The power of nurture: Early experiences impact brain development
February 25, 2016 0 Comments
Researchers have suggested that our vulnerability to developing problems such as substance abuse, mental illness and certain medical conditions derives from the interaction between our genes and the environment. Genetic factors underlie the development of certain mental disorders, including schizophrenia, alcoholism and depression, making it much more likely that children of parents with these psychiatric disorders will go on to develop mental health problems themselves — but this isn’t always the case.
Social and environmental risk factors (e.g., low income and poverty, stress, family conflict, injustice and discrimination, child maltreatment, abuse or neglect, exposure to war or disaster, etc.) can also affect children’s vulnerability for developing mental health problems. Prenatal development and maternal health during pregnancy are also major factors in children’s development, and pregnant women’s exposure to certain environmental toxins and risk factors (e.g., stress and influenza infections) further increases children’s vulnerability for developing mental disorders including schizophrenia.
Even without the genetic risk factors, it has become very clear that children’s early life experiences can increase their vulnerability for developing an addiction, depressive disorder, anxiety disorder or other mental illness, especially when they have certain social and environmental risk factors present.
Social and environmental risk factors
Certain environmental risk factors (e.g., poverty) can increase the likelihood that children will develop certain mental health conditions, behavioral problems and substance abuse. Exposure to early-life stress-provoking experiences can affect the development of the brain’s circuitry and communication, and make children more vulnerable to emotional and cognitive problems later in life.
Children born to socioeconomically disadvantaged parents are at a higher risk of neurological abnormalities and autonomic nervous system dysfunction by the time they are 7 years old, according to the study published in the International Journal of Epidemiology. Children’s early experiences of fragmented, chaotic or disrupted maternal care can also disrupt brain development, increasing their vulnerability to developing a number of social, emotional and behavioral problems.
Particularly early in life, the presence of social and environmental risk factors, including poverty, parental substance abuse and lack of adequate caregiving, can have a major influence on the way that children learn to view themselves and others, form their relationships and deal with stress. For example, children who receive disruptive, erratic and chaotic maternal care are more likely to engage in risky behaviors, drug seeking and depression in adolescence and adulthood and are more vulnerable for developing mental disorders later in life.
Importance of maternal care
Early maternal care is particularly important because it is a primary source of environmental sensory signals to the infant’s developing brain. Researchers have suggested that the brain’s dopamine-receptor circuits — responsible for pleasure — are not fully mature in newborns and infants, and require stimulation by predictable sequences of events.
One study indicated that maternal care can affect children’s development of dopamine-receptor pleasure circuitry responsible for our ability to experience pleasure. Tallie Z. Baram, M.D., Ph.D., and her colleagues investigated the underlying neural mechanisms of unpredictable and fragmented maternal care on the development of depressive symptoms in an animal model of rodents.
Maternal care that is unpredictable and fragmented may disrupt maternal-derived sensory input to the developing brain, according to a study conducted by Baram and her colleagues. The researchers suggested that children may be more likely to develop anhedonia (i.e., inability to experience pleasure) — one of the main symptoms of depression — when they do not receive consistent and predictable sensory signals early in life.
Furthermore, infants raised in chaotic home environments with unpredictable and fragmented maternal care are not adequately exposed to reliable patterns that assist the pleasure systems in developing properly, and this can contribute to genetic vulnerability to stress-related neuropsychiatric disorders.
Early life experiences and child outcomes
Children who form secure attachments with their parents have better social, emotional, cognitive and behavioral developmental outcomes. Security and trust in caregivers is more likely to develop when parents are responsive, consistent and reliable in providing for children’s basic needs (i.e., safety, security, love and survival). Children are also more likely to develop competency, empathy, resilience and self-confidence, and get along better with other children when they have early experiences with parents who are competent, attentive to their needs and consistently there, said Mokhtar Malekpour, Ph.D., a professor at Islamic Azad University.
Child care that is fragmented, stressful and inconsistent can have consequences on the development of the brain. Baram and her colleagues suggest that the lack of early parental nurturing as well as certain environmental factors can increase children’s susceptibility to developing mental health disorders such as depression and highlight the importance of early child care and environments on mental health.
White River Academy is a therapeutic boarding school for boys ages 12 to 17 affected by mental illness, substance abuse and co-occurring disorders. Our behavioral treatments are evidence-based and individualized to meet each adolescent’s specific needs. For more information about White River Academy’s therapeutic treatment facility, please contact our 24/7 helpline to speak to a member of our team.
About the author
Amanda Habermann is graduated from California Lutheran University, she received her M.S. in clinical psychology with an emphasis in psychiatric rehabilitation. She brings to the team her background in research, testing and assessment, diagnosis and recovery techniques.