The dynamics of hippocampal ripple generation was explored through recordings with NeuroNexus acute 32-channel probes (A1x32-15mm-100-177-A32) in awake mice. The 3.1 mm span of recording sites on the linear probe with 100 µm site spacing enabled current source density (CSD) analysis across some of cortex, through dentate gyrus (DG) and CA1, and into thalamus. Results published in eLife from Koichiro Kajikawa et al. and the Thanos Siapas group at Caltech describe hyperpolarization in CA3 together with depolarization in DG and CA1 leading up to ripple-frequency LFPs.