papers available, hardcopies only. ------------------------------------------------------------------------ GENERAL ASYMMETRIC NEURAL NETWORKS AND STRUCTURE DESIGN BY GENETIC ALGORITHMS Stefan Bornholdt Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 2000 Hamburg 52 Dirk Graudenz Institut f\"ur Theoretische Physik, Lehrstuhl E, RWTH 5100 Aachen, Germany. A learning algorithm for neural networks based on genetic algorithms is proposed. The concept leads in a natural way to a model for the explanation of inherited behavior. Explicitly we study a simplified model for a brain with sensory and motor neurons. We use a general asymmetric network whose structure is solely determined by an evolutionary process. This system is simulated numerically. It turns out that the network obtained by the algorithm reaches a stable state after a small number of sweeps. Some results illustrating the learning capabilities are presented. [to appear in Neural Networks] preprints available from: Stefan Bornholdt, DESY-T, Notkestr. 85, 2000 Hamburg 52, Germany. Email: [log in to unmask] (hardcopies only, all rights reserved) ------------------------------------------------------------------------