| Near-zero phase delays (<2 ms) have been observed in synchronized oscillatory activity by using cross-correlation histograms (CCHs). These time delays can be stimulus specific and highly reliable, yet invisible in the underlying spike trains. We present a stochastic model for the parallel firing activity of multiple neurons that offers a possible explanation for these phenomena and that focuses particularly on asymmetric CCH peaks. The model links the features of oscillatory CCHs to the properties of the underlying processes and to their auto-correlation functions. It predicts the shape of the CCHs from the auto correlations and thus offers the possibility of analysing correlations between the processes on the basis of statistics of individual spike trains. We apply the model to spike trains recorded in cat visual cortex under visual stimulation. |
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