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Recent studies of classical defense conditioning at the Iowa laboratory have been concerned largely with the relation of drive level (D) to level of performance in conditioning. According to the theoretical formulation offered of the results of these studies, the associative factor, H, and drive factor, D, combine multiplicatively to determine reaction potential, E, which in turn determines the strength of the response, i.e., R = f (E) = f(H) X f(D). It has further been assumed that D is a function of (a) the intensity of the UCS, and (b) the score on the Manifest Anxiety (A) scale (8). The mechanism underlying these assumptions presumably involves the emotional response (re) to the noxious stimulation of the UCS. This emotional response is assumed to be relatively persistent, extending well beyond the intertrial intervals usually employed in conditioning experiments. Thus D, present at the moment of a conditioned an- ticipatory response, is conceived to be, in part, a function of the residual effects of the emotional reaction to the noxious stimulation of preceding trials. The higher the intensity of the UCS, the greater the magnitude of re and the higher the level of D. The use of the A scale to define D has assumed that the differences in A scores reflect differences in the magnitude or strength of the emotional response to the same UCS by these Ss. That is, Ss who make high A scores give a greater emotional response (re) than Ss who make low A scores. Since it has been assumed that D is a function of the magnitude of re, these high A Ss should exhibit a higher level of response than low A Ss. The evidence confirming this prediction has recently been summarized by Spence and Ross (6).

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Proceedings of the Iowa Academy of Science





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©1958 Iowa Academy of Science, Inc.



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