Locomotion was recorded for 30 min in open-topped, square arenas with grey walls (25 cm × 25 cm × 30 cm), under dimmed room light conditions. The session length was based on other studies employing the hyperactivity model [3,30]. Data were collected in 1-min bins using Ethovision (Noldus, The Netherlands), and expressed as distance traveled (in cm) during 30 min. One week before drug testing, mice were exposed to the open field test in order to familiarize the animals to the testing procedure and to compose treatment groups with equal mean baseline activity.