There is this particular shriek that I make only when being tickled. Well, also when being poked in the side or grabbed just above the knee. From all accounts, once you've heard it, you can't resist trying to goose me into it again. This isn't limited to guys either. Straight women find it fascinating as well but that's another story.
This story goes back to high school, gifted class to be specific. At my high school, those of us in the gifted program had the option to take an every day class or a 4 times a semester seminar. I preferred the class. It made for a nice mental break during the day or a chance to get mentally up to speed if it was first period. Kids from all 4 grades were in the class. While we'd have to solve brainteasers or create skits, we would have plenty of free time in the class to do everything from homework to playing cards.
I have no idea what happened for me to do the shriek in the first place but one guy was entranced. Hell, I'll name names. It was Greg. He was a year behind me. After a few moments, he figured out that if he grabbed my knee and goosed it, he could make me repeat the shriek. As you can guess, I didn't find it all as amusing as him. Even back in high school, I was known for not putting up with certain things so I'd take a swing at whatever part of him I could reach every time he'd grab my knee.
Well, this is where we all learned that a high IQ doesn't equal the ability to predict future behavior and that Einstein was right with his ideas on mental illness. All across the classroom you could hear:
SHRIEK
SMACK
Oooooouuuuch
SHRIEK
SMACK
Oooooouuuuuch
SHRIEK
SMACK
Ooooouuuuch
There was maybe 10 minutes of this before the teacher sighed and called Greg up to her desk and told him to stop making so much noise. I was sitting back trying to laugh quietly when she blamed it all on him.
I'd love to be able to say he learned his lesson but he didn't. We went through it all several times before I graduated.