Figure 7

Spatial working memory performance in the 8-arm radial maze for R26CT and R26CT-CRE mice. A) Schematic diagram of the training phase procedure (8 arms open, 8 arms baited). B) At 3 months of age: R26CT (black bars, n = 11), R26CT-CRE (white bars, n = 12). C) At 8 months of age: R26CT (black bars, n = 11), R26CT-CRE (white bars, n = 12). No significant differences were found between R26CT and R26CT-CRE mice at either 3 or 8 months of age in the training phase (B, C). Performance of both mice improved with experience. D) Schematic diagram of the delayed spatial win-shift assay (RI = retention interval). E) At 3 months of age: R26CT (black bars, n = 11), R26CT-CRE (white bars, n = 12). Both R26CT and R26CT-CRE mice improved with experience and there was no significant difference between genotypes at either days 11–13 or 18–20. F) At 8 months of age: R26CT (black bars, n = 11), R26CT-CRE (white bars, n = 12). R26CT mice improve with experience while R26CT-CRE mice do not. Furthermore, there is a significant difference between R26CT and R26CT-CRE mice during the late time block (days 18–20) indicating that the spatial working memory of R26CT-CRE mice is impaired. Bars represent the mean total error ± SEM of the first 3 days and the last 3 days of either the training or test phase performance. Significance between performance blocks and between genotypes was determined using a mixed ANOVA analysis (*p < 0.05, ** p < 0.01).