Speech, Birdsongs Learned the Same Way

June 13 2003

Human babies may learn to talk by receiving feedback from caregivers, not just by direct imitation of sounds, according to new research. Previous studies have found that many bird species use social feedback to learn songs. For example, adult female cowbirds, which do not sing, use social gestures and displays to encourage particular song qualities in young males. To determine if social interactions play a similar role for babies learning speech, Michael Goldstein and colleagues observed 8-month-old infants and mothers engaged in a play session. During the first part of the session, the scientists monitored how often infants vocalized and how the mothers reacted to each vocalization. Later, the researchers manipulated the mothers’ responses. Half the mothers were asked to react to vocalizations by smiling, moving closer, and touching their infants. Mothers in the second half were instructed to respond to infants based on predetermined schedules set by the first group. Thus, while all infants received the same amount of attention from mothers, only infants in the first group received attention synchronized with vocalizations. After analyzing recordings of the infants’ babbles, the scientists found that vocalizations from the first group became more developmentally advanced than the second group during the session, containing more syllables and faster consonant-vowel transitions. The scientists suggest that humans, like birds, require social cues to develop mature communication.

“Social interaction shapes babbling: Testing parallels between birdsong and speech” by Michael H. Goldstein, Andrew P. King, and Meredith J. West, PNAS published June 13, 2003, 10.1073/pnas.1332441100

Abstract © 2003 PNAS

Michael Goldstein is in the Psychology Department and Biological Foundations of Behavior Program at Franklin and Marshall College.