Research Paper Volume 15, Issue 13 pp 5990—6010

Figure 4. Long-term retention of everyday spatial memory in aging. (A) Rats received a strong encoding (3 rewards, filled circle) trial and 30 min later different memory-modulating events. The novel box was represented in green, the encoding zone was represented in blue, and the second strong encoding trial was represented in orange. Twenty-four hours after encoding, they were tested in a probe trial with 5 non-rewarded sandwells (open circles). (B) After strong encoding, the percentage of correct digging was not different from chance (dashed line) in both groups (No prior training: one-sample t-test, t₁₂ = 1.58, p = 0.14; Priorly trained: t₁₂ = 0.87, p = 0.40). No difference was observed between the two groups (unpaired t-test, t₂₄ = 0.43, p = 0.67) (C) Novel box exposure after encoding did not lead to above-chance performance in both groups (No prior training: one-sample t-test, t₁₂ = 1.59, p = 0.14; Priorly trained, t₁₂ = 0.05, p = 0.96). No difference was observed between the two groups (unpaired t-test, t₂₄ = 0.73, p = 0.48). (D) Exploration in the encoded zone after encoding increased the percentage of correct digging in priorly trained group only (No prior training: one-sample t-test vs. chance, t₁₂ = 0.47, p = 0.65; Priorly trained: one-sample t-test vs. chance, t₁₂ = 2.76, p = 0.017). A significant difference was observed between groups (unpaired t-test, t₂₄ = 2.37, p = 0.03). (E) With a second strong encoding trial, the percentage of correct digging was significantly above chance in both groups (No prior training: one-sample t-test, t₁₂ = 3.31, p = 0.006; Priorly trained: t₁₂ = 2.74, p = 0.02). No significant group difference was observed (unpaired t-test, t₂₄ = 0.65, p = 0.52) Data are presented as mean ± SD. ^*p < 0.05, ^**p < 0.01.