How does this dynamic entrainment of low frequency phase have an effect upon local computation and long-range communication? First, LFP phase modulates the instantaneous spike probability and can shift spike timing [34, 62–66]. Therefore, low-frequency phase entrainment will shift the relative timing of spiking and synaptic activity. This may have important consequences for cognitive processing, since the strength of theta frequency phase-locking of neuronal spikes is correlated with memory performance [67]. Second, coherent low-frequency oscillations appear to be important in regulating large-scale networks [68, 69], such that phase entrainment in one area may have effects that propagate throughout a larger network due to inter-regional phase locking. These patterns of phase coupling between multiple brain areas can impact the spiking of single cells and may help bind together anatomically-dispersed functional cell assemblies [70]. Therefore, dynamic entrainment of low frequency phase is positioned to have a broad impact on processing at multiple spatial and temporal scales, from the spike timing of single neurons to the integrated action of inter-regional functional brain networks.
