The sharp wave/ripple (SWR) onset times of different cells is opposite to their order before SWRs

<p><b>Copyright information:</b></p><p>Taken from "Place-selective firing contributes to the reverse-order reactivation of CA1 pyramidal cells during sharp waves in open-field exploration"</p><p></p><p>The European Journal of Neuroscience 2007;26(3):704-716.</p><p>Published online Jan 2007</p><p>PMCID:PMC2121123.</p><p>The Authors (2007). Journal Compilation Federation of European Neuroscience Societies and Blackwell Publishing Ltd</p> (A)Representative example illustrating the spike-time regression procedure. Traces at the top show wide-band (1 Hz−5 kHz) recorded channels from three different CA1 sites (three different tetrodes) and the band-pass filtered (150–250 Hz) trace of the third channel, in which the SWR event is clearly present. A 200 ms SWR window was centred at the SWR peak time and is marked by the horizontal line above the top trace. The first and last spike-times are marked by bold raster lines on the raster plot and arrows mark their spike-time intervals. The time axis on the bottom illustrates spike-times relative to the leading border of the SWR. (B)Regression analyses of the times of last spikes before and first spikes during exploration-associated (e)SWRs all produced negative correlations for different sessions, but not during immobility-associated (i)SWRs or SWR that occurred at least 15 s outside of exploratory periods (iSWR-15 s). The frequency histograms of regression coefficients measured in different recording sessions are shown. Grey bars show those recording sessions with significant ( 0.05) regressions, with the remaining sessions indicated in white. Spike-times of different cells measured during different SWRs were analysed together. Negative spike-times before SWR onset are relative to the leading SWR border for eSWRs (as shown in A) or relative to the end-time of the previous exploration sessions for iSWRs. (C)Average (± SEM) of correlation coefficients of last pre-SWR and first SWR spike-times. (eSWR: = 26; iSWR: = 26; iSWR-15 s: = 24 sessions)