Like people, not all dogs are extroverts. Some dogs are worriers. New situations can be scary and make a nervous dog tremble and shake with fear. Some dogs are so anxious that seemingly normal household activities like vacuuming can be a seriously traumatic event.
If your dogs cowers, hides, or trembles in fear, he is letting you know that he views whatever is happening as potentially dangerous, threatening, or painful. Dogs that have been abused or have experienced some other traumatic event often are extremely fearful. However, don’t assume that every dog that cowers or trembles has been abused. My dog Cami has had the world’s cushiest life and hasn’t been abused. She is just shy; it’s part of her personality and who she is.
If you have a shy dog who reacts fearfully to everyday situations, you can take a few steps to help him become more confident. Extreme fear can lead to desperate escape attempts, urination, or even fear biting, so helping Rover learn to cope is good for the entire family, not just Rover.
To increase your dog’s confidence, you want to give him opportunities to be successful at remaining calm during situations he finds stressful. This technique is called desensitization and involves incrementally exposing your dog to the object or situation he fears. You increase the stimulation very gradually so the dog can slowly learn that, for example, the vacuum cleaner is not an evil entity that wants to kill him.
In this situation, you might leave the vacuum out in a low-traffic room for a few days. At first, the dog might avoid the room, but eventually he’ll cross the threshold. When you see that, give him a treat. Since most dogs are curious, eventually, the dog may lean in and sniff the vacuum. At that point, give him another treat. After he feels okay about that, try telling him to sit next to the vacuum and stay for 30 seconds. Then give him a treat. The goal is to reward calm behavior.
Eventually, you can work up to actually turning on the machine. You still want to go slowly however because you never want to have the dog become overly fearful during the desensitization process. If that happens, you often practically have to start over from the beginning. For example, the first time you could vacuum while the dog’s outside. The dog may try and hide. But the next time you do it, he might not hide because he now knows the sound. After he’s adjusted to that, later, you might try vacuuming while the dog is on another floor. Then the same floor, and so on, until you can vacuum without the dog caring about it at all.
Fear is stressful for dogs, and some dogs are so anxious that they can’t focus enough to deal with any behavior modification or desensitization techniques. In these cases, veterinarians may suggest prescribing anti-anxiety medication to "take the edge off" so the owner can work with the dog more effectively. The drugs aren’t a cure, but by decreasing the anxiety level, the dog can learn.
As noted, biting can be the result of extreme fear. If your dog becomes aggressive because he’s extremely anxious and afraid, you need to get professional help from an experienced canine behaviorist. But for dogs that are just shy, a little patience on your part can help your dog develop the confidence he needs to lead a happy life.