Age-induced cognitive alterations in OF1 mice.

Female OF1 mice aged 17-18 months were compared with female OF1 mice aged 7-11 weeks for locomotor activity, pain sensitivity, and cognitive performance using the Morris water maze, passive and active avoidance, and the elevated plus-maze learning protocol. Performance of old mice was impaired compared to those of young mice for both locomotor activity, pain sensitivity, and the four cognitive tests including the elevated plus-maze not previously used in studies on aging. Using complementary experiments and a detailed analysis of the results, we have shown that the reduction of learning and memory do not result from a decline of sensory and motor capacities. We conclude that female OF1 mice aged 17-18 months show true cognitive deficits.