There may be a link between a baby's energy levels and their sensitivity to environmental stimuli, meaning that some babies are more affected by nurture than others, researchers at the Ben-Gurion University of the Negev published in the Infant and Child Development Journal earlier this month.
The peer-reviewed study, led by Tzlil Eizinger, followed 95 Israeli boys from birth to age seven. At one month old, the babies were assessed for early temperamental traits such as energy levels, responses to stimuli, and soothability.
Certain infants were described as having “early surgency,” the ones who responded more energetically and positively, and overall showed greater engagement with their surroundings.
These children with “early surgency” were later found to display an unexpected pattern; they were more affected by nurture than the others.
The children with greater energy as infants had higher environmental sensitivity, directly influencing their cognitive development, and thus their potential to manifest symptoms of ADHD.
How does the study challenge previous perceptions?
The study challenges the idea that early biological traits linked to ADHD are always negative.
The children with “early surgency” were more vulnerable to harm but were also more capable of benefitting from a positive environment; the levels of enrichment around them had a greater impact on their outcomes than it did on the children without increased sensitivity.
Among children with “early surgency” and a family history of ADHD, being raised in an enriched home meant they performed as well as or better than their less sensitive peers, highlighting that some individuals may be more open to environmental factors, both to their benefit and detriment.
The researchers found that some traits of ADHD that are usually associated with difficulties may also be reflective of a heightened capability to thrive under appropriate conditions.
Previous studies often grouped children into simple, distinct categories: resilient or at risk. This study challenged those categories, adding to the growing evidence that development is more nuanced than resilient or at risk.
"There aren’t just ‘sensitive’ and ‘non-sensitive’ children," explains Prof. Andrea Berger, co-author of the study, "sensitivity exists on a continuum, shaped by the interaction between child temperament and parental characteristics."
The study looks at the differences between how children, even those with similar risk factors, respond to their environments.
What can be taken from the study?
The study didn’t find a direct link between early sensitivity and later ADHD symptoms, but it found links between early sensitivity and cognitive development, which influences how ADHD symptoms develop over time.
They found that early cognitive foundations can indirectly shape later outcomes.
The research offers a hopeful perspective that early differences do not shape outcomes, and the impact of nurture, especially on highly active and engaged babies, may have a greater impact than was previously thought.
"Understanding this can help tailor early environments to better support children who need it most," concluded Prof. Judith Auerbach, co-author of the paper.