Navigating the waters of adulthood while living on the autistic spectrum. I'm university student in Western Canada, suffering through the sea of challenging social interactions undertaken by us "grown ups" on a regular basis and trying my best to adapt to change.
The best answer I've ever heard to this question is from autisticdrift on tumblr (their tumblr is linked here). Autisticdrift responded:
It’s different for everyone. Some people withdraw and get very quiet. Others appear to be really angry (throwing or hitting things, yelling, cursing). Others seem very sad/distressed (crying, sobbing, not talking or seeming inconsolable). Some people try to “disappear” by making themselves small, covering themselves with blankets or wedging themselves into a small hiding place.
I don’t think there is a typical response across all people but I do think that each person has a response that is typical of them, if that makes sense.
For me, meltdowns start LOUD and ANGRY, with crying, yelling, throwing, and hitting. Meltdowns are an out-of-body experience and I honestly don't comprehend myself or the situation when I'm having one. I know I scream and cry and wail because I've seen it on video tape (my parents used to tape them when I was a kid because they didn't understand them and wanted to show my doctors) but I honestly have little recollection afterward. I cry and I scream and I throw and then I shrink down into a tiny little quiet shell of myself. I try to hide and make myself invisible.
That is the progression of every meltdown I have ever had from early childhood until now.
Meltdowns are a really unique experience and something that neurotypical individuals cannot usually understand.
The most important thing I want to get across, though, is that meltdowns are not temper-tantrums. Meltdowns are different. Meltdowns are a response instigated by our unique neurochemistry. They are not voluntary.
When I am having a meltdown, I am not really there.