Fig. 4

Performance in the open-field task. A Open-field task. Habituation to the apparatus and saline injection was performed for 30 min per day for 3 days prior to the start of the experiment. The apparatus was a custom-made white vinyl chloride box measuring 50 cm length × 50 cm width × 50 cm height. Cameras (Logicool HD Webcam C270n, Logicool) were placed overhead, 106 cm from the bottom of the box. Videos were recorded on Windows PC. During habituation, the animals were placed in the open-field box immediately after receiving the intraperitoneal injection of saline and allowed to behave freely. The order of the saline and mecamylamine 2 mg/kg and 5 mg/kg injection was randomized. The duration of the experiment was set at 90 min. A white noise (75 dB) was presented throughout the experiment to mask external noise. B Time course of open-field activities after the injection of saline or mecamylamine (N = 12). C Overall locomotor activities from 10 to 60 minutes from the start of the open-field task (N = 12; *p < 0.05). D Amount of feces collected after 90 minutes of open-field task (N = 12; **p < 0.01). E Amount of urine collected after 90 minutes of open-field task (N = 12). “MEC” indicates mecamylamine. Error bars indicate standard error of the mean