Genes Influence What Babies Look at: Study from Uppsala and Karolinska Shows. Researchers found that at five months old, infants tend to focus on either faces or objects like cars and phones due to their genes. This suggests that genes play a role in shaping how babies see and learn about their surroundings. The study is published in Nature Human Behaviour.
How we use our eyes to look around influences what we pay attention to and learn. A recent study looked at over 500 sets of baby twins to understand whether they prefer looking at faces or non-social objects.
Ana Maria Portugal is a postdoctoral researcher and the study’s first author. Said, “Our results suggest that even before infants can influence and choose their environment by pointing, crawling, or walking, they create their own unique perceptual experiences by systematically looking more at social or non-social objects, preferences that genetic differences between children can largely explain.”
Researchers used a baby-friendly eye tracker to see where children look. The study revealed that babies’ liking for looking at faces is primarily because of their genes, not their family environment. Babies who gazed more at faces at five months old tended to have a more extensive vocabulary by their second year. Early-looking habits can be connected to later development.
How babies look at things can affect how parents interact with them. If an infant prefers looking at faces, it can influence how parents behave. However, focusing on non-social objects is okay; it’s also crucial for brain development, according to Portugal. The study, part of the Baby Twins Study Sweden, followed twins from five months to three years, using child-friendly methods at the Karolinska Institutet Center for Neurodevelopmental Disorders.
Portugal discovered that genetically identical twins had more similar-looking preferences than fraternal twins. If one identical twin preferred non-social objects, the other twin likely had the same preference. Fraternal twins, who share only 50% of their genes on average, had less similar-looking preferences. The study also explored whether early visual preferences could predict later language development and if they were linked to autism-related behaviors in childhood. The researchers also investigated gender differences in facial preference.
Terje Falck-Ytter, Professor at the Department of Psychology at Uppsala University and principal investigator in the BATSS study, notes, “Our results indicate that face preference in infants is not strongly associated with social communication ability later in childhood. We also found no difference between boys and girls regarding preference for faces versus non-social objects.”
“Moreover, our data showed that the genes which influence facial preference are not the same as those involved in eye contact – that is, whether infants looked primarily at the eyes or the mouth when looking at a face. It’s fascinating that two basic social behaviours like looking at faces and looking at eyes have different genetic and probably evolutionary bases,” adds Professor Falck-Ytter.
The research project has secured financial support from various entities, including Riksbankens Jubileumsfond, the Knut and Alice Wallenberg Foundation, and the European Union.
This study underscores the significance of genetic factors in influencing infants’ visual preferences for faces or non-social objects. The observed correlations between early visual preferences, language development, and later behaviors provide valuable insights into the intricate connections between genetics, visual perception, and developmental outcomes in infancy.
Journal reference:
- Portugal, A.M., Viktorsson, C., Taylor, M.J. et al. Infants’ looking preferences for social versus non-social objects reflect genetic variation. Nature Human Behaviour. DOI: 10.1038/s41562-023-01764-w.