Hybrid analyses of neuronal spike train data for pre- and post-cross intervals in relation to interspike interval differences

Two new hybrid spike train analysis methods called( 1) pre-Cross-Interval/Interspike-Interval-Difference (pre-CI/ISID) and (2) Interspike-Interval-Difference/post-Cross-Interval (ISID/post-CI) phase plane analyses are introduced. They examine the dependency relationship between (1) the pre-cross-interval (pre-CI) and the interspike interval difference (ISID), and (2) the ISID and the post-cross-interval (post-CI) defined at a given reference spike. This allows for inferences to be made about how ISIDs in a spike train are related to the last cross interval and the next cross interval with respect to a compared spike train. Both methods were applied to simulated spike trains to display the capabilities of this new technique. The covarying relationship between the pre-CI and post-CI with respect to the ISID can be revealed as clusters of bands and points in these phase plots.