DYNAMICS OF FUNCTIONAL COUPLING IN THE CEREBRAL-CORTEX - AN ATTEMPT AT A MODEL-BASED INTERPRETATION

Electrophysiological studies of cortical function on the basis of simu ltaneous, separable multi-neuron recordings reveal interactions betwee n cortical neurons which strongly depend on the stimulus and behaviora l context. Moreover, these interactions exhibit dynamics on several di fferent time scales, with time constants of modulation as low as tens of milliseconds. Possible mechanisms underlying such dynamic organizat ion of the cortical network were investigated by simulations and analy tic approaches. We review results from these different studies, concen trating on a comparison of the correlation dynamics in real cortical a ctivity and in various neural network models. In particular, we discus s the influence of global network activity on the functional coupling between neurons embedded in such networks.