The effect caused by spending large amounts of time with your instrument/vocal part causing the instrument/parts personality to take over. For example, trumpet players become more self-centered and egocentric, whereas cellists become perfectionists, and the people singing the baritone part mellow out. This can be achieved in varying degrees, but begins to show up the moment someone gets an instrument or vocal part.
Dude, what happened to Todd? He used to be so hyperactive before he joined choir.

Don't worry, he's probably just be suffering from Musician’s Syndrome.
by Hope I. Nobands August 14, 2011
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