Figure 9.

Object recognition (A–C) and spatial abilities (D–F) of GCLM −/− mice. A, During the first familiarization to 3 objects, GCLM −/− mice (n = 12) explore them more than +/+ mice do (n = 14) (*p = 0.012). B, Both genotypes show preference for the displaced object A (^&p < 0.001), but GCLM −/− mice investigate more one of the nondisplaced object (object C) than +/+ mice do (*p = 0.002). C, Novel object recognition is impaired in GCLM −/− mice (p = 0.008). When one of the nondisplaced object (object C) is replaced by a novel object, GCLM −/− mice explore this novel object and the previously displaced object A with equal intensity. Exploration of the previously displaced object A remains higher in GCLM −/− than in +/+ mice (* p = 0.01). Only the familiar, nondisplaced object (object B) is less investigated than the novel object by GCLM −/− mice (^&p = 0.004). In contrast, +/+ mice explore more the novel object than the two familiar objects (^&p < 0.001). D, Spatial working memory in a rewarded alternation task is intact in GCLM −/− mice. Percent of correct choice increases over the trial sessions similarly in GCLM −/− (n = 8) and GCLM +/+ (n = 8) mice. E, Spatial reference learning in a water maze is intact in GCLM −/− mice. The ability to find a hidden platform (goal) improves equally well in GCLM −/− (n = 6) and +/+ (n = 11). After the platform was moved to another location (at the time indicated by an arrow), both genotypes learn equally well the new platform position. F, Spatial reference memory is intact in GCLM −/− mice. During the probe trial (PT), both genotypes spend more time in the goal quadrant than in the other quadrants (*p ≤ 0.003). All data are presented with the mean ± SEM.