Nylock the Neurologists are probably right, and the kicker is the frequency of the attacks and the sudden onset of the symptoms, and their aviation risky nature. - thats the part that has the aviation doctors having to exclude you.
What interests me most is how you flew commercially for 20 years and then suddenly came down with the condition.
What was it about your pathophysiology that has led to the problem occurring now? Unfortunately if they can answer that and help you, the diagnosis still hangs over you. reversible causes of vasospasm, postural effects of neck position, unequaised pressure effects and so on...quite a mystery.