<p>Recent discoveries in Cognitive Science have shown that, given a constant frequency and location, changes can be imperceptible.</p>
<p>The following link contains a collection of images that flicker; in every flicker a change occurs in the photo and it subsequently returns to its original state. This flickering procedes indefinitely; that is, until the viewer notices the change. Try to discover the change in the photos:</p>
<p>One can navigate to other photos by right-clicking on the flickering image, and selecting another stimulus. The ‘Dinner’ scene is most difficult, I think.</p>