Aged rats are impaired in the Morris swim task. Analysis of path lengths (a) shows that when the platform was hidden, adult rats (black circle) swam shorter paths to reach the hidden platform than did the aged rats (black square), and this difference was significant on day 4 of training. During trials in which the platform was visible, adult rats (open circle) and aged rats (open square) had comparable path lengths. During the probe trial (b), adult rats (white) spent significantly more time than aged rats (grey) in the quadrant that previously held the platform (target), but not the opposite quadrant (all data are mean ± SEM; *p < 0.05; **p < 0.01, adult vs. aged animals).
Gheidi et al. BMC Neuroscience 2013 14:100 doi:10.1186/1471-2202-14-100