Figure 16

The IB burst timing depends on the SI spike timing. (a) Definition of variables plotted in (b), (c). IB-SI denotes the time elapsed from the beginning of an IB burst until the next SI spike. IB-IB denotes the time from the beginning of one IB burst until the beginning of the next one. (b) Interburst interval of the IB cell as a function of the timing of the (unique) SI spike that falls inside the interval, for a simulation of the FS-SI-IB network with 51 Hz input. The timing of the IB cell (“IB-IB”) seems to be approximately determined by the timing of the SI spike (“IB-SI”). In this simulation the SI cell fires only between approximately 16 and 30 ms. (c) Same as (b), for 62 Hz input (and slightly faster h-current kinetics—see Appendix D.1). Almost all data points fall approximately on one of three lines, suggesting that the timing of the IB cell depends on the SI timing and some other variable that takes finitely many values