Firing response of hippocampal CA1 principal cells during sharp-wave/ripple events in sleep. Top trace, wide-band (1H–5 kHz) local field potential recorded in the pyramidal cell layer. Bottom trace, 140–250 Hz band pass-filtered local field potential highlighting ripple frequency events. Raster plots, spike times of simultaneously recorded CA1 principal cells (one cell per row). Note the firing synchrony during ripple events.
The objective of our programme is to define how coordination of neuronal activity in the hippocampus and connected subcortical circuits contributes to memory processes during active waking behaviour and sleep.