Neuronal networks possess the impressive ability to process even extremely complex and extensive information efficiently. An in-depth comprehension about the underlying mechanisms and communication paradigms between the neurons would render numerous innovations in several areas possible. To gain such an understanding it is necessary to investigate the signals inside a neuronal network. To this end, powerful methods for signal analysis are required. In this paper several concepts are introduced, which permit the detection of electrical neuronal activity. For assigning the recorded signals to specific neurons, a new, reliable technique is developed. In addition a procedure is presented, that allows such associations even in multichannel systems. The proposed methods are based on the automatic extraction of relevant signal parameters by means of multivariate data decomposition and the subsequent clustering of the determined features.