What you see in these images is determined by whether you are left or right handed.
Because the brains of left- and right-handers are organised are organised differently, left-handers see and think differently and can get some very different results from various "brain tests". Left -handers tend to do well on tests that involve creative thinking or unraveling complex images and manipulating 3D images.
In the first image a right-hander may just see a hodgepodge of disconnected shapes, but a left-hander will tend to make sense of the shapes. Left-handers are more likely to see the dalmatian shiffing the ground.
The second image is a Kanizsas triangle. If you can see the white triangle - the one with its apex pointing up - it's because your left-handed brain has created that triangle to unify what is otherwise simply a collection of angles and PacMan shapes. There is, in fact, no white triangle there.
Taken from a post for International Left Handers Day 2007