Sensitivity to musical rhythm has been found to support social development in infants. Research has shown that infants are born with a natural ability to perceive musical rhythm and can detect the beat of a song even before they are born. As they grow, they begin to develop a more refined sense of rhythm and timing, which can be enhanced through exposure to music and rhythmic activities.
According to a study published in the Proceedings of the National Academy of Sciences, engaging infants with a song provides a ready-made means of supporting social development and interaction.
Vanderbilt University Medical Center (VUMC), Marcus Autism Center, Children’s Healthcare of Atlanta, and Emory University School of Medicine researchers enrolled 112 infants aged 2 to 6 months.
The researchers observed infants’ eye movements moment by moment and discovered that the rhythm of caregivers’ singing causes infant eye movements to become synchronized or entrained to the caregivers’ social cues at sub-second timescales.
Infants were twice as likely to look to the singers’ eyes time-locked to the musical beat as would be expected by chance as early as 2 months of age, when they were first engaging with others in an interactive manner. By 6 months of age, when infants are highly experienced in face-to-face musical games and developing increasingly sophisticated rhythmic and communicative behaviors such as babbling, they were more than four times as likely to look to the singers’ eyes that were synchronized to the musical beats.
This is important because it reveals a remarkable physical coupling between caregiver behavior and infant experience. Without conscious awareness, something as simple and intuitive as caregiver singing sets in motion a whole cascade of behaviors that alters infants’ experiences.
Warren Jones
“Singing to infants appears to be such a simple act, but it is full of rich and meaningful social information,” said Miriam Lense, Ph.D., assistant professor of Otolaryngology and co-director of VUMC’s Music Cognition Lab. “We demonstrate here that when caregivers sing to their infants, they are instinctively structuring their behavior to support the caregiver-infant social bond and infant social learning.”
During testing, researchers used eye-tracking technology to track each infant’s eye movement as they watched videos of people singing to them.
“We used videos of singing rather than live singing for this study to ensure that any change in infant-looking behavior was due to the infant, rather than the singer adjusting to the infant,” Lense explained. “While watching the videos, infants could look anywhere, but we discovered that their looking behavior was not random.”
“The predictable rhythm of singing is critical for this ingrained social interaction. When we manipulate the singing experimentally so that it no longer has a predictable rhythm, entrainment is disrupted and infants can no longer successfully synchronize their eye-looking to the caregivers’ social cues” She went on to say.
Researchers confirmed their findings in another group of 6-month-old infants who watched both the original videos of singing and videos that had been jittered so that their rhythms were no longer predictable. While the infants displayed entrained eye-looking in the original videos when the singing was rhythmically predictable, when the predictable rhythm was disrupted, this time-locked eye-looking effect was no longer present.
“This is important because it reveals a remarkable physical coupling between caregiver behavior and infant experience,” said Warren Jones, Ph.D., the study’s senior author and Nien Distinguished Chair in Autism at Emory University School of Medicine. “Without conscious awareness, something as simple and intuitive as caregiver singing sets in motion a whole cascade of behaviors that alters infants’ experiences.”
“While what a caregiver expresses is important, when and how they express social cues is especially important for infant-caregiver communication,” Lense continued. “Rhythmic predictability, which is a universal feature of song, is an essential mechanism for structuring social interactions and promoting infant social development.”
According to Reyna Gordon, Ph.D., associate professor of Otolaryngology and co-director of the Music Cognition Lab at VUMC, the study emphasizes that making music is a core aspect of early socio-emotional development.
“It’s amazing that these infants are basically tracking the beat of the music with their eyes by modulating their eye contact with the singer’s eyes around the beat (or pulse) of singing,” Gordon, who was not involved in the study, said.
“These findings represent a significant advance in our understanding of the extent to which very young children are sensitive to musical rhythm, implying that innate musical ability is linked to early social engagement,” she added.
