The last paper is something a little bit different and comes from Oliver Sacks, the neurologist and author of several popular books, including 'The Man Who Mistook His Wife for a Hat', in which he outlines some of his more unusual cases. Publishing a piece recently in the journal Brain, Sacks describes the visual musical hallucinations of 8 people who have contacted him regarding their unusual experiences. These people, suffering from a variety of different medical conditions, from glaucoma to Parkinson's Disease, describe seeing phantom musical staves and notation in the world around them: boldly replacing the text in books, floating in the air and over the walls and even, in one case, becoming the printed border on a bathmat.
Remarkably, although 8 of the 9 people outlined in the article have a musical background, it does not appear to be required to experience these unusual phenomena. Christy C, who reports seeing music under a high fever, describes herself as a non-musician.
But what is occurring in the brain during these experiences. Well the advent of accurate brain-scanning technology has allowed us to investigate the neural basis for a variety of functions; reading text for example appears to be associated with a region called the left inferotemporal cortex, but given the differences between text and musical notation, in form and complexity, we can't take for granted that brain areas involved with reading are also employed in the reading of music. Moreover a study from 1992 showed activation of a distinct brain region, the left occiitopareital junction, where the visual cortex at the back of the brain meets the parietal cortex, on the top of the head.
So while the neuroscience behind these highly irregular symptoms is unknown is does give us a sense that our brains are highly impacted by our experiences and interests. The article is wonderfully well written and is packed full of interesting comments about our interpretations of musical text.
I think readers who enjoyed this article might like to take a look at Oliver Sacks' 2007 book Musicophilia: Tales of Music and the Brain, which is a beautifully written account of Sacks' interactions with patients experiencing the power of music. It really highlights the effect that music can have on the brain turn how this influence plays out when our brains are damaged.