Vagus Nerve Info (head tossing)

Does anyone hahve any info on the vagus nerve and it's role/effects on a horse. I tried doing some research on google and came up with nothing. Im looking for some guidance on how allergies affect the vagus nerve and if that causes ead tossing.

Thanks in advance!

Bump for the morning crowd (morning for me at least...)

Nothing at all?

I'll be on one of the "should I wear a helmet", "Pat Parrelli", or "shood I breede my purty mare" threads...