Imitation of words and actions across cultures

Humans imitate in a unique way. They imitate selectively, that is, they imitate intentional actions at a higher rate than accidental ones. At the same time humans tend to faithfully imitate actions that do not seem to be relevant to an end goal. Selectively imitating intentional actions allows us to learn efficiently from others, while faithful imitation makes it possible to acquire complex cultural conventions without immediately understanding the contribution of each of its components. Recent studies suggest that this unique way of imitating is universal across cultures and enables humans to develop complex cultural practices that set them apart from other species. The evidence so far, however, is almost exclusively based on studies about the imitation of actions, while little work has been done on the imitation of language. Language is arguably humanity's most important cultural product and unlike instrumental actions that are restricted by the laws of physics, language is a fairly arbitrary system of conventions and thus more prone to cross-cultural variance. Claims about the cultural universality in imitation learning thus need to be supported by data from verbal imitation. The present work addresses this point in four studies. The first three studies tested children's imitation of adjectives in different contexts across three different cultures: a small indigenous community in Mexico and two western large-scale societies. In various verbal imitation tasks we found cross-cultural differences. We propose that these differences are due to differences in the amount of time spent in dyadic caregiver-child interaction in indigenous and western culture. Further, the data suggest that this cultural variation arises from the fact that humans across cultures in both verbal and instrumental tasks imitate selectively when the function of an element is transparent to them. When its function is opaque they do the safe thing: faithfully imitate. This account is tested in study four. In an instrumental task adults and children imitated faithfully when the function of the actions performed was opaque, but not when they were transparent. This allows us to propose that the cross-cultural differences we observe are thus due to differences in experience that make different aspects of language use more or less transparent to learners.