The emotionally charged story recounted at the beginning Dr. Paul Zak's film—of a terminally ill two-year-old named Ben and his father—offers a simple yet remarkable case study in how the human brain responds to effective storytelling.

   As part of his study, Dr. Zak, a founding pioneer in the emerging field of neuroeconomics, closely monitored the neural activity of hundreds of people who viewed Ben's story.

   What he discovered is that even the simplest narrative, if it is highly engaging and follows the classic dramatic arc outlined by the German playwright Gustav Freytag, can evoke powerful empathic responses associated with specific neurochemicals, namely cortisol and oxytocin.

   Those brain responses, in turn, can translate readily into concrete action—in the case of Dr. Zak's study subjects, generous donations to charity and even monetary gifts to fellow participants.

   By contrast, stories that fail to follow the dramatic arc of rising action/climax/denouement—no matter how outwardly happy or pleasant those stories may be—elicit little if any emotional or chemical response, and correspond to a similar absence of action.