Bilingualism Modulates Infants’ Selective Attention to the Mouth of a Talking Face

Abstract

Bilingual infants succeed at learning their first two languages. What adaptive processes enable them to master the more complex nature of bilingual input? One possibility is that bilingual infants take greater advantage of the redundancy of the audiovisual speech that they usually experience during social interactions. Thus, we investigated whether bilinguals’ need to keep languages apart increases their attention to the mouth as a source of redundant and reliable speech cues. We measured selective attention to talking faces in 4-, 8-, and 12-month-old Catalan- and Spanish- monolingual and bilingual infants. Monolingual data paralleled previous findings, whereas bilingual data suggested an emerging move away from the eyes beginning earlier in development, followed by increasing attention to the mouth from 8 to 12 months of age. Thus, bilingual infants exploit the greater perceptual salience of redundant audiovisual speech cues earlier and longer than monolinguals to support their dual language acquisition processes.

Multisensory Processes: A Balancing Act across the Lifespan

“…Seeing the speaker’s mouth can increase the intelligibility of the auditory signal by 15 dB [1]. This ability to extract speech information from visual cues begins in infancy when infants start babbling and need to learn native speech forms, when they have to disambiguate unfamiliar speech, and when they are learning two languages [2,3]. Extending this further, deaf individuals can learn to watch mouth movements to understand speech by lip reading, which results in extensive cross-modal plasticity within regions of the cerebral cortex [4].…”

The development of spontaneous sound-shape matching in monolingual and bilingual infants during the first year.

“…Bilingual exposure has been shown to modulate infants' attention to cross-modal information (e.g., Pons, Bosch, & Lewkowicz, 2015); therefore, it is possible that bilingual infants exhibit matching preferences earlier than monolinguals. However, it is also relevant to consider here that native Basque-speaking adults demonstrate a stronger bouba-kike effect than native Spanish-speaking adults (Pejovic, Molnar, Yee, Martin, 2015).…”

Infants’ Looking to Surprising Events: When Eye-Tracking Reveals More than Looking Time

“…Both measures can be collected simultaneously, but pupillometry gives more fine-grained, time-locked reactions from individual infants (see also [20]). Future studies should consider designs that allow for the analysis of such measures, which may further shed light upon infants’ precise reasoning processes.…”

“…Increasingly, both infant and adult research studies measure other types of gaze information, asking how looking to specific locations reveal more subtle measures of cognitive ability. Such techniques have been used to explore implicit theory-of-mind [7–10], perceptual categorization abilities [11–15], as well as many other aspects of cognitive and perceptual processing (e.g., [16–20]). In the present report, we focus on a research domain in which these advanced eye-tracking techniques have not yet been applied: Infants’ understanding of surprising sampling events in procedures that measure inferential reasoning, and which have garnered significant attention in the cognitive development literature in recent years [21–23].…”