Figure 3.
(A) Representative gamma burst in a head-fixed P2 rat during sleep. Traces from top: CA1 multiunit activity (MUA; filter: 500-5000 Hz); local field potentials (LFP) recorded from CA1 and stratum radiatum (filter: >100 Hz). Note the phase reversal across the two hippocampal layers and the concurrent increase in multiunit activity. (B) Depth profile during a gamma burst (shaded region) for the same P2 subject. Note that the highest amplitude is recorded in the middle portion of the stratum radiatum. Each recording site has a vertical separation of 100 μm. (C) Depth profile of a startle-related SPW (left) and a neocortical “spindle” (right) from another P2 rat during sleep. For the SPW, note the phase reversal between CA1 and stratum radiatum (asterisk). For the spindle, note the absence of phase reversals and the diminishing amplitude as the wave travels from neocortex toward hippocampus.