Table 1.

Mean (± standard error of the mean) (a) body weights (kg) across the pre- and post-weanling period, (b) unconditioned response percentage (UR %) at sessions 1 (S1) and 4–5 (S4–5), and (c) conditioned response (CR) onset and peak latencies from the last session of acquisition (session 5 for subjects PD 17 or 24 at the start of training; session 4 for subjects PD 61 at the start of training). Data are presented as a function of age at initial eyeblink training (PD 17: n = 8; PD24: n = 8; PD 61: n = 5).

	Body Weight (kg)				UR percentage and CR latency
Age	PD 14–15	PD 22–23	PD 36	PD 43	UR% (S1)	UR% (S4–5)	CR Onset	CR Peak
PD 17	0.2 ± 0.02	0.3 ± 0.02	0.9 ± 0.03	1.1 ± 0.03	53 ± 13	83 ± 9	191 ± 16	280 ± 14
PD 24	0.2 ± 0.03	0.3 ± 0.03	0.8 ± 0.06	1.1 ± 0.06	61 ± 12	85 ± 4	182 ± 19	274 ± 15
PD 61	0.2 ± 0.03	0.3 ± 0.03	0.9 ± 0.06	1.2 ± 0.07	85 ± 4	90 ± 4	171 ± 15	290 ± 21