Figure 25

The surprising behavior of the SI cell can be reproduced by a leaky integrate-and-fire (IF) neuron. (a) Network schematic. The IF cell has taken the place of the SI cell in Fig. 9(a). (b) A simulation of the network in (a). Input frequencies are \(f_{1}=40\) Hz and \(f_{2}=16.357\) Hz. In the figure the membrane potential when the cell fires has been accentuated to 50 mV for illustrative reasons, although any time it passes the firing threshold (−40 mV) it is immediately reset to \(V_{\mathrm{reset}}\) (−100 mV). The SI cell behaves as in Fig. 9(b), firing in phase with input-1, alternately with input-2 (after a short transient). (c) Probability of the cell firing immediately after an input-1 pulse, as a function of the input-2 phase (time from last input-2 pulse). As in Fig. 9(c), the cell fires immediately after an input-1 pulse, if and only if the time since the last input-2 pulse lies in an interval of length 25 ms. (d) Firing rate of the cell as a function of the input-2 frequency. As in Fig. 9(d), the cell’s frequency follows that of input-2, for a range of frequencies. Dashed line in (d): diagonal