Beatboxing is a perfect example for me. I only discovered how to do it by accident and only a few months ago, and now I can't stop.
I've had other stims come and go... mostly vocal ones changing from the frankly bizarre noises I made at school to meowing then to turkey sounds then back to meowing..
Sometimes I have stims happen that are just spur of the moment, like certain lights that I can't help staring at and "playing with" by looking at them different ways or blinking etc... hand/arm/body movements that happen without any proper form or meaning because of high levels of emotion (usual excitement, anxiety and rushes of energy)...
Whilst one might "default" to certain stims that have the best effect, stims are things that help with stimulation... if you see someone stimming and enjoying it, you might start copying them to see why they like it so much and maybe pick up those stims. Or other things might make you want to try new ones that then stick. Stims might at times be hard to keep track of, but they're not totally involuntary, so evolution and change depending circumstance, need and satisfaction are pretty easy to imagine happening.
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Stimming, stimming all day long~
Common sense? Me? Hahahahahahaha no. You're more likely to find penguins in the sahara.
We should adapt - but we should not conform.
A life without tea is a life not worth living.
Latest Aspie Quiz: AS - 151, NT - 38 / RAADS-R: 195 / AQ: 38