Language Discrimination Response Latencies in Two-month-old Infants

There is increasing evidence that infants can discriminate native and non-native speech from an early age. Prosody may be essential to this ability. In this paper, we assess the amount of linguistic information needed by two-month-old infants to recognize whether or not a sentence belongs to their native language. We conducted a cross-linguistic study of French and American 2-month old infants, measuring the latency of the first ocular saccade toward a loudspeaker playing short French and English utterances. The results indicated a significant interaction between the infants' nationality and the language of the stimuli. Infants oriented faster to their native language, even when the utterances were short (1.2 s mean). However, eliminating the prosodic organization (scrambled words condition) of the sentences, neutralized the effect. The results confirm that prosody plays a predominant role when young infants process continuous speech, and that short utterances are sufficient to recognize a language as long as prosodic information is present and coherent across the utterance.