Conditioned Motor Activity and Place-Preference Responses as a Function of d-Amphetamine Dose Level

Spontaneous motor activity (SMA) responses to stimuli predicting d-amphetamine injection were investigated in a Pavlovian conditioning paradigm. Three groups (saline, 1.0mg/kg and 4.0mg/kg doses) of rats underwent a 12-day period during which Injection-Conditioning and Non-Injection Conditioning treatments were alternated. This sequence was then followed by two Test/Extinction Days on which all three groups received saline injections. Subjects in the 4.0mg/kg, but not the 1.0mg/kg group were more active during the 30 minute pre-injection period on the second Conditioning Day than were Saline Group subjects. Test Day post-injection SMA levels of the two Drugged Groups were not significantly different, but the activity of the combined Drug Groups was significantly higher than that of the Saline Group. These results are consistent with previous research and in addition are the first report of an amphetamine-produced conditioned SNA increase to pre-injection conditioned stimuli.