Fig. 3.

Irregular asynchronous spiking is consistent with intermittent oscillations of network activity. A: raster plots of spikes for 160 RS, 20 FS, and 20 LTS neurons, respectively. Irregular spiking for all three types of neurons is apparent by visual inspection. B: network instantaneous firing rate r(t) = ${\sum }_{i=1}^N$ r_i(t) reveals oscillations in this continuous variable. An episode of oscillation starts at around 1.75 s and lasts for about 100 ms. C: power spectrum of the network instantaneous firing rate shows an episode of elevated power between 1.75 and 1.85 s in time and around 70 Hz in frequency.