New research suggests that the earliest moments of a baby’s life—how they babble, play, and interact—may hold modest yet meaningful clues about their intelligence well into adulthood. In a landmark study published this week in the Proceedings of the National Academy of Sciences (PNAS), a team from the University of Colorado Boulder followed more than 1,000 twins from infancy to age 30, revealing that certain behaviors and environmental influences in a child’s first year can forecast cognitive abilities decades later (Neuroscience News).
The findings bear significant implications for Thai families and policymakers, underscoring the vital role of nurturing environments in the formative months of a child’s life—a period sometimes overlooked amid the push for later academic achievement. By pinpointing which early-life experiences shape lifelong cognitive development, this research highlights opportunities for Thailand’s public health and education sectors to bolster child development programs starting from infancy.
The University of Colorado-led team tracked 1,098 twins born in Colorado, measuring behaviors as early as seven months old, including vocalization, ability to stay focused on tasks, and a preference for new rather than familiar toys. The results show that simple cognitive tests conducted in infancy can predict as much as 13% of the variance in adult cognitive scores at age 30, a striking result given the vast array of life experiences that follow early childhood. Environmental factors in the first year alone accounted for approximately 10% of the differences in adult intelligence among the study group.
Notably, the strongest early indicators turned out to be “novelty preference” (preference for new toys) and “task orientation”—traits that are not only observable in babies around the world, but also align with traditional Thai parenting values, such as encouraging curiosity and patience in young children. Despite the modest predictive power, the results send a strong message to parents, educators, and policymakers: the experiences and environments provided to children before preschool can have lasting consequences.
Genetic influences, as expected, also played a major role. By comparing identical and fraternal twins, researchers found that genetics accounted for almost half of the variation in cognitive scores by age 30. Yet the intriguing revelation, emphasized by the lead researchers, was the measurable and enduring impact of environment—especially in the first two years of life—before formal education or structured enrichment activities come into play.
The research applies twin and genomic analyses to distinguish between nature and nurture influences. Even as the predictive power of environment diminished with age (as genetic influences grew stronger), its early imprint remained, raising important questions about when, and how, to intervene for children who may be at risk of falling behind cognitively.
“The most exciting finding was that 10% of the variability in adult cognitive ability was explained by environmental influences before year one or two,” said the study’s lead author, an assistant research professor at the Institute for Behavioral Genetics, in the university’s official statement. “This suggests that even the pre-preschool environment matters” (University of Colorado).
The senior co-author, a professor of psychology and neuroscience, emphasized the implications not just for school performance, but for lifelong brain health: “Cognitive aging is a life-long process, not just something that begins in mid-life. Certain interventions, like strong educational foundations in early life, could help maximize what people are capable of and help them keep that cognitive gas in the tank for as long as possible” (Neuroscience News).
For Thailand, a nation where public debate often focuses on boosting academic test scores and university quotas, this research is a reminder that the roots of intelligence run far deeper and start much earlier. While traditional values in some Thai communities revere formal instruction in reading, mathematics, and languages in the preschool years, this study suggests that unstructured play, gentle stimulation, and sensitive caregiving in infancy may be just as critical to eventual academic and professional success.
Moreover, Thailand’s demographic changes—marked by falling birth rates and an aging population—make smart investment in early childhood development all the more urgent. Existing national policies, such as the Early Childhood Act B.E. 2562 (2019), aim to provide universal development support for children from birth to six years, yet the latest research points to an even earlier focus, starting from the first months of life (Thailand Early Childhood Act).
Looking more closely at the data, the authors stress that infant behaviors like novelty preference and task orientation are not fixed predictors: environment and later experiences still play crucial roles. Simple interventions—such as responsive caregiving, exposure to stimulating environments, and positive early interactions—can maximize a child’s innate potential.
Genetic analysis was another innovative aspect of this work. The researchers used “polygenic scores,” which aggregate thousands of small genetic influences, to predict intelligence. These scores, informed by DNA data from nearly a million individuals worldwide, showed that people with higher predicted genetic predispositions for intelligence—derived from their infancy—performed as expected three decades later. This adds to the growing body of global evidence that genes and environment are deeply intertwined in brain development (PNAS).
For Thai families, these findings may prompt reflection on traditional child-rearing practices, which often emphasize social harmony, obedience, and respect, sometimes at the expense of open-ended play and curiosity. Public health campaigns in Thailand have in recent years highlighted the importance of the “1,000 Day Window”—from conception through age two—as a uniquely sensitive period for health and learning. The new research lends fresh weight to these policy pushes, supporting increased government spending and community programs to provide enriched environments in the earliest years.
The study’s approach, a combination of long-term twin tracking and cutting-edge genetic analysis, represents a major advance in understanding how intelligence develops—and underscores the need for both universal and targeted interventions, especially for families in poverty or rural areas, where stimulation and enrichment may be lacking. In Thailand, disparities in access to early education and parental support services have repeatedly been shown to perpetuate educational gaps later in life (UNICEF Thailand).
Historically, Thai childcare was embedded in extended families, with grandparents and relatives deeply involved in raising infants—providing a rich linguistic and social environment. As family structures shift toward nuclear households and the workforce participation of mothers increases, these traditional supports can fade. National childcare centers, which often focus on ages three and above, may miss the critical first year where the latest science suggests interventions are most valuable.
Looking ahead, the authors of the PNAS study urge ongoing research and practical innovation. They stress that while infant cognitive assessments are not destiny, they are a valuable tool for identifying children who may benefit from extra support. The study also raises complex questions about genetic testing and privacy—issues that will require culturally sensitive guidelines if, for instance, schools or clinics begin using polygenic scores.
For policymakers in Thailand, the actionable message is clear: prioritize early childhood programs that begin in the first months of life, ensure universal access to parental education and support, and promote play-based learning environments that encourage curiosity, attention, and exploration. Expanding maternity and paternity leave, providing home visiting programs for new parents, and reducing economic barriers to healthy early development should be at the forefront of national strategy.
For parents and caregivers, the recommendation is subtler but profound: everyday play, responsive attention, and nurturing care in the first year matter more than formal instruction. Creating environments where babies feel safe, loved, and encouraged to explore new things can have a lifelong impact—potentially influencing not only how children perform in school, but how their minds age over decades.
As Thai society weighs the future of its children, this research serves as both a warning and an opportunity. The earliest months and years are not simply a prelude to education—they are the foundation upon which cognitive, emotional, and social capacities are built. By acting wisely and early, Thailand can give its next generation the best possible start in life—for school, work, and healthy aging.
For more background, readers can explore the full study summary at Neuroscience News and the original research at PNAS.