Motherese in Interaction: At the Cross-Road of Emotion and Cognition? (A Systematic Review)

Abstract

Various aspects of motherese also known as infant-directed speech (IDS) have been studied for many years. As it is a widespread phenomenon, it is suspected to play some important roles in infant development. Therefore, our purpose was to provide an update of the evidence accumulated by reviewing all of the empirical or experimental studies that have been published since 1966 on IDS driving factors and impacts. Two databases were screened and 144 relevant studies were retained. General linguistic and prosodic characteristics of IDS were found in a variety of languages, and IDS was not restricted to mothers. IDS varied with factors associated with the caregiver (e.g., cultural, psychological and physiological) and the infant (e.g., reactivity and interactive feedback). IDS promoted infants’ affect, attention and language learning. Cognitive aspects of IDS have been widely studied whereas affective ones still need to be developed. However, during interactions, the following two observations were notable: (1) IDS prosody reflects emotional charges and meets infants’ preferences, and (2) mother-infant contingency and synchrony are crucial for IDS production and prolongation. Thus, IDS is part of an interactive loop that may play an important role in infants’ cognitive and social development.

Análise comparativa das vocalizações iniciais de bebês prematuros e a termo, com e sem risco ao desenvolvimento

“…This may have occurred due to advancement in the language skills of infants in Phase 2, as predicted by several studies (6)(7)(8) . Mothers tend to adjust the speech directed to their children according to their age, cognitive skills, and linguistic level (14) . In a recent study (21) , the authors observed, based on the analysis of homemade videos, that the use of motherese reduces over time, more significantly between the first and second six months of life of infants.…”

“…The prosodic contours of motherese, from their peculiar characteristics, are designed to facilitate the understanding by infants and assist in language acquisition, stimulating their responsive capacity (14) . Therefore, the fact that infants are increasing their language skills may explain the mothers' lesser focus on this support.…”

“…Furthermore, the correlations between the second IRDI and the mothers' vocalizations using IDS and between the third IRDI and the total number of infants' vocalizations show that the contingency and synchrony of mothers with infants are crucial for the production and extension of motherese, because according to the infants' reaction, there is an increase in the use of IDS from the part of the mothers, and such contingent feedback from the infants makes them more attractive, which in turn increases the quality of motherese (14) .Therefore, the use of motherese from the part of the mothers is as important as the infant's reaction to it.…”

“…Some authors (14) have emphasized that motherese reflects an interactive loop between infants and caregivers, in such a way that the response of each person may increase the initial stimulation of the other partner, which may explain the correlation found between the larger number of infants' vocalizations and the fourth indicator. This interactive loop is supported by the emotional charge of the affective level, affecting the cognitive level, attention, learning, and the construction of intersubjective tools, such as joint attention and communicative skills (14,22) . Phase 1 indicators contemplate communication in the mother-infant dyad.…”

“…Therefore, motherese supports the affective and verbal communication of developing infants and can arouse the attention to speech that is directed specifically to them, with content and form that are adapted to them (13) . These continuous adjustments of mothers to their babies can result in facilitation of exchanges and interactions, with positive consequences for the sharing of emotions and language acquisition (14) . Importance of the early relationships in the context of child development is evident; therefore, the monitoring of infants and their parents is essential for early risk detection.…”