Figure 5.

Percentage of place cells, low-rate cells (<0.1 Hz), and other cells; histograms of rate change score. A, Place cell percentage. The seizure group (red) shows a short-term drop in postseizure session 3 of each day followed by a partial rebound in session 4; a long-term decline is seen in preseizure sessions 1 and 2 across days 1, 4, and 8. The control group (blue) shows no short- or long-term effect; its percentage stays around 60% across sessions and days. B, Low-rate cell percentage. The fraction of low-rate cells for the seizure group is complementary to the fraction of place cells within and across days. In each day, there is a short-term increase in session 3 and a partial reversal during session 4. There is also a long-term increase seen by comparing preseizure sessions across days. The control group shows no short- or long-term effect; its percentage stays around 25–30% range across sessions and days. C, Other cell percentage. Pyramidal cells that do not qualify as place cells or low-rate cells are classified as “other” cells (see Materials and Methods). The fraction of the other cells fluctuates within the range of 5–20%, but there is no obvious short- or long-term trend for either group. D, Histograms of rate change score comparing discharge rate in session 3 to discharge rate in session 1. The most striking feature for all 3 d is the large percentage of cells from seizure rats whose rate change score falls into the −1 category, indicating that the spike activity of the cell underwent a great decline. In addition to this within-day effect, the cell percentage in the −1 category increases from day 1 to day 8. Error bars indicate SEM.