Two of the mechanisms Juslin & Västfjäll (J&V) identify that are critical to music's ability to generate emotions rely particularly on memory processes. Evaluative conditioning involves unconscious processes: Through repeated pairings, people learn associations between particular pieces of music and pleasant or unpleasant events. Conscious episodic memories may also yield emotional responses: Music often evokes memories, thereby also evoking the emotions associated with those memories. Although these discussions of memory processes are compelling, they are incomplete because they exclude mention of the many circumstances in which music is explicitly associated with narrative content that independently generates emotional responses. For example, music is often accompanied by lyrics that tell stories with overt emotional messages (Ali & Peynircioglu Reference Ali and Peynircioglu2006; Morton & Trehub Reference Morton and Trehub2007; Stratton & Zalanowski Reference Stratton and Zalanowski1994). Our particular focus, however, is on circumstances in which music is associated with the narrative content of film.

Consider John Williams's famous theme from the movie Jaws (1975). The film provides viewers with an opportunity to associate a particular piece of music – a repetition of two notes in an ascending pattern – with the narrative arrival of the Great White Shark. This pairing isn't accidental. Williams's theme, presumably, is intended to match or amplify the narrative content. Moreover, as the film progresses, the music begins to foreshadow particular narrative content. More generally, it seems quite likely that people acquire correlations between types of music and types of narrative situations. Those correlations are presumably more consistent than those implied by J&V's discussion of evaluative conditioning and episodic memory.

Research on film strongly suggests that emotional music has a reliable effect on viewers' interpretation of narrative content. For example, Vitouch (Reference Vitouch2001) asked participants to view the opening scene of a film accompanied by music pre-tested to convey either positive or negative affect. Participants then wrote open-ended continuations of the narrative. Analyses revealed that the plot continuations were colored by the emotional content of the opening scene's music: The positive music made participants more likely to use happy words in their continuations and the negative music made participants more likely to use sad words. Given the same visual information, modifying the emotion of the musical soundtrack caused differences in viewers' expectations about how the narrative would unfold.

Even when it does not occur concurrently with the main action of a scene, music can influence viewers' perceptions of film narrative. Tan et al. (Reference Tan, Spackman and Bezdek2007) paired scenes of characters displaying neutral emotions – sampled from commercial films – with music that participants in an earlier study had rated as happy, sad, angry, or fearful (Spackman et al. Reference Spackman, Fujiki, Brinton, Nelson and Allen2005). However, the music did not accompany the character's actions. Rather, the music occurred either before or after the character appeared on screen. In addition, the experiment's instructions asked participants to focus their attention toward the visual techniques, such as changes in lighting, that directors use to convey emotions. Thus, participants were discouraged from attending directly to the music. After viewing each film, participants evaluated the emotions of the characters on several scales. Even though the music was presented before or after the actor was onscreen, participants' judgments of characters' emotions were consistent with the emotional content of the music. Emotional attributions were stronger for music presented before a scene than for music presented after a scene. The music provided viewers with interpretations of the characters' neutral affect.

Music can also establish a context for understanding films through broader associations (Boltz Reference Boltz2004). For example, Bullerjahn and Güldenring (Reference Bullerjahn and Güldenring1994) commissioned original musical scores representative of several different genres, such as crime and melodrama, to accompany the same 10-minute film. Participants viewed the film with one of the scores and completed open-ended questionnaires about the intentions and relationships of the characters. Changes in the emotional content of the music brought about differences in how participants interpreted the film. An encounter with the “crime” soundtrack, for example, led some participants to attribute violent intentions to the characters in the film. This study suggests that film music genres can serve as an emotional framework, preparing viewers for what they are likely to experience during the narrative.

Finally, researchers have documented processing consequences for matches versus mismatches between the emotional content of film music and the emotional content of narrative elements. For example, in a study by Boltz et al. (Reference Boltz, Schulkind and Kantra1991), participants showed greater recall for films in which music emotions and narrative emotions matched than for films in which one was positive and the other was negative. When music was played before the outcome of a scene, the opposite effect was observed: A mismatch in emotions led to better overall recall, possibly because of the surprise generated by expectancy violations. Subsequent research suggested that participants encoded emotionally matched music and narrative elements into integrated representations, whereas they encoded emotionally mismatched music and narrative elements separately (Boltz Reference Boltz2004).

One of the strengths of J&V's analysis is the focus on the developmental trajectories of the collection of mechanisms they outline. The studies we have described support rather strongly the conclusion that adults make use of associations between types of music and types of narrative content to generate expectations or interpretations of film narrative. However, the studies do not indicate how much experience, if any, is necessary for music to begin to function in this fashion. We can wonder, that is, at what age children begin to perceive matches or mismatches between emotional music and narrative content. Note also that the research we reviewed examined the extent to which emotional music has an impact on viewers' interpretation of narrative. We could also wonder, as another topic for developmental research, to what extent experiences of narrative content have an impact on the extent to which viewers perceive music as having a particular emotional tone. Over time, as J&V have suggested, music could retain its emotional tone independent of its original narrative context.