Learning to understand others’ emotions from an early age is crucial for long-term social-cognitive development. However, much remains unknown regarding potential mechanisms behind the development of early emotion understanding. Some theoretical work has proposed that language may facilitate the development of emotion understanding (e.g., Barrett, 2017), while other theoretical work argues that language should not be crucial for such development (e.g., Ekman & Cordaro, 2011). Thus, to better understand how children learn to understand emotions, what may explain some of the large individual differences observed in early emotion understanding, and what theoretical perspective may best explain early emotion understanding development, it is important to further examine the role of language in early emotion understanding development. The present studies use a novel approach to examining the relation between language and emotion understanding across early development using 1) Eye tracking, 2) Corpus analysis, and 3) Live action assessment of emotion category learning methodologies. Study 1 examined whether infant performance on a completely non-linguistic emotion categorization task related to infant language abilities. Participants were 50 infants between 15- and 18-months of age who completed the emotion categorization task using an eye tracker and whose parents provided the infants’ vocabularies. Results from this study revealed that non-linguistic emotion categorization related to vocabulary size for girls, but not for boys, providing some evidence that language may begin to relate to early emotion categorization abilities in infancy.
Study 2 investigated young children’s natural language environments and how this environment relates to children’s propensity to talk about emotion words. Nearly 2,000 transcripts of natural interactions between mothers and their 15- to 47-month-old child were drawn from the CHILDES (MacWhinney, 2000) database. Findings from this study revealed that child use of emotion language was significantly predicted by their age and their mother’s use of emotion language, but not by the child or mother’s general language complexity. These results suggest that exposure to emotion language, but not necessarily general language, may be important for children’s developing ability to talk about and understand emotions.
Study 3 evaluated whether exposure to specific emotion words would causally influence children’s ability to learn about new, complex emotions. Across two experiments, 72 3-year-old children took part in a pre-test post-test emotion category learning assessment where they were tasked with identifying which face best matched how a character would feel in a scenario. Between pre-test and post-test, children saw a face paired with a scenario and either heard an explicit emotion label, a vague emotion label, or irrelevant information. Results revealed that children learned the face-scenario associations better when given an explicit emotion label versus irrelevant information (Study 1), but vague emotion labels did not provide any advantage over irrelevant information (Study 2). Taken together, these results suggest that explicit emotion labels may be particularly important for helping young children learn about emotions.
In sum, these three studies provide some evidence that language may be important for the development of early emotion understanding. However, the strength of this evidence varied by study, suggesting that other factors such as the particular methodology being used, child age, and use of emotion language versus general language, may play important roles in understanding this relation. Altogether, these results present evidence that may be useful for more comprehensively understanding the potential mechanistic role of language in the early development of emotion understanding.