Figure 10.
During the fast oscillations, inhibitory and excitatory events do not have a specific temporal relationship to each other. A, Example analysis for an individual neuron in our database. Left, sample excitatory (red) and inhibitory (blue) event trains identified simultaneously from an intracellular recording at intermediate voltage depolarization (approximately −40 mV, see Fig. 5B). Middle, coherence between the excitatory and the inhibitory spike trains in A. Right, cross-correlation function (obtained from the coherence in B) between excitatory and inhibitory events in A. B, Population results for the coherence (left) and for the coherency (right) between excitatory and inhibitory events averaged over the population (n = 10). Significant coherence and nonsignificant coherency in the β/γ band indicate the absence of a specific temporal relationship between excitation and inhibition during fast oscillations. C, Parallel analysis using inhibitory trains extracted from depolarized records and excitatory trains extracted from hyperpolarized records, and constructing an event-field-event measure to evaluate if they have a consistent phase relationship to the LFP (see Materials and Methods). Event-field-event coherence (left) and coherency (right) parallel the result in B (n = 10). In all panels, shading indicates the 95% CI of the estimate. Red dashed lines mark the upper 95% CI under the hypothesis of independence.