Figure 7.

Comparison of the hippocampal theta activity between correct lever press responses for RFTs (RFT) and incorrect lever press responses for non-RFTs [non-RFT(error)] on the late learning stage of the FN task. The 0-ms period indicates the onset of stimulus presentation. The period was divided into 45 sub-periods of 100 ms each. The mean hippocampal theta power from 500 to 400 ms before the stimulus onset was counted as the −400-ms period (no stimuli were present and no rats pressed the lever during this period), and the relative theta power calculated for each period was normalized to that of the −400-ms period (relative theta power of each period = theta power of each period/theta power at the −400-ms period). The hippocampal theta power increased in 400- to 1100-ms epochs and decreased at 1900–4000 ms periods during the correct lever press responses for RFTs compared with during incorrect lever press responses for non-RFTs in the late learning stage of the FN task (all p < 0.05). Error bars indicate s.e.m.