Changes in Interoceptive Accuracy in Response to Social and Physical Threat

This thesis examines state changes in interoceptive accuracy in situations characterised by negative affect and heightened self-focus. The experiments manipulate negative affect in social and non-social contexts, by evoking social and physical threat, respectively. State changes in interoceptive and exteroceptive somatosensory perception are simultaneously examined in several experiments comprising the present thesis, in order to establish whether potential changes in the interoceptive modality generalise to the exteroceptive somatosensory modality. The experiments in the current thesis measure interoceptive accuracy using a heartbeat tracking task and assess the perception of exteroceptive bodily signals using cutaneous electrical stimulation. Socially threatening contexts manipulated in the present thesis include ones which: evoke social anxiety (Experiment 1), heighten social awareness of the self (Experiment 2) and result in social rejection (Experiments 3 and 4). Experiment 5 additionally examines the effect of physical threat on interoception by employing a pain anticipation paradigm. The main findings of these experiments indicate that heartbeat tracking accuracy (HTA) increases in response to public speaking anticipation as well as in response to pain anticipation, while it decreases as a result of social exclusion. Social self-focus, manipulated using a video camera being turned on and off, does not affect HTA, nevertheless, increasing the sensitivity in detecting electrotactile stimuli. Overall, the results of the present thesis indicate that interoceptive accuracy functions as a state variable, which changes in response to negative affective contexts that manipulate social and physical threat. It is proposed that interoceptive accuracy changes as a function of affective and social self-focus in these contexts. The findings of the current thesis are important considering the role of interoception in cognitive-affective processing. Future research investigations should explore whether state changes in interoceptive accuracy are accompanied by simultaneous changes in neural activity in the interoceptive regions of the brain, such as the anterior insula.