Skip to main content
. 2003 Sep 5;100(19):11047–11052. doi: 10.1073/pnas.1934854100

Fig. 1.

Fig. 1.

Coexistence of field gamma-frequency oscillations and high-frequency oscillations in hippocampal area CA1. (a) Gamma oscillations generated in a CA1 slice by 1 μM kainate. Field oscillations are seen in both stratum oriens (s. oriens) and stratum radiatum (s. rad.). High-pass filtering of the field recording (>100 Hz) reveals discrete epochs of high-frequency activity phase-locked to the ongoing gamma oscillation in stratum oriens but not stratum radiatum. Spectrograms of the high-pass-filtered data reveal bursts of activity within a broad frequency range modulated at gamma frequencies in stratum oriens only. (b) Stratum oriens and stratum radiatum recordings in the presence of 1 μM kainate in slices where stratum oriens and alveus are separated from stratum pyramidale and stratum radiatum. Kainate generated a near-continuous train of high-frequency activity in stratum oriens but no activity in stratum radiatum. Spectrograms of the high-pass-filtered data show a more narrow distribution of frequencies with no modulation at gamma frequencies. No activity was seen in stratum radiatum. (Scale bars, 0.2 mV and 100 ms.)