Stuck Between an Inflexible Heart and Mind: Examining Heart Rate Variability, Cognitive and Emotion Flexibility in Relation to Internalizing Symptoms

Individuals with internalizing disorders (e.g., anxiety, depression) often exhibit difficulties with cognitive and emotion flexibility. Cognitive flexibility is an important control mechanism for adapting human thought and action, while emotion flexibility enables regulation of emotional perception and reactions. Laboratory-based tasks involving cued flexible thinking do not adequately capture an individual’s ability to adapt to environmental changes without guidance or represent the extent to which individuals must exert flexibility in daily life. Thus, researchers need to examine more ecologically valid measures of flexibility in relation to symptoms of internalizing disorders. We developed a novel item-generation task to assess how individuals flexibly generated thoughts within and across cognitive and emotional domains. While flexibility with cognitions and emotions is important for effective adaptation to environmental changes, heart rate variability (HRV), the fluctuations in the time between heart beats, provides a non-invasive measure of autonomic nervous system functioning in response to stressors, both in the laboratory as well as with wearable devices. Using an unselected sample of undergraduate students (n=110, 18-22 years old, 58 % female), we characterized how cognitive and emotion flexibility uniquely relate to clinical symptoms of anxiety. In addition, we characterized both lab-based and ambulatory measures of vagally-mediated HRV in relation to cognitive and emotion flexibility using the novel item-generation. Overall, results indicate that performance on the item-generation task was related to standardized measures of cognitive flexibility. While HRV during the task was not related to performance, higher HRV during a control task prior to item-generation predicted better performance across most trial types. Finally, performance was also related to self-report symptoms of anxiety, although this relationship was more robust in dual category conditions. Limitations and clinical implications of the findings are discussed.