The differentiation of individual-specific, stimulus-specific, and motivation-specific response patterns in activation processes: an inquiry investigating their stability and possible importance in psychophysiology

The role of specific response patterns obtained by means of psychophysiological activation and their temporal stability are meeting with an increasing interest in the literature because of a low correlation between psychophysiological variables and of possible implications with regard to pathogenetic mechanisms in psychosomatic disease. Two empirical studies are presented that were conducted under similar stress conditions (mental arithmetic, free speech, cold-pressor test, blood-taking) and have been monitoring similar activation variables (seven physiological and four or five psychological variables) - one of which using a large sample of 125 students, the other one consisting of 47 students, who were tested three times week- by-week. Findings reveal that substantial proportions of variance in the three-factorial ANOVA (subjects, situations, variables) may be considered on the basis of individual-specific (23-29% for physiological variables, 6-11% for psychological variables), stimulus-specific (5-19% for physiological variables, 1-11% for psychological variables), and motivation-specific (21% for physiological variables, 10% for psychological variables) response patterns. Five evaluation procedures on nominal, ordinal, and interval data levels as well as various definitions of similarity found in the reaction patterns are used in a comprehensive approach to the analysis of specificities. Estimation of variance components, global tests, and individual tests are applied. The results prove to be reliable and rather stable, at least over a period of several weeks. In total, about one fourth of the subjects show a stable individual-specific response pattern on physiological variables. The results are discussed with respect to data and sampling problems as well as to various methods of data analysis.