Trait anxiety and autonomic indicators of the processing of threatening information: a cued S1-S2 paradigm

The aim of this study was to use autonomic parameters in a cued S1-S2 task to examine associations between the processing of threatening information and trait anxiety in normal individuals. Forty-six student volunteers were designated high- or low-anxious due to pre-defined cutoff scores on the STAI. A cued S1-S2 task was presented in which the type of warning signal (S1) was consistently related to either threatening or non-threatening pictures (S2). Ten threat and 10 non-threat pictures were randomly presented. Heart rate and electrodermal activity were recorded in the time interval between S1 and S2. Results indicated deeper heart rate decelerations on threatening trials in high-anxious as compared to low-anxious individuals. For non-threatening trials, the opposite pattern was found. Moreover, high-anxious participants exhibited higher electrodermal responses to the S1, irrespective of the trial's valence as well as stronger responses to the threatening S2. Autonomic responses can, thus, be regarded as sensitive markers of information processing differences in trait anxiety.