Communicative gestures in 7–12-month infants: a phylogenetic comparative approach

Different methodologies applied in human and non-human primate studies limit the comparisons that can be made. The early communicative gestures of 10 children between 7 and 12 months were analysed using a descriptive approach usually found in non-human primate studies. Silent-visual gestures were the most used, followed by contact and audible gestures. The use of the different modalities of gestures did not differ with the infants' gender or age, unlike findings from studies on great apes. However, signalers chose different gestural sensory modalities according to the attentional state of the audience, similarly to other great apes: more silent-visual gestures were used when the visual attention of the recipient is present. Thus, intentionality in gestural communication was not only detected through behavioural cues but also supported by the use of different strategies according to the attentional state of the recipient. Importantly, this study suggests that human infants consider the attentional state of their partners during communication earlier in ontogeny than previously thought.