Language Familiarity Affects Voice Discrimination by Seven-month-olds

Three experiments using the Visual Fixation Procedure were carried out to investigate Dutch-learning 7-montholds’ ability to discriminate voices in a familiar versus unfamiliar language. In all three experiments, infants were habitutated to 3 female voices in one language and then tested on a new female voice in the habituated language (Voice-Change Trials) and a new female voice in a new language (Voice-Plus–Language-Change Trials). In Experiment 1 (Dutch versus Japanese) and Experiment 2 (Italian versus Japanese), infants dishabituated to VoicePlus-Language-Change Trials. But only Dutch-habituated infants in Experiment 1 dishabituated to Voice-Change Trials. A third experiment using backwards speech ruled out the possibility that the Dutch speakers were simply more variable in voice quality than the Italian and Japanese speakers. These results replicate earlier work demonstrating that infants can discriminate rhythmically-distinct languages. In addition, this study provides the first ever evidence that infants are more sensitive to voice changes in their native language than in an unfamiliar language.