Motivational music has been used by the military for centuries, but in modern wars, soldiers are bringing their own playlists

It was a throwaway statistic in an article about the heavy metal band Slayer that got Jonathan Pieslak thinking. During the Gulf war, he read, some 40% of the band's fan mail came from soldiers stationed in the Middle East.

Professor Pieslak is a music theorist at the City College of New York. Over the past few years he has interviewed US soldiers about the music they listen to and – more importantly – what they listen to it for.

You wouldn't expect much Chris de Burgh or Barry White to come floating over the barbed wire fences around military camps in Iraq or Afghanistan, and Pieslak's research confirms the hunch. The playlists are dominated by Slayer, Metallica, Eminem and others.

What's interesting about the work is not so much which bands soldiers are drawn to, but the extraordinary terms they use to describe the power the music has over them. Some talk about tracks turning them into monsters, making them inhuman so they can do inhuman acts.

The subjects of Pieslak's interviews are among the first generation to take MP3 players to war. Some, only half joking, say iPods should be standard issue for soldiers. The psychological effect the music has, and highly stressful situations, make for a powerful mix.

There's some fascinating psychology and ethics in this, but also questions for neuroscientists. How does the combination of the group, a stressful situation, and very specific tracks, or types of music, combine to produce such a powerful motivational, even transformative effect?

What does this tell us about people listening to this kind of music in their daily lives as civilians?

Pieslak has kindly made some of his audio files available for us to post. We also interview him on this week's science podcast.

The audio files we don't include in the podcast are added below.













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