Fig. 12.

Effect of synchrony on firing rate, spike variability, reliability, and precision. In all experiments shown, synchrony was increased by reducing the value of τ_b for a fixed value of λ_b (2 Hz), and scaling up $\overline{R}$ correspondingly to maintain the same mean rate of compound AMPA–NMDA excitatory conductance transients (300 Hz). A, Effect of synchrony on mean firing rate. a, In a fast-adapting neuron, firing rate increases with increasing synchrony. b, In a regular spiking neuron, the firing rate decreases with increasing synchrony. B, Effect of synchrony on spike timing variability in a regular-spiking neuron. Both Fano factor and CV of interspike intervals are increased by synchronous stimuli, to much higher values than for uncorrelated Poisson stimulus trains (indicated by dotted lines) and to values within the range of those commonly observed in vivo. Results are from 30 trials with resynthesized timings of unitary events in one cell. C, Increasing synchrony increases reliability (a) and reduces spike time jitter (b) in a regular-spiking cell (10 trials).