When I meet a horse that is very high strung and nervous, there are two questions I ask the owner:
1) Have you tried magnesium supplementation? Studies done in Europe have shown that roughly 20% of horses suffer from a magnesium deficiency. Symptoms include hypersensitivity to touch, and nervousness. Your horse might appear very scatterbrained and really be suffering from a nutritional deficit.
2) Has your horse had a blow to the poll? When the occipital (poll) bones are misaligned, the only symptoms might be in the horses’ behavior. When I explore the poll, I will find an unevenness that can be corrected through myofascial release. Within minutes, you can see a change in attitude.