No abstract

The present study examined the influence of infant visual cues on maternal vocal and facial expressiveness while speaking or singing and the influence of maternal visual cues on infant attention. Experiment 1 asked whether mothers exhibit more vocal emotion when speaking and singing to infants in or out of view. Adults judged which of each pair of audio excerpts (in view, out of view) sounded more emotional. Face-to-face vocalizations were judged more emotional than vocalizations to infants out of view. Moreover, mothers smiled considerably more while singing than while speaking to infants. Experiment 2 examined the influence of video feedback from infants on maternal speech and singing. Maternal vocalizations in the context of video feedback were judged to be less emotional than those in face-to-face contexts but more emotional than those in out-of-view contexts. Experiment 3 compared six-month-old infants' attention to maternal speech and singing with audio-only versions or with silent video-only versions. Infants exhibited comparable attention to audio-only versions of speech and singing but greater attention to video-only versions of singing. The present investigation is unique in documenting the contribution of infant visual feedback to maternal vocal emotion in contexts that control for infants' presence, visibility, and proximity.

The origin of the Western preference for consonance remains unresolved, with some suggesting that the preference is innate. In Experiments 1 and 2 of the present study, 6-month-old infants heard six different consonant/dissonant pairs of stimuli, including those tested in previous research. In contrast to the findings of others, infants in the present study failed to listen longer to consonant stimuli. After 3 minutes of exposure to consonant or dissonant stimuli in Experiment 3, 6-month-old infants listened longer to the familiar stimulus, whether consonant or dissonant. Our findings are inconsistent with innate preferences for consonant stimuli. Instead, the effect of short-term exposure is consistent with the view that familiarity underlies the origin of the Western preference for consonant intervals.

Music is part of an infant's world even before birth, and caregivers around the world sing to infants. Yet, there has been little research into the musical abilities or preferences of infants younger than 5 months. In this study, the head turn preference procedure used with older infants was adapted into an eye-movement preference procedure so that the ability of 2-month-old infants to remember a short melody could be tested. The results show that with minimal familiarization, 2-month-old infants remember a short melody and can discriminate it from a similar melody.

Little is known about infants' perception of cross-modal cues to identity, but the importance of recognizing familiar individuals makes it likely that this skill would be evident early in life. Infants 6-8 months of age were tested on their ability to link dynamic cross-modal cues to the identity of unfamiliar speakers and singers. After exposure to speech or singing, infants watched two silent videos, one featuring the previously heard speaker or singer. Infants looked significantly longer at the video of the person heard previously, which indicates that they can match auditory and visual cues to the identity of unfamiliar persons.