Effects of LSD-25 on avoidance behavior and locomotor activity in mice.

C57BL/6(C57) mice were tested in a shuttle box under the influence of LSD-25 in two sets of experiments. In the first set, the pretrial administrations of LSD (0.05, 0.1, and 0.2 mg/kg) were followed by dose-related performance improvements. In the second set, the posttrial administration of LSD (0.2 mg/kg) immediately after each experimental session improved the performances of the mice. No effect was evident when the hallucinogen was injected 2 h after training, thus showing that LSD improved the memory processes of the C57 mice in these experimental conditions. Dose-related activity depressant effects were evident in a third set of experiments, carried out in a toggle-floor box.