Precursors of Sign Use in Intersubjectivity and Imitation (PSUII)

In earlier work we have explored the human capacity to engage in sign use, comparing different semiotic resources with respect to their developmental and evolutionary origins. In this project, we will realise a set of experiments with non-human primates and pre-verbal children, in order to throw light on the necessity for mastering imitation and intersubjectivity in order to attain sign use.

In previous collaborative research, we have explored the human capacity to engage in sign use, comparing different semiotic resources with respect to their developmental and evolutionary origins. We concluded that imitation does not involve sign use proper, but constitutes a natural first step to it, through volitional control and differentiation: between means and ends and between self and other. Furthermore, imitation and intersubjectivity (the ability to share experiences with others) appear to be very closely related. Finally, gestures (constituting intentional communicative signs: S uses X to mean Y for Z) are likely to be the first semiotic resource to clearly “cross over” the threshold of sign use in both evolution and development.
A number of questions remain, of which we will focus on the following:
• Is a certain capacity for imitation a necessary prerequisite for the emergence of sign use? And if so, how does the transition between imitation and sign use take place?
• Or can an environment in which intersubjectivity is stimulated independently of imitation lead to sign use?
• Finally, can a form of sign use – understanding the representational nature of pictures – emerge independently of both imitation and intersubjectivity?
We propose to conduct a set of experiments with non-human primates (above all chimpanzees and orang-utans), alongside with similar experiments involving pre-verbal children, in order to throw light on these issues.