The aim of the present study is to analyse conscious and unconscious processes using the paradigm of listener-speaker in neurotypical children aged 6 and 9 years old. The speaker was always a child; the listener was a human or a robot, i.e., a small robot which reacts to speech expression by nodding only. Physiological data, i.e., heart rate, as well as behavioral data, i.e., number of words in addition with reported feelings, were considered. The results showed that (1) the heart rate was higher for children aged 6 years old than for children aged 9 years old when the listener was the robot; (2) the number of nouns and verbs expressed by both age groups was higher when the listener was the human. The results are consistent with the idea that conscious and unconscious development would not only depend on natural environments but also on artificial environments represented by robots.