Stress and the Developing Brain

by Beverly Gould

Understanding of the Developing Brain
Far-Reaching Harmful Effects of Stress
Events Early In Life Remain An Influence
Social Interaction Plays Major Role
Head Start Can Assist Healthy Brain Development
References

Some people believe that babies and young children are not affected by events that take place when they are very young, but what we do in the first three years has a tremendous impact on children's future development. 

Recent research and technological advances have changed our understanding of the developing brain. With this new information, parents and educators have the opportunity to provide children with interactions and settings that will allow them to reach their greatest potential. We now have a greater appreciation for the fact that the early years are a very fertile period in the child's life. We need to make conscious choices about how we treat children so that impact can be positive.

Research has demonstrated that there is an interaction between one's genetic endowment (nature) and the environment (nurture). Structural, hormonal, and chemical influences that are present during pregnancy affect the growth and development of the fetus. As early as three weeks after conception, a baby's brain cells begin to form (Berg 1994). These nerve cells then migrate to sections of the brain that will eventually control the reflexes, voluntary body movement, perception, language and thought. These structural changes–the cellular linkages being made–are unique to each individual infant. The linkages form as a result of the infant's experiences, both in the womb and once they are born.

Medical science continues to demonstrate the far-reaching harmful effects of stress. Stress is defined as an emotional reaction that elevates cognitive and physiological activity levels. It places demands upon the system for physical or cognitive productivity. When those demands are activated over a period of time, it progresses to a series of changes leading to exhaustion.

The degree of stress experienced by a woman while she is pregnant can have a negative affect on the fetus (Gunnar & Barr 1998). When maternal hormones, such as corticosterone and tryptophan, become overstimulated due to her own stressful conditions, there is a harmful chemical effect on the fetus' brain development.

The adult "fight or flight" response to stress is not an option for an infant or young child. Exposure to intense anger, loud screaming, or physical violence creates fear within the child that floods the brain with stress hormones. Being left alone and crying when hungry or wet are also conditions that create fear and stress in a young child. Various types of unpredictable, traumatic, chaotic, or neglectful environments physically change the brain by over-activating the neural pathways. As a result, there may be an increase in the child's muscle tone, profound sleep difficulties, an increased startle response, and significant anxiety. These responses, in turn, can lead to a permanent state of high alert, a tendency to misperceive the intentions and behavior of others, and the tendency to react with aggression.

Conscious memories of the first years of life are lost but the emotional part of the brain, referred to as the limbic system, and the body remember (Karr-Morse & Wiley 1997). An infant's first sense of what the world is like is recorded in the body. Without intervention, young children who have experienced high levels of stress will be at serious risk for emotional, behavioral, and learning difficulties.

Early Learning

Neuroscientist Dr. James LeDoux (1993) agrees that events early in life, experienced with strong emotions, can and do remain an influence throughout our lives. He suggests that what we feel is processed before what we think. Feelings experienced precognitively and preverbally continue to play out in later life even though the individual may have no conscious memory of the association. A significant trauma that takes place often or intensely enough can rob a child of the ability to learn normally by pulling away brain circuitry meant for other tasks.

An area of the brain, referred to as the amygdala, is central in understanding how stress affects learning. The amygdala governs attention, memory, planning, and behavior–all skills necessary for the child to be able to take in and process information. Difficulties in attention often include distractibility and impulsivity, which impair problem solving. In social situations, children who are overly active, impulsive, and unable to focus tend to have trouble reading others' social cues and responding appropriately to others in the environment.

Role of Relationships

Research links the external environmental influences on brain development with the quality of stimulation and degree to which the caregiver is attuned to the needs of the infant. Social interaction with an empathetic and attuned caregiver plays the major role in the growth and regulation of the child's nervous system and in helping the child develop the strength needed to become socially competent and able to learn. The consistent experience of empathy that takes place with an emotionally available caregiver gradually builds the child's capacity to empathize with others.

Relationships that a child experiences provide the foundations for approaches to learning, which, hopefully, will be enthusiastic, curious, and persistent. Stanley Greenspan (1997), a noted child psychiatrist, explains that the capacity to feel a full range of emotions–learned through relationships–allows children to organize events and ideas before they have the words to express them. Children learn how to think by creating ideas based on their experiences and how it feels to engage in those experiences. For example, young children become more focused and interactive through being able to enjoy the excitement of reciprocal play. The playful and creative give and take with an emotionally present, verbal adult motivates the development of language and encourages the child toward discriminating, generalizing, categorizing, and organizing her experiences. This is the basis for the ability to think first concretely and then abstractly.

The Abecedarian Project at the University of Alabama (Campbell & Ramey 1994) found that when at-risk young children were exposed to a stimulating environment, appropriate toys, playmates, and good nutrition, they developed less mental retardation than the control group. Early intervention in infancy, when the neurological circuits for learning are being formed, resulted in higher IQs in comparison to the control group. The conclusion was that early enrollment in a high quality, enriched day care setting is paramount to the children's significant and long-lasting improvements.

How Head Start Can Help

Head Start is in a unique position to assist in healthy brain development.

In addition to the developmental assessments required by the Head Start Program Performance Standards, an assessment of the interaction between the caregiver and the child can identify relationship issues that might need mental health intervention. The ability of caring and well-informed Head Start staff to recognize problems early can prevent difficulties that would be much more difficult to remedy later.

Classroom teachers and home visitors play a crucial role in optimizing healthy brain development. Infant researcher Ron Lally (1995) points out the key role the infant/toddler caregiver plays in the development of the child's sense of identity. Through imitation and absorption of the environment, children form their sense of who they are in the world. Helen Raikes (1993) cited the importance that a relationship between a child and a high quality teacher plays in "modulating attention, creating interest, building trust, and assuring predictability for the infants." This is especially true when the child is given the time needed with one teacher, as opposed to multiple interactions from a variety of caregivers. The time spent building this attachment allows the teacher to fine-tune her interactions based on her intimate knowledge of the individual child and his needs and responses. Both parents and children can be supported in Head Start to minimize stressful situations that impede healthy development. 

References

Berg, B. 1994. Child neurology: A clinical manual. Philadelphia: J.B. Lippincott Company.

Campbell, F.A. & C.T. Ramey. 1994. Effects of early intervention on intellectual and academic achievement: A follow-up study of children from low-income families. Child Development 65: 684-698.

Gunnar, M.R. & R.G. Barr. 1998. Stress, early brain development, and behavior. Infants and Young Children 11(1): 1-14.

Greenspan, S. & B. Benderly. 1997. The growth of the mind: And the endangered origins of intelligence. Boulder, CO: Perseus Books Group.

Karr-Morse, R. & M. Wiley. 1997. Ghosts from the nursery. New York: The Atlantic Monthly Press.

Lally, J.R. 1995. The impact of child care policies and practices on infant/toddler identity formation. Young Children 51(1): 58-67.

LeDoux, J. 1993. Emotional memory systems in the brain. Behavioral Brain Research 58.

Raikes, H. 1993. Relationship duration in infant care: time with high ability teacher and infant-teacher attachment. Early Childhood Research Quarterly 8: 309-325.

Beverly Gould was a 2000-2001 Head Start Fellow