Fig. 6.

Incentive runway training and retention tests. Completion speed (cm/s) in young and old rats during the pre-exposure (sessions 1–7), learning (session 8–11), and overtraining (session 12–14) phases of training (A); and during the 5 trials of the retention session conducted 15 days after training (B). Net running speed after subtraction of time spent in distractions for the initial acquisition (sessions 8–14) (C) and the 5 sessions of the retention phase (D). Incidence of sprints (uninterrupted runs without any pause) of young and old rats in session 8–11 (E), and time spent in distractions (latency to start and pauses) (F). Data are mean ± standard error of the mean (SEM) (n = 7–8). * p < 0.05; ** p < 0.01 versus young.