Putting the Body Back Together: A Functional Autonomic Model of Interoception

The ability to sense the internal state of one's body is the process of interoception and is a marker for positive emotional outcomes. The last five years have seen burgeoning research interest in interoception, including a call for more integrative and predictive biomarkers for interoceptive ability. While there is a robust literature purporting to measure interoception, there is also significant research challenging the content validity of the current methodology. Beyond these published challenges, I offer a broader critique that suggests that the current reductionist approach fails to capture the integrative nature of interoception. I introduce an alternate methodology to assess interoceptive ability that leverages the integrative nature of the autonomic nervous system. Thirty-four undergraduates provided real-time feedback about their subjective state of arousal while watching three videos of varying intensity. Across subjects, arousal feedback did not positively correlate with physiological indices of sympathetic arousal including electrodermal activity and the inverse of pre-ejection period. However, each subject appeared to have an idiographic pattern of physiological variables that correlated strongly, although often negatively, with the subjective slider feedback. These physiological patterns provide the foundation for investigating a new biomarker for interoception that relies on the autonomic nervous system to surmise interoceptive states.