Optical Illusion: Can You Spot the Dogs?

Please Read Before Scrolling Down to See the Picture:

Thepicture below was shown to several groups of people who were asked to see how many dogs they could find. Amazingly, in general the men who looked at the photo were able to identify all the dogs at once, while the women seemed to take a little longer. Some as long as five minutes. I'm ashamed to say that I had to look at the picture for quite a while before I was able to see any dogs at all.

Before looking at the picture, I'll give you a hint: the dogs are white with black spots. Have fun, and see how long it takes you to "Spot the
Dogs"