FIGURE 2.

Loss of circadian timing did not affect basic excitatory circuit properties in the hippocampus. Recordings from the perforant path of the dentate gyrus of input/output curves (I/O, a1), paired pulse ratio (PPR, a2) and long‐term potentiation (LTP, a3), with the same measures in the Schaffer collateral CA1 path of hippocampus (b1‐3; n = 24 ENT, n = 23 ARR animals). There were no significant differences in these three measures between ENT (red) and ARR (green) either in dentate or CA1 (2‐way ANOVA with repeated measures for stimulus, ISI, and time, p > .05). Inserts show representative traces at different stimulus intensities. Note that PPR and LTP responses are evaluated by their slopes, not amplitudes. Dotted lines in LTP panels indicate baseline values extrapolated past tetanus (arrow). All scale bars are 0.5 mV, 10 ms. Data expressed as means ± SE; for clarity, PPR only shown up to 250 ms, LTP error bars shown every 600 s