The relationship between the Anxiety Sensitivity Index and two common measures of heartbeat perception

Jeffry Benton Snell

Abstract

Previous research has produced inconsistent indications of the relationship between self-reported anxiety and visceral perception. Those inconsistencies may have resulted from the use of differing tasks, or may represent a parallel relationship of subject belief systems and physiological state rather than accurate interoception. In this experiment, 163 subjects were administered anxiety inventories: The Anxiety Sensitivity Index (ASI), the Body Sensations Questionnaire, and the State-Trait Anxiety Inventory. Of this original group, 60 subjects (30 female and 30 male) were selected based upon their ASI scores and grouped into High Anxiety ( n = 30) and Low Anxiety ( n = 30) gender-balanced groups using procedures previously described by Sturges and Goetsch (1996). Subjects were administered the Schandry heartbeat counting task (1981) and the Method of Constant Stimuli procedure developed by Brener, Liu, and Ring (1993). The primary hypothesis was that the Schandry task would show a significantly stronger positive correlation with ASI score due to the presumed commonality of expectations operating in both measures. Both correlations were within the range of values expected by chance, however, and the planned examination of the difference between the strength of these relationships was considered statistically unjustified. Comparable weak relationships were observed between the two measures of cardiac perception and BSQ and STAI. Statistically significant positive relationships were found between self-report measures of anxiety. An analysis of the number of subjects classified as "aware" on Schandry indicated that 21 subjects (7 Low ASI subgroup and 14 High ASI subgroup) (35%), were thus classified as "high aware". On MCS, 12 subjects (7 Low ASI and 5 High ASI) (20%) were classified as showing high awareness. Analysis of gender revealed significant differences by gender on both visceral perception tasks. These results are consistent with the large body of studies that have shown no relationship between anxiety sensitivity and visceral perception tasks such as MCS or Whitehead, but is inconsistent with a number of studies which have reported strong relationships between anxiety sensitivity and Schandry task performance. In addition, significant strong gender differences were observed on both visceral perception tasks, although some investigators have reported no effects of gender on the MCS task.