(PS3-23) Loneliness and Its Relationships with Reward Learning and Physical Activity

Loneliness is the aversive feeling of being alone that arises from the subjective perception of unsatisfactory social relationships. Given that loneliness is a predictor of higher depressive and anxiety symptoms, investigating its relationship with other variables may help improve these symptoms. In the existing literature, one risk factor for loneliness is decreased functioning of the reward system. Potential protective factors for loneliness have also been identified, such as physical activity, which has been shown to be inversely correlated with loneliness. Though existing literature has investigated reward processing and its relationships with loneliness and physical activity, reward processing has multiple components. Reward learning is a particular facet of interest, so to narrow down previously established relationships we specifically aimed to examine how loneliness relates to reward learning.

This project used baseline data (n = 26) from a randomized controlled trial that compared a positive and negative affect treatment (Craske et al., 2023). In this secondary analysis we examined relationships between loneliness, physical activity, and reward learning at baseline through a series of regression models. Loneliness was measured using the UCLA Loneliness Scale and physical activity was measured using actigraphy and operationalized as average caloric expenditure. Reward learning was measured using response bias towards the more frequently rewarded stimulus during a probabilistic reward task. We hypothesized that greater baseline loneliness would predict lower levels of physical activity and blunted reward learning.

We found that baseline loneliness did not significantly predict baseline physical activity (p = 0.42) or baseline reward learning (p = 0.68). Since our results were not significant, it is possible that another component of reward processing has a stronger relationship with loneliness than reward learning does. There may also be additional processes not included in our analyses that affect relationships among loneliness, physical activity, and reward learning. Limitations for our project include a small sample size and potential inconsistencies regarding actigraphy measures of physical activity. Future work could explore additional components of reward processing, utilize a larger sample size and longitudinal data, and collect additional measures of physical activity. Understanding these relationships could help inform potential new treatments for decreasing loneliness and related psychopathology.