Why haven't scientists solved headshaking in horses yet? 

They know it's a cranial nerve problem. Yet when scientists inspect the nerves, they can't find anything wrong.

That's because it's a nerve transmission problem, rather than a problem with the nerve itself.

Care for the full explanation? 

It's on today's Horse Mysteries Solved? podcast.

Links Mentioned:

https://www.tuckerbiokinetic.com

https://wheredoesmyhorsehurt.com/practitioners/

Cheers to the truth getting out,

Renee Tucker, DVM

Tucker BioKinetic University