Figure 4.

Impaired long-term memory in CBP cKO mice. A, Percentage of time spent freezing for CBP cKO and control mice. The animals received one single footshock at 1 mA intensity for 1 s during the training session. There is no significant difference in the percentage of time freezing between the two genotypic groups (p > 0.1). The mice were returned to the conditioning chamber 24 h after the footshock. CBP cKO mice showed significantly less time freezing than the control during the testing session. *p < 0.05. B, Percentage of time spent freezing for CBP cKO and control mice. There is no significant difference in percentage of time freezing between the two genotypic groups during the training session (p > 0.1). CBP cKO mice displayed significantly less time freezing than the control during the testing session. ****p < 0.0001. C, PI for CBP cKO and control mice at a 24 h retention delay using a novel-object-recognition task. The animals spent equal amounts of time exploring objects during the sample phase. However, CBP cKO mice spent significantly less time inspecting the novel objects than the control did during the choice phase at 24 h posttraining. ****p < 0.001. PI = (time spent on novel object/total inspection time for objects) × 100. NS, Not significant.