenocortical axis in humans. Psychological Bulletin. 2007; 133(1): 25–45.

Lewis MD. Self-organizing individual differences in brain development. Developmental Review. 2005; 25: 252–277.

Buss C, Floro JN, Andersen J, et al. Impact of maternal psychosocial stress on birth outcomes: a meta-analysis. Early Human Development. 2007; 83(Supplement 1): S173-S174.

Van den Bergh BR, Mulder EJ, Mennes M, Glover V. Antenatal maternal anxiety and stress and the neurobehavioural development of the fetus and child: links and possible mechanisms: a review. Neuroscience and Biobehavioral Reviews. 2005; 29: 237-58.

Bergman K, Sarkar P, Glover V, O'Connor TG. Maternal prenatal cortisol and infant cognitive development: moderation by infant-mother attachment. Biological Psychiatry. 2010; 67(11):1026-32

Buss C, Davis EP, Muftuler LT, et al. High pregnancy anxiety during mid-gestation is associated with decreased gray matter density in 6-9-year-old children. Psychoneuroendocrinology. 2010; 35: 141-153.

Weinstock M. The long-term behavioral consequences of prenatal stress. Neuroscience and Biobehavioral Reviews. 2008; 32: 1073-1086.

Data provided by University of Tennessee Health Science Center, Department of Preventive Medicine.

Dunkel-Schetter C. Maternal stress and preterm delivery. Prenatal and Neonatal Medicine. 1998; 3: 39-42.

DiPietro JA. The role of maternal prenatal stress in child development. Current Directions in Psychological Science. 2004; 13(2): 71-74.

Bugental DB, Martorell GA, Barraza V. The hormonal costs of subtle forms of infant maltreatment. Hormones and Behavior. 2003; 43: 237–244.

Gunnar M. Social regulation of stress in early child development. In McCartney K, Phillips D, Eds. Blackwell Handbook of Early Childhood Development. Malden, MA: Blackwell. 2006; 106–125.

Lorber MF, Egeland B. Infancy parenting and externalizing psychopathology from childhood through adulthood: developmental trends. Developmental Psychology. 2009; 45(4): 909-912.