via The Association for Psychological Science:

“The ability to trust, love, and resolve conflict with loved ones starts in childhood—way earlier than you may think. That is one message of a new review of the literature in Current Directions in Psychological Science, a journal published by the Association for Psychological Science. “Your interpersonal experiences with your mother during the first 12 to 18 months of life predict your behavior in romantic relationships 20 years later,” says psychologist Jeffry A. Simpson, the author, with University of Minnesota colleagues W. Andrew Collins and Jessica E. Salvatore. “Before you can remember, before you have language to describe it, and in ways you aren’t aware of, implicit attitudes get encoded into the mind,” about how you’ll be treated or how worthy you are of love and affection.

While those attitudes can change with new relationships, introspection, and therapy, in times of stress old patterns often reassert themselves. The mistreated infant becomes the defensive arguer; the baby whose mom was attentive and supportive works through problems, secure in the goodwill of the other person.

This is an “organizational” view of human social development. Explains Simpson: “People find a coherent, adaptive way, as best as they can, to respond to their current environments based on what’s happened to them in the past.” What happens to you as a baby affects the adult you become: It’s not such a new idea for psychology—but solid evidence for it has been lacking.

Simpson, Collins, and Salvatore have been providing that evidence: investigating the links between mother-infant relationships and later love partnerships as part of the Minnesota Longitudinal Study of Risk and Adaptation. Their subjects are 75 children of low-income mothers whom they’ve been assessing from birth into their early 30s, including their close friends and romantic partners. When the children were infants, they were put into strange or stressful situations with their mothers to test how securely the pairs were bonded. Since then, the children—who are now adults—have returned regularly for assessments of their emotional and social development. The authors have focused on their skills and resilience in working through conflicts with school peers, teenage best friends, and finally, love partners.

Through multiple analyses, the research has yielded evidence of that early encoding—confirming earlier psychological theories. But their findings depart from their predecessors’ ideas, too. “Psychologists started off thinking there was a lot of continuity in a person’s traits and behavior over time,” says Simpson. “We find a weak but important thread” between the infant in the mother’s arms and the 20-year-old in his lover’s. But “one thing has struck us over the years: It’s often harder to find evidence for stable continuity than for change on many measures.”

The good news: “If you can figure out what those old models are and verbalize them,” and if you get involved with a committed, trustworthy partner, says Simpson, “you may be able to revise your models and calibrate your behavior differently.” Old patterns can be overcome.  A betrayed baby can become loyal. An unloved infant can learn to love.