Fig. 5: Anatomically identified MS cells show differential coupling to CA1 tSCs.

a Main projection targets of Teevra, Orchid and low rhythmic (LRN) MS neurons (MS, medial septum; DG, dentate gyrus; PrS, presubiculum; EC, entorhinal cortex)^{47, 48, 64}. b Top, schematic of the juxtacellular labeling and recording experiment with concurrent recordings from CA1 pyramidal layer in awake mice. Bottom, example of simultaneously recorded CA1 LFPs and MS spikes. c Left, tSC-coupling, immunoreactivity and projection targets of identified MS neurons. Cells were sorted based on the fastest tSC they were coupled to. Right, number of Teevra, Orchid and LRN neurons phase-coupled to each tSC. PV, parvalbumin; CB, calbindin; mGluR1a, metabotropic glutamate receptor 1a; NK1R, neurokinin 1 receptor; SUB, dorsal subiculum; PrSd, dorsal presubiculum; RSg, granular retrosplenial cortex. AJ50j is a putative EC-projecting neuron, as its main axon faded just rostral to caudo-dorsal EC. d Top, Z-scored phase histograms of all identified tSC-coupled MS neurons, sorted into four groups based on the tSC they are coupled to (blue, low firing rate; yellow, high firing rate). Zero phase corresponds to tSC troughs (white vertical lines). Cells within each group were sorted by their preferred phase in two blocks: top, cells with maximum firing rate before the most negative tSC trough; bottom, cells with maximal firing after the most negative tSC trough. Bottom, polar plot showing the phase preference (angle) and coupling strength (radius) of different MS neuron types for each tSC. e Distribution of time lags across different MS neuron types that realize the maximal phase locking as quantified by Rayleigh’s Z-values, separately for each tSC. Source data are provided as a Source Data file.