Figure 7.

Reactions to rotated novel arena (aligned). The mean correlation of all place fields recorded simultaneously for each rat was calculated between the trials New1 and New2RA. Rats whose place fields did rotate with the arena have a high correlation (∼0.25 or above). Rats whose place fields did not rotate with the arena have a low correlation (∼0 or below). The spatial representations of young rats had high rotated correlations on every occasion. The spatial representations of aged memory-impaired rats had low correlations in the initial session but, in the second or third session, the correlations were as high as in young rats. In sessions there after, the place fields of the aged rats had low correlations on some occasions and high correlations on other occasions.