Neurotherapy is a complementary treatment used in various disorders of the central nervous system (CNS), such as epilepsy and attention deficit hyperactivity. The method is subsumed under the behavioral medicine, and is considered to be an operand conditioning in psychological terms. However, its mechanisms are not well understood yet. In this article, we discuss the drawbacks of a conventional control engineering approach to analyze such a complex process (i.e. EEGbiofeedback) which elicits alterations on a complex system (i.e. CNS). Based on the results and observations we gained on the course of our clinical studies with epilepsy patients, we discuss the plausibility of a general systems theoretical approach to the neurotherapy process. Using the concepts of complexity, open systems, selforganization, and self-regulation, we underline the necessity of a systems theoretical framework. We show the analogies of the EEG-biofeedback process to other operand conditioning experiments explained via the methods of the synergetics.