Remove the "Uploaded To" reference in Media

Hi there

I’ve uploaded an image to a post as a featured image. But I decided I didn’t want it, so removed it as the featured image. However my theme (eleven40 child theme for genesis) continues to display the image thumbnail in my archive pages and my home page.

The image is not set as the featured image any more, so I’m guessing it’s getting this association from the media area somehow. When I go to the media management area, I can see that this image has the post name under the column “Uploaded To”. But I can’t see anywhere how to remove this association. My theme must be using this for some reason, rather than the featured image functionality itself.

How can I disassociate this image from the post? If I have to do this in the database then that’s OK – I am familiar with SQL.

Thanks a lot
Brett