Mouse scroll wheel in album grid layout not working properly (no backward scrolling)

In the album "grid" layout, when you click a picture to enlarge, you can use your mouse's scroll wheel to scroll through the images. Unfortunately, no matter which way you scroll, you'll always advance to the next image, instead of  being able to go back to the previous image when reversing the scrolling direction.

Example: http://imgur.com/a/cbILa/layout/grid#3 (try scrolling up and down with your mouse)