Conditioning insulin effects

It has previously been demonstrated that after a number of insulin injections in rats, an injection of a placebo leads to an elevation in blood sugar. It has been suggested that this apparent conditioned compensatory response is an artifact resulting from stressing the subject (when large doses of insulin are used) or represents a nonassociative phenomenon (when small doses of insulin are used). These two suggestions were rejected on the basis of the results of Experiments 1 and 2, respectively. Experiments 3 and 4 demonstrated that although the behavioral effects of insulin can be conditioned to the injection procedure, such conditioned insulinlike behaviors (contrary to suggestions of many investigators) are not mediated by a pypoglycemic state.