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Over thirty years have passed since psychologists became seriously interested in the proposition that laboratory rats might emit distinctive odors upon experiencing the particular goal events of food reward and nonreward, treatments ubiquitously employed in behavioral experiments. The articles in Section 1 below draw heavily on findings, inferences, techniques, and research designs developed early in this period. Therefore, those matters are discussed here, in some detail, as a general introduction to much of what follows. The dependent variable of interest was patterning in speed of response in a runway to reward and nonreward, and the critical independent variables involved trial sequences among subjects.