Figure 8. A facilitating connection onto a sparsely spiny, burst firing neocortical interneurone without release-independent depression.

The postsynaptic interneurone was similar to those described previously (Thomson et al. 1995; Deuchars & Thomson, 1995). In this pyramid-interneurone connection, facilitation is maintained throughout a 5 spike train (A). B, facilitation of the average second EPSP relative to the average first EPSP (grey traces) is greatest at the shortest interspike intervals. However, larger first EPSPs are followed by less facilitated second EPSPs (D) than are first spike failures (C). Both facilitation and release-dependent depression are therefore involved.