Spooked is hardly a well defined medical term--I'll assume it means "fear of heights".
There could be phyiscal causes, but it can also be psychological. A certain amount of fear of heights is perfectly reasonable--it can protect one from injury or death. And most people become more risk adverse as they age beyond high school.
I used to rock climb. It is a very psychological sport--one has to learn how to control one's fear of heights and regain one's confidence. Many have to retrain themselves both physically and psychologically every spring...
I wouldn't worry about it unless you find the fear paralyzing in mild situations.
And if there is a physical problem, have it treated.
Fear of heights yes............
The fear comes and goes and from time to time I will get scared when there isnt much danger(very rare but it has happend 2 or 3 times). Sunday I went up lonesome lake and over to canon. Right below the summit of canon(just before that stupid coin operated sight seeing thing) my knees turned to jelly abit. I tried to stand there and look over the edge but got freaked and continued on.