MacMahon, Stephen William2021-10-212021-10-211979https://hdl.handle.net/10092/102757http://dx.doi.org/10.26021/11891The objective of the experiments in this study was to investigate the proposed aversive stimulus properties of scopolamine hydrobromide (1.2 mg/kg I.P.) All research designs were based on the respondent condit ioning paradigm. In Experiment I, scopolamine was used as a (putative) aversive UCS in order to produce condit ioned suppression of licking to a light CS. No evidence of suppression was found.It was proposed that this may have been due to the inability of the UCS itself to suppress responding. In a second experiment, scopolamine injections were paired with one side of a shuttlebox, and saline injections were paired with the other side. Subsequent free choice tests yielded a constant prefer- ence for the saline associated side. In a further test where subjects were injected 20 minutes prior to confine ment, no avoidance of the scopolamine associated side was observed.These results suggest that the onset of scopolamine effect is aversive.enAll Rights ReservedAversive stimuliScopolamineThe aversive stimulus properties of scopolamineTheses / Dissertations