Washington: Facing adversities and challenges during the early years of lives affect children’s executive function skills and their ability to focus and organize tasks, recent findings suggest.
According to the study, experiences such as poverty, residential instability, or parental divorce or substance abuse, can lead to changes in a child’s brain chemistry, muting the effects of stress hormones. These hormones are responsible to help us face challenges, stress, or to simply help us “get up and go.”
Together, these impacts to executive function and stress hormones create a snowball effect, adding to social and emotional challenges that can continue through childhood.
As part of this study, a team of researchers examined how adversity can change the ways children develop.
“This study shows how adversity is affecting multiple systems inside a child. The disruption of multiple systems of self-control, both intentional planning efforts and automatic stress-hormone responses, set off a cascade of neurobiological effects that start early and continues through childhood,” said Liliana Lengua, lead author of the study and director of the Center for Child and Family Well-Being.
The study, published in the Journal of Development and Psychopathology, evaluated 306 children at intervals over more than two years, starting when participants were around 3 years old, up to age 5 1/2 . Children were from a range of racial, ethnic and socioeconomic backgrounds, with 57 per cent considered lower income or near poverty.
Income was a key marker for adversity. In addition, the children’s mothers were surveyed about other risk factors that have been linked to poor health and behaviour outcomes in children, including family transitions, residential instability, and negative life events such as abuse or the incarceration of a parent.
Against these data, Lengua’s team tested children’s executive function skills with a series of activities, and, through saliva samples, a stress-response hormone called diurnal cortisol.
Cortisol, the hormone that “helps us rise to a challenge’, tends to follow a daily, or diurnal, pattern: It increases early in the morning, helping us to wake up. It is highest in the morning — think of it as the energy to face the day — and then starts to fall throughout the day.
But the pattern is different among children and adults who face constant stress, Lengua said.
“When someone is faced with high levels of stress all the time, the cortisol response becomes immune, and the system stops responding. That means they’re not having the cortisol levels they need to be alert and awake and emotionally ready to meet the challenges of the day,” she said.
To assess executive function, researchers chose preschool-friendly activities that measured each child’s ability to follow directions, pay attention and take actions contrary to impulse. For instance, in a game called “Head-Toes-Knees-Shoulders,” children are told to do the opposite of what a researcher tells them to do — if the researcher says, “touch your head,” the child is supposed to touch their toes. In another activity, children interact with two puppets — a monkey and a dragon — but are supposed to follow only the instructions given by the monkey.
When children are better at following instructions in these and similar activities, they tend to have better social skills and manage their emotions when stressed. Children who did well on these tasks also tended to have more typical patterns of diurnal cortisol.
But children who were in families that had lower income and higher adversity tended to have both lower executive function and an atypical diurnal cortisol pattern. Each of those contributed to more behaviour problems and lower social-emotional competence in children when they were about to start kindergarten.