The purpose of this experiment was to explore psychological mechanisms underlying the phenomenon of extremization of judgments (accentuation) under stress. Specifically the question was raised whether accentuation was due to some change of the internal representation of the objective scale (the personal reference scale, Upshaw, 1969). In the case of no indication for such a change a further analysis of accentuation concerning the nature of response shifts was intended.
Four different degrees of stress were induced by varying levels of white noise stimulation. Induction of stress was monitored by measures of electrodermal and cardiac activity. Ss in each of the stress conditions rated statements on social issues for degree of socialist or communist attitude expressed. In part I of the experiment Ss were free to choose any bipolar scale comprising 2–13 categories. In part II they repeated their judgments on a 9-point bipolar scale.
As degree of stress was not systematically related to scale selection in part I, there was no support for the hypothesis of a change of personal reference scale. A linear function between a general instability of the judgmental frame of reference and stress was found, however. Again an increasing tendency to accentuate under intermediate stress levels was observed. Under medium degree of stress an increased tendency to vary scales was also observed.