Evidence for slow (2–) and gamma frequency coherence between spike trains and local field potentials in the cerebellum

Abstract A method for detecting relationships between single-unit spike trains and local field potentials (LFPs) was developed and applied to recordings from rat cerebellum. LFPs were repeatedly filtered with a shifting frequency window. The resulting traces were transformed into peak-time point processes for comparison with spike trains using “relative-phase” analysis (Biol. Cybernet., in press). Discharge of some Purkinje cells was phase-related to LFP oscillations in the 2– 10 Hz and 30– 50 Hz frequency ranges. This analysis method revealed hidden coherency between spike-trains and LFPs. The findings suggest that cerebellar activity is, to some extent, temporally organized according to both slow and fast rhythms.