After observing my chickens up close all this time, it's apparent that they and other animals share some of the same neurological issues we have. We've long understood dogs have complex feelings and perceptions. So we should be applying some of the same coping mechanisms to them as we do to humans.
One of them I incorporate in my technique to treat bullying in the article
@Eggcessive just linked to. Basically, what we're doing is to reduce the size and amount of stimuli the animal must deal with. Temple Grandon did some amazing studies on cows being sent to slaughter to determine the stress they experience and how to reduce the amount of terrifying sounds and sights that get them into a terrified state, which releases stress hormones, souring the meat.
Therefore, a dog with a high strung nervous system would also benefit by reducing the size of their world, sounds, and environmental stimuli. I use a few of these myself - ear plugs and dark glasses when I need to shop at Walmart. It creates an emotional "pod" with more manageable stimuli. You would need to experiment to find what works for your sensitive animal as no two beings are the same.