Discriminating differing types of synchrony in neural systems

We apply our previously established measure [M. Zochowski and R. Dzakpasu, Condtional entropies; phase synchronization and changes in the directionality of information flow in neural systems. J. Phys. A 37 (2004) 3823] to a pair of coupled, non-identical Hindmarsh-Rose models of thalamo-cortical neurons and demonstrate that the measure is able to detect causal interdependencies between the activity of the neurons which may remain undetected when using other methods. The discrimination between the states when these interdependencies are pronounced or abolished may be important as they may underlie different physiological states. We show the robustness of the discrimination of the measure in the presence of noise. (c) 2005 Elsevier B.V. All rights reserved.