The representative locomotor patterns are shown for mice treated with saline (a) or GBR 12909 (b). a) Mice treated with saline display very limited activity, making only one or two excursions around the chamber with limited exploration into the center of the chamber. b) Mice treated with GBR 12909 display far greater levels of activity, with numerous areas of focused activity and greater variety of paths taken. Data are also presented for locomotor activity (transitions), pattern (spatial d), and exploratory behavior (holepokes) with mice treated with GBR 12909 displaying hyperactivity, increased exploratory behavior, and straighter line movements (lower spatial d) than mice treated with saline.