Effects of ageing on locomotor and exploratory activities. A–D) Aged (96–99 weeks old) mice showed decreased locomotor activity compared with young adult (8–12 weeks old) mice (comparisons, traveled distance, unpaired two-tailed t-test, p=0.001; center/periphery, unpaired two-tailed t-test, p=0.06; average speed, unpaired two-tailed t-test, p=0.0001; fraction of time moving, unpaired two-tailed t-test, p=0.01). E–F) The same aged animals showed less head dips (unpaired two-tailed t-test, p=0.02), however the total duration of the head dips did not change significantly (unpaired two-tailed t-test, p=0.4) (* indicate statistically significant differences p<0.05, n=6 aged, n=6 young adult mice; same animals as on Fig 5).