Buyer Beware: The subtle manipulation of earworms

We've all been there, when a song pops into your head and suddenly you're humming it without even thinking.But earworms aren't always innocent, advertisers have long understood the power of music. A catchy jingle can build brand recognition in seconds, and long after we've seen an ad the tune is still in our heard, and so is the product.So could the soundtrack in your head be shaping more of your decisions than you realise?