Remembrance of happy things past: positive autobiographical memories are intrinsically rewarding and valuable, but not in depression

INTENTIONAL ACTIVITIES TO BOOST POSITIVE EMOTIONS Positive emotion remains a core topic within positive psychology (Fredrickson, 2001, 2013). Itself a marker of the optimal well-being, positive emotion not only undoes negative emotions, but also broadens positive thinking and activities, builds invaluable resources and relationships, and therefore ultimately promotes further positive emotions (Fredrickson, 2001, 2013). Fortunately, beyond comparatively unmodifiable genetic and environmental factors, people can actively engage in many intentional activities to increase their positive emotions (Lyubomirsky et al., 2005). For instance, pursuing self-concordant goals (Sheldon, 2014), expressing gratitude (Seligman, 2011), counting one’s blessings (Lyubomirsky et al., 2005), and retrieving positive memories (Rusting and DeHart, 2000; Joormann and Siemer, 2004; Duckworth et al., 2005; Joormann et al., 2007; for many other activities, see Ben-Shahar T 2010 Even happier: a gratitude journal for daily joy and lasting fulfillment. New York: McGraw-Hill). Notably, amongst these intentional activities, retrieving positive memories has been gaining more and more research interest. Traditionally this strategy was employed to induce positive emotions in psychological experiments (Rusting and DeHart, 2000). It has only recently been suggested that this strategy may be useful in mood regulation (Joormann and Siemer, 2004; Duckworth et al., 2005; Joormann et al., 2007). A recent study (Speer et al., 2014) further justified this effectiveness by uncovering the underlying neural mechanism.