Emme has always been strange around men in ball caps. Even if she knows the person and has seen them many times, if they put on a hat, Emme doesn't recognize them. She barks and growls and keeps it up until the hat comes off. Then she is fine. She goes up to the person with no hesitation.
I seldom wear hats so that hasn't been a problem for me but recently I decided that I needed to buy a winter hat to wear instead of the hood on my winter coat. So I went to the outlet mall and bought a winter hat (with ear flaps!) at Eddie Bauer. When I put on the hat in the kitchen, Emme was very unsure. She did not bark or growl and she didn't back away, but she came only hesitantly to me. She could hear my voice and smell that it was me, but with a hat on, I was a suspicious person. As soon as I took off the hat, Emme was fine. How can something as small as a hat cause such a reaction in a dog?