“Dogs enjoy that a lot more than the tickle we all tend to do, and theyre likely to do a lot more.”
But according to Sarah patting a dog on the head isnt the only thing we need to be careful about.
It turns out patting a dog on the head is actually very rude in dog language
She says: “Another thing to think about is if a dog rolls onto their back and shows their belly, we all love to give them a belly scratch.
Sarah Bartlett , qualified international dog training instructor, has shed some light on why you shouldnt pat a dog on the head.
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Many dogs dislike being touched or patted on the top of the head. All it takes is a quick search on the internet to see countless photos of dogs showing stressed body language while being patted on the head. Body language signals your dog might exhibit are ducking away, lowering of the head, stepping away, putting the ears back, licking lips, or whale eye (whites of eyes visible).
Humans seem to be disposed to want to pat a dog on the head; this is likely for several reasons. A dog’s head is usually the closest part of the dog we can reach. For some dogs, we don’t even have to bend down to reach our dog’s head. Humans seem to mimic this behavior from other humans. Think of a parent lovingly stroking their child’s hair. Children may enjoy this, but most dogs do not.
Humans can also be quite rough when patting a dog on the head, and it may not be an enjoyable experience for your dog. Coupled with the fact that dogs inherently dislike something reaching down from above toward them, most dogs quickly learn to associate a hand reaching toward their head with discomfort or stress. This leads many dogs to become head shy, and they learn to duck out of the way of a hand reaching toward them. 
This can be an annoyance when you have to follow your dog across the room to put on his leash, or even downright dangerous if you need to grab your dog in an emergency and he ducks away from you.
But the good news is there are many things that you can do to prevent head shyness and even give your dog a positive association with someone reaching toward his head.
Once it’s aware of your presence, lower yourself to their level, but make sure you give them space and let the dog choose whether or not it wants to come to you.
Meanwhile this is the controversial moment a dog trainer lets his sons, aged two and six, wear a “bite sleeve” while being savaged by a 13 STONE pitbull called Hulk.
Rather than their head, dog experts at Vet Street recommend stroking their chest, shoulders, the base of the neck and under the chin.
Though remember to reach in from the side rather than from above, so the dog doesn’t feel threatened, and be gentle, as this is calming and likely to make them keen for more.
Rather than a gesture of affection, patting a pooch on the head can actually be perceived by the dog as threatening behaviour.