The frequency of the responses, i.e., squares entered (ambulation), rearing and grooming, were recorded over 30 min for saline, and 0.25, 1.0, 2.0 and 4.0 mg/kg scopolamine treated groups. Scopolamine produced an inverted U dose-response curve for ambulation, an increase in rearing but no effect on grooming. All three responses decreased over time; scopolamine did not attenuate this rate of habituation. There did appear a dose-related time effect. It was concluded that scopolamine may have different effects on various responses recorded simultaneously over a range of doses. The results when compared to other experiments emphasized the importance of environmental factors in determining drug effects on behaviour.
