Figure 5
Response competition between sucrose dish approach and lever pressing. A. Averaged time-course of approach responses to sucrose dish just before, during and after first CS+ cue presentation. B. Same information for pressing on sucrose-associated lever. Each panel compares cue-triggered responding after microinjections of vehicle (white circles), CRF 500 Ī¼g (green circles), CRF 250 Ī¼g (blue circles), or amphetamine 20 Ī¼g (red circles). Both CRF and amphetamine reduced the peak of cue-triggered approaches to the sucrose dish, but simultaneously increased cue-triggered lever pressing. It is impossible to perform both actions at exactly the same time, and so conditioned dish approaches may have been suppressed as a result of response competition from increased lever pressing that occurred during the same 30-sec period.