Is it possible to make the contents of your gallery images change the contents of another image block on the page?

I know this is not quite normal, but I know there must be a way to do it. I have a few products in a gallery wall on my site, when I click them they pop up into a Lightbox where you can scroll through them. It shows the description along with the image. Does anyone know if it is possible to have an image block somewhere else on the page change as you select different gallery images? I was hoping that along with the gallery image, I could have the gallery descriptions change the contents of some text beside the image.

 In theory it doesn't seem like it should be all that hard... Any input would be appreciated. Thanks.