The researchers discovered that when it came to song, although the participants had a hard time recognizing the emotion based on the audio recording alone, once visual cues were added, the observers’ understanding of the emotions the music sought to convey improved dramatically. In contrast, participants were much better able to recognize emotion in speech, whether they were listening to audio alone, watching a video without sound, or seeing both at the same time. As a result, the researchers believe that visual cues play a much more important role in the understanding of the emotions being conveyed by music than they do in the understanding of speech.
To read the full paper in The Quarterly Journal of Experimental Psychology: http://www.tandfonline.com/doi/full/10.1080/17470218.2014.971034#abstract: The research was funded by The Natural Sciences and Engineering Research Council of Canada (NSERC) and by the Canada Research Chairs Program.