A few autistics I know do this all the time, including myself. I just cling my arms to my chest and bend my wrists down, kind of like a T-Rex.
"You do it all the time." Said one autistic guy I know.
"So do you!" Was my reply, and then we laugh at each other.
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Shedding your shell can be hard.
Diagnosed Level 1 autism, Tourettes + ADHD + OCD age 9, recovering Borderline personality disorder (age 16)