Lyubomirsky et al., 2004, Study 2, described in Lyubomirsky et al., 2005: Expressing gratitude through writing increased overall happiness among students after six weeks
Lyubomirsky, S., Sousa, L., & Dickerhoof, R. (2004). The medium is the message: The costs and benefits of thinking, writing, and talking about life’s triumphs and defeats. Manuscript submitted for publication.Download PDF
Asking students to reflect on things they are grateful for once a week for 6 weeks increased happiness over this period, as compared both to a no-treatment control group and students asked to think of things they are grateful three times a week.