Noise Phobia and Going Outside

Galahad has always been noise sensitive, startling at unusual or loud noises but we've always managed to work through it with him. We've been doing desensitization training using CD's and recreating noises of sounds that spook him (fireworks/city sounds/basketballs bouncing) played very quietly and giving him treats/praise for calm behavior. When he gets startled in real life situations we try to redirect him by doing fun tricks with him until his focus is off the noise. This seemed to be working and he was doing really well for a few months, we had him at a point where he barely reacted at all to noises.

A few weeks ago we were on a walk a people set off fireworks on the other end of the open field we were walking across. Gally was very upset and started running as fast as he could for home (on leash). Since that incident he has been getting progressively worse. We took him to sit in the park during the day and tried to get him calm and reward him but this plan backfired as he became afraid of the sound of the people playing soccer across the field. We made a bad decision and tried to restrain him as he was choking himself on the leash instead of just getting up and leaving right away, I now realize that was the wrong thing to do and it has probably made him more afraid of that park.

So this park is just down the street and it is at the point now where Gally doesn't even want to go outside to pee. I know to work on this we need to keep him under threshold and gradually reintroduce him to the sounds and sights of the park with lots of positive reconditioning. At the same time he has to go out at least a few times a day to relieve himself but just going out the front door sends him into a panic which I know will only make it worse. As soon as he's back indoors he "shakes it off" and will appear perfectly normal within a couple minutes, ready to play or take a nap.

He is good indoors (startles to loud noises but recovers quickly) and outside at other locations. If we start our walk from our front door though he will be scared the whole time. He does not like open fields in any location.

We are in the process of getting a behaviorist in to help us make a plan for him as well a working with the vet to see if there is anything we can do medically. We are also working through the Protocal for Relaxation and continuing with training in the home to help build his confidence in himself and us.

Any thoughts, support or similar experiences would be very much appreciated. The stress of the situation has been very frustrating, it can be hard to stay positive which is what I need to do for him.

For more of his history this is the last thread I made regarding this: http://www.dogforums.com/dog-training-forum/109747-afraid-fireworks-other-loud.html