Characterization of non-linear dynamics in rat cortical neuronal networks

In this paper we report on the evidence for low-dimensional deterministic chaos in extra-cellular recordings of mature rat cortical cells in culture medium. In general, the available data sets are relatively short and are heavily contaminated by noise making conclusive interpretations of chaotic behaviour difficult to ascertain. In this study we describe two analysis techniques used to detect chaotic behaviour, namely return map construction and Lyapunov exponent calculation. Results show that both methods indicate the presence of chaos which is consistent with other recent studies that have also suggested chaotic behaviour in cultured cell networks. In addition, the use of these two independent analysis techniques provides more rigorous evidence for the existence of chaotic behaviour in cultured cell networks since previous studios have relied solely on the method of return maps.