In addition to the six mechanisms by which emotion is evoked, as pointed out by Juslin & Västfjäll (J&V), we believe that there is another mechanism by which music may elicit emotional responses: semantic association. Music may activate meaningful concepts that give rise to an emotional response. Some musical information has a defined meaning, such as the drum figures of many African cultures that go way beyond speech mimicking (Nzewi et al. Reference Nzewi, Anyahuru and Ohiaraumunna2001), Wagner's wedding march, or a national anthem. Other musical information might evoke associations to meaningful concepts because it resembles the sound or the quality of an object, or because it represents stereotypical forms (e.g., a church anthem and the word devotion). Because many of these semantic concepts also have an emotional connotation, a decoding of such concepts may elicit an emotional response (Steinbeis & Koelsch, Reference Steinbeis and Koelsch2008).

Moreover, emotional contagion was defined by Hatfield et al. (Reference Hatfield, Cacioppo and Rapson1994) as a “tendency to automatically mimic and synchronize facial expressions, vocalizations, postures and movements with those of another person and, consequently, to converge emotionally” (p. 5). Although no satisfactory account on the workings of emotional contagion has yet been proposed (as noted by J&V), considerable effort has been invested into the investigation of mental processes underlying empathy, including emotional contagion. In this context, earlier work by Lipps (Reference Lipps1903) and Merleau-Ponty (Reference Merleau-Ponty1966) that already anticipated mutual mental facilities for perception and action has been rediscovered. “Common-coding” (Prinz Reference Prinz and Prinz1990), “simulation theory” (Carruthers & Smith Reference Carruthers and Smith1996; Gordon et al. Reference Gordon, Davies and Stone1995), and the “perception-action model of empathy” (Preston & de Waal 2003) are concepts proposed by more recent lines of research that can also account for mental mechanisms underlying emotional contagion. During the investigation of mirror neurons in recent years, some progress has been achieved that may offer perspectives on a neural substrate underlying this phenomenon (see the target article): Mirror neurons seem to discharge both during an action and during the perception of an action, even in the auditory domain (Kohler et al. Reference Kohler, Keysers, Umilta, Fogassi, Gallese and Rizzolatti2002).

We agree with J&V that emotional contagion plays a role in music processing, but we would also like to complement their conception: Whereas the current opinion seems to be that emotional contagion, and its underlying neural mirror system, is an immediate mechanism, recent data suggest that emotional contagion may actually have a temporal dynamic of activation (Koelsch et al. Reference Koelsch, Fritz, von Cramon, Müller and Friederici2006). In the Koelsch et al. study, an auditory mirror mechanism (premotor activation of the larynx representation) was activated by the perception of musical stimuli with positive emotional valence. This mechanism was not immediate, but instead was shown to be increasingly engaged with the duration of the pleasant music stimuli, so that it showed a robust engagement of premotor regions between 30 seconds of music listening until the end of the stimuli that lasted for approximately 60 seconds. Such “auditory mirror resonance” was not involved during the perception of aversive, unpleasantly modified musical stimuli. This corresponds to the concept of emotional contagion, in that the latter is likely more strongly associated with approach behaviour (when, for example, attention is directed towards others) than with withdrawal behaviour (brought about by the perception of unsettling information) (Hatfield et al. Reference Hatfield, Cacioppo and Rapson1994). This supports the idea that this mechanism may indeed correspond to a neural underpinning of emotional contagion. Because the engagement of the neural mechanism putatively underlying emotional contagion was related to emotional valence, and because it showed a temporal dynamic of activation, it is likely that emotional contagion is a more complex mechanism serving music processing than previously assumed.