It is not that surprising that music has been shown to reduce stress and distress in some human patients. But who would have thought that mice would be affected by music? But it seems that mice produce and respond to music. According to recent research, male domestic mice (and other species) sing, like songbirds, to attract a mate. Strange to think they might be warbling away beneath the floorboards. Fortunately their song is not audible to humans otherwise it might keep us awake.
Musical mice are also in the news due to recent Japanese research that involved playing opera and Enya to mice that were being subjected to heart transplants (Masateru Uchiyama et al, 2012).You would think the idea for this research might have been a bit of a wild card - but indeed someone's hunch paid off in terms of some interesting results. (But yes, this was tough on the mice and I don't think if I was on the ethics committee I'd have been talked into approving this one.)
Transplant survival increased in the mice that were treated to the non-stop opera (but not the new-age Enya) and there were significant changes in some key immune cells and molecules.
So should we conclude that music boosts your immune system? Not at all - increased transplant survival indicates less rejection - and therefore a less active immune response.
Does this research have an application in terms of human health and recovery? Again, I don't think so. The musical likes and dislikes of mice and humans might, after all, be different. Not to mention the musical preferences of their immune systems.
Should someone be trying to repeat this research on humans? Again the answer is no. You would have to persuade transplant patients to volunteer to put up with non-stop noise (classical, new-age, or just a high pitched sound) for a week before or after their operations. A bit of a non-starter I'd say. And humans are given anti-rejection drugs which would muddy the waters, to say the least.
This is the kind of research that raises lots of questions, many of which may never be answered. But it does highlight that, even in mice, the interaction between the brain and the immune system is more complicated than we can begin to imagine.