This research investigated whether the physical act of enclosing an emotionally laden stimulus can help alleviate the associated negative emotions. Four experiments found support for this claim. In the first two experiments, emotional negativity was reduced for participants who placed a written recollection of a regretted past decision or unsatisfied strong desire inside an envelope. A further experiment showed that enclosing a stimulus unrelated to the emotional experience did not have the same effect. Finally, we showed that the effect was not driven by participants simply doing something extra with the materials, and that the effect of physical enclosure was mediated by the psychological closure that participants felt toward the event.
"Pack all your troubles in your old kit bag and smile, smile, smile"