Fig. 7.

Spike triplets detected by the JPM method.a, The JPTH of a spike triplet (3, 2, 0). Summed pixels in the x- and y-axes are also shown.b, “Expected” JPTH, constructed on the assumption that triplets are random coincidences of spike doublets (see Materials and Methods). c, The excess number of triplets expressed as the difference between the observed and expected JPTHs. Significant pixels (Fisher's exact probability test) are framed inboxes. d, Vector representation of 3, 2, 0 sequences extracted by the template-matching method. Note that the latencies of the triplets match the significant pixels in the JPM.e, JPM maps constructed using three different pixel sizes (5, 6.7, and 10 msec) from the original and 100 shuffled surrogates (same original data sets shown in Fig. 6). The number of significant pixels in the surrogate JPMs is expressed as a percentage of the significant pixels in the original JPM. Colorbars, Number of events.