Attenuation of "acute" habituation by scopolamine in the black-tailed prairie dog (Cynomys ludovicianus).

The hypothesis after scopolamine attenuates habituation occurring within a training session as well as that occurring between training sessions was tested and confirmed. Scopolamine injections (.5 mg/kg) reduced spontaneous wheel running in the prairie dog. The same dosage did not affect the threshold for wheen running induced by electrical brain stimulation (EBS). Another experiment demonstrated that EBS-induced running declined during a 10-min. stimulation period and indicated that the decline was habituative since the response was repeatedly dishabituated. In a final experiment .5 mg/kg of scopolamine reduced habituation of EBS-induced wheel running during 10-min. sessions.