Complete the triangulation: Quantifying differential fear conditioning with a noninterfering and sensitive behavioral measure along with self-report and physiological measures.

According to the multicomponent view, emotion is expressed through subjective feelings and thoughts, physiological activation, and behavioral responses. In human fear conditioning research, the former two are much more popular than the third category. One concern is that concurrent behavioral probes may interfere with the conditioning process. To allow triangulation of emotion research through simultaneous employment of subjective, physiological, and behavioral measurement, it is necessary to find behavioral measures that meet the criteria of causing no interference while being sensitive to conditioning. In this study, a basic visual attention task was examined in terms of its impact on differential fear conditioning as measured by both subjective (i.e., self-reported fear and shock estimation) and physiological (i.e., skin conductance response/SCR) expression; and its ability to detect fear conditioning indicated by a reaction time (RT) or accuracy difference between the two conditioned stimuli (CS+ vs. CS-). While participants in the probe group (n = 86) completed differential fear conditioning with the behavioral task, those in the no-probe group (n = 76) underwent conditioning by itself. Based on self-reported fear, shock estimation, and SCR, both groups successfully acquired differential fear with no apparent between-group difference in the degree of conditioning. In the probe group, RT but not accuracy exhibited a difference between CS+ and CS-. These findings suggest that the selected visual attention task does not interfere with differential fear conditioning measured via SCR and self-report and is a sensitive measure of differential conditioning. Exploratory individual analyses also revealed significant relationships between the above measures.