Examining the Quadratic Association Between Self-Reported Interoceptive Accuracy and Attention

Murphy et al. (2019) proposed a 2 x 2 factorial framework to categorize individual differences in interoception: Factor 1, differentiates what is measured (interoceptive accuracy, the ability to accurately perceive interoceptive signals vs. interoceptive attention, the degree to which interoceptive signals are the object of attention); Factor 2, distinguishes how interoception is measured (via self-report measures assessing an individual’s beliefs regarding their interoceptive ability vs. objective measures, that assess performance on objective tests of interoception). Subsequently, Murphy et al. (2020) provided further evidence for this framework, finding that self-report measures of interoceptive accuracy such as the Interoceptive Confusion Questionnaire (ICQ; Brewer, Cook, & Bird, 2016) and the Interoceptive Accuracy Scale (IAS) were uncorrelated with the Body Awareness subscale of the Body Perception Questionnaire (BPQ; Porges, 1993), a widely used self-report measure of interoceptive attention. A recent exploratory analysis using the dataset from Murphy et al. (2020) suggested a putative quadratic association between self-reported interoceptive accuracy and attention, whereby both high and low levels of self-reported interoceptive attention (as quantified by the BPQ Body Awareness subscale) are associated with higher self-reported interoceptive accuracy (measured by the IAS and the ICQ). This quadratic association was significant whether the long or short version score of the BPQ Body Awareness was used in the model. Whilst this quadratic association supports the assertion that these measures may assess different constructs (accuracy and attention), it suggests that they appear to be differentially associated at different degrees of attention. The question remains, however, as to what is driving this association; this quadratic association between self-reported interoceptive accuracy and attention may represent a true nonlinear relationship between both constructs or could also be explained due to differences across the questionnaires (e.g. the different internal signals assessed varies across measures). Thus, the present studies have two major goals: 1. Describe the findings from the exploratory analysis examining the quadratic association between self-reported accuracy and attention, using pooled data from several studies reported in Murphy et al. (2020). 2. Confirmatory testing of the quadratic association between self-reported interoceptive accuracy (measured by the IAS and ICQ) and attention (measured by the BPQ Body Awareness), using two new samples that are currently being collected in different countries (Portugal and United Kingdom).