Wellbeing begins with "we" not "me" psychosocial benefits of gratitude interventions

In recent years there has been an unprecedented, widespread endorsement and application of interventions designed to foster gratitude. However, rigorous experimental research into the efficacy of gratitude interventions is only in its formative stages and much work is needed to determine not only if they are effective, but also how and when they are effective. Additionally, despite the inherently social nature of gratitude and robust evidence that social relationships are a key determinant of wellbeing, no research has utilized social or interpersonal gratitude as a strategy for improving wellbeing. This thesis, therefore, examines whether interpersonal gratitude interventions improve how people perceive their relationships with others and their overall wellbeing, and if so, how and when. Three research articles are presented in this thesis detailing the results of three robust, longitudinal randomised controlled trials. The key findings that emerged were, firstly, that shifting the focus of gratitude towards others leads to enhanced psychosocial wellbeing, compared to self-focused gratitude and neutral control activities. Secondly, these findings uniquely contribute to theoretical understandings of how gratitude interventions work by offering novel mechanistic evidence in support of both the broaden-and-build theory of positive emotions and the find-remind-bind theory of gratitude. Gratitude appears to promote the maintenance and development of existing social relationships and friendships, which in turn improves markers of wellbeing. Thirdly, this thesis informs and updates the Positive Activity Model by examining intervention features (self vs. other oriented, behavioural vs. reflective) and person features (pre-existing levels of social support and depression) that would likely influence intervention efficacy. This thesis extends current knowledge and adds to a growing body of work emphasising the social and psychological benefits of being grateful, and the potential of gratitude interventions to foster positive mental health and wellbeing.