One of the most astounding things about infants is that those tiny, sniggling, helpless lumps of flesh eventually grow into full-sized humans that vote, have sex, and get into arguments on the internet. While pediatricians can predict physical attributes like adult height in infants with relative accuracy, predicting what kind of people these kids will be like is a more mysterious, weird, and interesting process. According to the psychology literature, it’s a nonstarter to talk about “infant personality,” since personality is something that arises from the way a child meets the world — family, friends, culture, and beyond. As all-star psych writer Christian Jarrett reports on BBC Future, clues to your adult personality were showing up even before you could talk.
If you’re trying to get at the psychology of the tiniest humans, what you’re looking at is temperament, which researchers say is “the initial basis for dispositions and orientations toward others and the physical world and for shaping the person’s adaptations to that world.” To put it roughly, temperament is an expression of your genes, a set of biological predispositions. Personality is an expression of how your temperament interacts with the world. A new paper from Russian researchers Helena Slobodskaya and Elena Kozlova is a case study in that regard. The researchers asked parents to rate their infants’ temperament at 7 months, on average, and then returned eight years later for ratings on the Big 5 personality traits like extraversion, emotional stability, and conscientiousness. According to the parents’ ratings, the infants who showed greater “surgency” (that is, they tend to get excited about things) scored lower on neuroticism — indicating that they were more emotionally stable. Infants who scored higher on regulatory capacity (like being able to resist the temptation of a toy) scored higher on conscientiousness as eight-year-olds — meaning they were, Jarrett quips, more likely to clean their rooms. But not everything was linear: Contrary to what you might assume, infants who smiled and gurgled lots didn’t score higher on extroversion as they grew up.
But while temperament is predictive, it’s not destiny. A 2007 Czech study puts that point into further relief. Researchers took the recorded temperaments of kids from 12 to 30 months old and made a personality follow-up 40 years later. Of all the qualities of toddler temperament that researchers assessed, only one had a clear link into adulthood: toddler “disinhibition” correlated with adult extraversion and self-efficacy, or the belief that you’re capable of doing things. In other words, unself-conscious kids grow into assertive adults. “We suggest that a modest connection between child temperament and adult personality characteristics is due to the fact that personality formation is largely influenced by social factors,” the authors write.
There’s a bunch of life lessons to be drawn out from temperament research. It shows how the self isn’t a singular entity. To borrow from Cambridge University psychologist Brian Little, each of us has at least three selves — the “biogenic,” or what your genes dispose you to; the “sociogenic,” or what relationships and culture tell you; and the “idiogenic,” or the pursuits that you arrange your life around. Personality is a collision between your genes, your upbringing, and what you discover in life. To me, the idiogenic is the most liberated part of self, since it’s the aspect that isn’t an inheritance from your parents’ genes or culture’s norms. Maybe even more-so than your genes, your projects are uniquely yours.