Fig. 3.

Resting potential differed between firing pattern categories and became more negative with age. A: transient spikers. B: sustained spikers, divided into sustained-A (open circles) and sustained-B (filled circles). Most data (circles) are from rat at room temperature; some are from rat at warmer temperatures (inverted triangles), or mouse at room temperature (stars and crosses). After P7, sustained-A and sustained-B spikers diverged, such that sustained-B values were more negative than sustained-A values. Lines in A and B: linear regression fits (y = mx + b) to rat data at 22–25°C. Transient neurons (68): m = 0.7 ± 0.13 mV/d, b = −58.9 ± 0.96 mV, r² = 0.32. Sustained neurons (45); m = 0.7 ± 0.17 mV/day, b = −49.9 ± 1.20 mV, r² = 0.28.