Colwyn Trevarthen
Colwyn Trevarthen (born 2 March 1931 in Auckland, New Zealand) was a New Zealand–British scientist who became a professor of Child Psychology and Psychobiology at the University of Edinburgh. He studied biology at Auckland University College and Otago University, and in 1967 he researched infancy at Harvard.
Trevarthen wrote about brain development, infant communication, and emotional health. He believed that very young babies quickly learn about people and culture through interactions with others. He showed that a newborn can start a back-and-forth relationship with an adult using eye contact, smiles, and coordinated body movements, and that this relationship grows through rhythm and cooperation.
He studied how mothers and other caregivers respond to a baby’s early efforts. He used the idea of “primary intersubjectivity” to describe the first shared ways infants and caregivers understand each other through senses and movement. He argued that babies seek companionship and play, not just attachment, and that a good companion can be a parent, other family members, or any familiar caregiver who treats the baby with warmth and respect.
In later years, Trevarthen explored the musical side of babies’ communication and how music helps them connect with others.
He was a fellow of the Norwegian Academy of Science and Letters. In the 1980s, Dutch researcher Harry Biemans applied Trevarthen’s ideas to create video interaction guidance (VIG) for attachment-based therapy with mothers and babies. Stephen Seligman praised him as a highly inventive and rigorous explorer of infant development.
Trevarthen died on 1 July 2024, at the age of 93.
This page was last edited on 3 February 2026, at 02:15 (CET).