This volume contains the proceedings of a day conference on coupled neuronal oscillators (CNO '90, London), an important aspect of neural network research, which may hold the key to a clearer appreciation of the manner in which neural networks can control complex behaviour. The contributors to the conference looked at the physiological properties of neurons in terms of electrochemical features, using these to consider possible directions for future research. The papers cover a range of areas, including an introduction to non-linear oscillators, bifurcating neurons, the modelling of cardiac rhythm, gamma oscillations, association and consciousness, and a model for low threshold oscillations in neurons. The papers also include new explanations and models of the phenomena of coupled oscillatory neural assemblies, ranging from those for the multi-phasic response of single neurons, to possible models of image segmentation.