Fig. 6.

PA learning. a Latency to enter the dark on training day 1. b Latency to enter the dark on test day 2. c Latency to enter the dark on test day 3. No differences in performance between transgenic and wild-type mice were found in either genetic background on day 1. In addition, no significant difference between genetic backgrounds, irrespective of genotype, was identified for day 1 latencies. B6D2F1 transgenic mice exhibited lower latencies to enter the dark than B6D2F1 wild-type mice on day 2, but by day 3 they showed improved learning. In (b), “a” represents a decreased latency to enter the dark in transgenic mice compared to wild types. In (c) **Represents the overall increase in latency in B6D2F1 transgenics compared to B6 transgenic mice. All P values ≤0.001 by three-way ANOVA and simple-effects analysis