This study that says babies understand that a different language is being spoken solely from watching visual cues from the time they are born until 8 months of age. After 8 months they lose the ability to differentiate. The Washington Post reports,
Petitto said the study has “important implications,” because “it supports the belief that the brain can use multiple cues in language processing and suggests that multiple cues in teaching languages can be beneficial.”
I think this study could have important implications for children with Austism Spectrum Disorder or learning disabilities which involve difficulty in reading visual cues. It reinforces the importance of visual cues in helping children learn language.
For children who have difficulty learning through visual cues, sign language could be advantageous because the child is learning a second language which is heavily reliant on visual cues, strengthening their competencies in this area. Not all children who have difficulty reading visual cues (e.g non-verbal communication becomes increasingly more subtle as we grow older) will be identified by 8 months. Adopting a blanket approach to teaching children second languages and/or signing may be beneficial.