— As non verbal cues are crucial for communication hence long-life learning. Here we focus on the advantages of using rhythmic feedback as implicit marker during interactions. Through two different experimental studies with naive subjects and robots we show the utility of using and modelling rhythmic adaptation but also desynchronisation. We found out that rhythmical adaptation and bidirectional entrain-ment are imperative to reach synchronisation. Yet, we discovered that desynchronisation can be perceived as an implicit marker and hence be used to predict an issue in the interaction, making this interaction more pleasant. This shows that rhythmic cues such as synchronisation and desynchronisation are important elements for the development of interaction capabilities. Index Terms— Synchronisation, Entrainment effect , bidirectional interactions, non verbal communication , interaction capabilities.