7!Try this one....
View attachment 74472
Depends on what you look at. Doesn't say to concentrate on the horizontal or vertical ones. If you look at the patterns in the gray background, you can see hints of curved lines in some of the lighter colors, particularly of you back up some.There are no curved lines. Focus on one line at a time and use your mouse to trace each horizontal and each vertical line and you will see they are all straight. It is a weird illusion though.
The illusion is supposed to be that all the lines are straight but "look" like they are curving randomly all over the place. I've seen this illusion before.Depends on what you look at. Doesn't say to concentrate on the horizontal or vertical ones. If you look at the patterns in the gray background, you can see hints of curved lines in some of the lighter colors, particularly of you back up some.
The curved line is the path my eyes are making going around in circles.
True, just thinking outside the box since the instructions weren't "specific"...The illusion is supposed to be that all the lines are straight but "look" like they are curving randomly all over the place. I've seen this illusion before.