Studying the precision of temporal neural code: some limitations of spike train distances

Since the introduction of a family of cost-based distances between spike trains by Victor and Purpura [1,2], spike train distances are widely used to study the precision of the temporal coding of neurons (see [3] for a review). Subsequently, other distances that act on convoluted spike trains have been proposed [4,5]. All of these distances involve the choice of a parameter determining the time scale at which the spike trains are compared. In general, the extent of the stimulus-specific clustering manifest in the distances between spike trains of a neuron firing in response to a set of trials of different stimuli is used to quantify the mutual information between the stimuli and the spike trains in dependence of the respective parameter. The time scale for which the maximum mutual information is obtained serves as an indicator about the precision of the temporal coding. ... ...