I like to observe...especially people and how the act and interact. Given my penchant for tickling I've pondered this question myself more than a few times!😀
I have a friend who likes to say: "There are no absolutes" and that especiall holds true to we human beings. There are, however, several generalities that do apply from what I have seen:
1) "Playfullness"...people who are always laughing, fooling around, wrestling, etc. These people tend to the ticklish side of the meter. They are usually more open to all sense and live life to the fullest. I think their awareness of their sense makes them ticklish whether they like it or not! LOL
2) "Shy"...people who are very quiet and tend to avoid the rough housing. In my personal experiences they are trying to avoid the overload of sense, or in other words they are the opposite of the playful people. Now these are social outcasts, just the quiet, keep to themselves type. The majority I know (knew) were very ticklish. I always assumed it was because they were ALSO highly in tune with all of their senses, but in their case it was as a defense mechanism. They had to be aware of their body at all times incase thier personal space was violated.
3) "Touchers"...the people who always have to touch someone when they talk, etc. Again, very in tune with their sense of touch. They love the feel of human contact and allow the sensations to wash over them. Usually ticklish in my experiences, but also more likely to just enjoy the feeling without having a wild ticklish reaction.
In general smarts (or lack their of) never seemed to be a good judge. From what I gathered it is more about personality and mind set no matter what the back ground or intellectual level the person was coming from.
Of course that's just my opinion...and I'm usually right dagnabit!😉
~ toyou