iTunes showing wrong artist artwork. how do i find the image and delete it?

iTunes is showing the wrong artwork for an artist. What is strange and frustrating is that the image is not the artwork for any of the artist's albums. iTunes seems to be pulling it from nowhere. I can't figure out where iTunes is pulling the image from. It's a ted talk image.

How do i go about finding where the image is coming from to delete it? Sting gave a ted talk, which i had downloaded, so iTunes may be getting it as a result of that. i deleted the ted talk, deleted all the albums, and then uploaded them again but the image keeps popping up. also tried deleting the artwork cache with no luck. any suggestions besides deleting all of the Sting albums?????