The understanding of interacting dynamics is important for the characterization of real-world/nnetworks. In general real-world networks are heterogeneous in the sense that each node of the/nnetwork is a dynamics with di erent properties. For coupled non-identical dynamics symmetric/ninteractions are not straightforwardly de ned from the coupling strength values. Thus, a challenging/nissue is whether we can de ne a symmetric interaction in this asymmetric setting. To address this/nproblem we introduce the notion of the coupling impact. The coupling impact considers not only/nthe coupling strength but also the energy of the individual dynamics which is conveyed via the/ncoupling. To illustrate this concept, we follow a data-driven approach by analyzing signals from pairs/nof coupled model dynamics using two di erent connectivity measures. We nd that the coupling/nimpact, but not the coupling strength, correctly detects a symmetric interaction between pairs of/ncoupled dynamics regardless of their degree of asymmetry. Therefore, this approach allows to reveal/nthe real impact that one dynamics has on the other and hence to de ne symmetric interactions in/npairs of non-identical dynamics.

They acknowledge funding from the Volkswagen foundation and support by the Spanish Ministry of Economy and/nCompetitiveness (Grant FIS2014-54177-R). This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 642563 (R.G.A.) and/nCERCA Programme/Generalitat de Catalunya (R.G.A).