Why do theme songs pull at my heart strings?

I recently watched The Inbetweeners for the first time. It follows the lives of four teenage boys at sixth form and it is VERY FUNNY. Described as an anti-Skins – i.e. these kids are normal – it follows Jay, Simon, Will and Neil as they embark on the final years of their school life and a desperate bid to lose their virginity.

Like I said, it is VERY FUNNY and I fully recommend it. I’m writing though because it has one of those theme tunes that I stirs my emotions when I hear it. It’s by a band called MorningRunner – they are now defunct – and is little more than a guitar tune with three notes on a piano thrown in. It got me thinking; does a theme tune only become emotional if the programme it’s on means something to you? Or can you vehemently hate a show and still find yourself balling your eyes out during the opening credits?

Anyway, here’s the song. (It’s instrumental on the show – I’m not sure it’s so good with lyrics.)