Abstract/Summary

The ability to flexibly respond to an ever-changing environment charged with emotional information is essential for effective adaptation and mental health. The Neurovisceral Integration Model (NIM) posits that shared brain areas overlap to support autonomic, emotion, and cognitive regulatory processes, with heart rate variability (HRV) serving as an index of adaptive emotional responding. While prior research has predominantly investigated heart-brain interactions and flexible emotional responses at rest, the principal aim of this thesis was to examine the relationship between HRV and neural and trait affect correlates across both rest and adaptive emotion contexts. In Papers 1 and 2, we demonstrated that task-related and resting HRV exhibited associations with functional coupling of brain areas and dynamic neural networks closely linked to adaptive emotional responding in both younger and older adults. Relatedly, in Paper 3, we found both task-based and resting HRV, but not other emotional disposition variables (i.e., rumination and valence bias), to tentatively predict attentional shifts related to valence aspects of affective flexibility. Collectively, findings from these papers provide some support that HRV reflects adaptive, context-appropriate emotional responding and critically highlight the importance of assessing HRV with associated neural and emotional disposition correlates to elucidate key mechanisms supporting adaptive emotional responding. More broadly, a clearer understanding of HRV and associated flexible emotional responses across contexts has wider implications for HRV as a complementary target for the prevention and/or management of psychological disorders characterised by emotion dysregulation, such as anxiety and depression.