One commonly known trait of autism is fear of change. Reaction to change can be extreme, e.g. a 'meltdown', or mild, such as slight anxiety. It's usually inherent, but also adaptive.
As a child and through early adulthood, I did not deal well with change. It always induced anxiety. Most times it manifested in a controlled way: part or complete shutdown. I just completely withdrew into myself and shut my mind and body 'off'. A few times it resulted in stomping, angry yelling, shaking, sweating, and/or crying. Commonly called 'tantrums'. But it was rarely explosive (mostly due to consistent shaming "Girls don't act that way!"*).
I remember my mother telling the adult me on the phone once, "You don't like change, do you." It wasn't a question; it was a statement. I realized she was right. Remembering something I saw on the TV a few years prior helped me to try and address that.
During torrential flooding from a massive storm in California may years before, a river overflowed it's banks and flooded a town. A media crew in a boat was filming the damage and talking about it. As they floated past a house with water nearly up to the eaves, they asked a man on the roof what it was like. He smiled and calmly said "Change is good!!".
That 30-second film clip is anchored in my brain. I reach for and use it whenever a big change is expected or pops up unexpectedly. It sets a stage for me to navigate through a change, be it having to go to a new doctor, moving across the country, losing my funding for research and finding a new position, going to a place I haven't been before, etc. Especially a change in routine. For example, unable to follow my gym schedule (this really upsets me) due to an illness or other demand.
A more recent huge change was retiring from academia. I'm still dealing with that 10 years later, but better than immediately afterwards. Another was changing my post-retirement routine, which was travelling around the country for nine years in my travel trailer and working at wildlife refuges. The latter was a sacrifice for my daughter and her family, and one I would not have made for anyone else. I'm still trying to adapt to that, too.
Being an adult with late-identified Asperger's, I had already established ways to mitigate many of my Asperger's idiosyncrasies. One is by masking my behavior (especially in academia). But that comes at a cost when done for too long. The edges start crumbling and people say I'm edgy and irritated. Or I'll shut down: I turn into a zombie. If I don't get a reprieve, I blow up.
Some people ask me how I handled traveling around the country so often if I am on the autism spectrum. "You're not afraid of change! You can't be autistic.". That's not exactly correct. I'm not 'afraid' of change because logically I now know and accept that life is full of change. But I can get anxious about change. Sometimes more than others. And, after 5 decades I've learned ways to cope. Most times.
One is anticipation and expectation. If I know a change is coming, I plan for it. Often to the minute details. It then becomes a sequential adaptation. For my trips across country, I would plan routes, timing, location and time stops for gas, overnight stops, and arrivals. My biggest anxiety was breakdowns (which did happen once).
Unanticipated changes are slightly different. If it involves sensory changes, it has more immediate responses that I can't control. Such as flashing lights, loud sounds, etc. "Everybody does!", you might think. Sure, but do they cause extreme physical and mental reactions that last too long? Does a loud muffler cause your entire body to shake, lose your balance, and your head feeling like it's going to explode for several minutes? Does a child's screaming sear your brain like hot pokers? (think of someone putting your head next to a fire siren) Do flashes of bright light cause you to lose balance and make you nauseous? Does constant dog barking feel like a hammer beating your head? If someone grabs/hugs/or touches me unexpectantly, I'll flail and back away in a 'fight or flight' response. (Please don't hug me.)
Sensory perception, integration and/or processing are different for many on the AS. Learning about how the autistic brain is wired differently than neurotypical brains and how to mitigate reactions to triggers helps. I wear sunglasses a lot, my regular glasses have a tint to negate fluorescent lights, and are progressive darkening. I carry noise canceling ear plugs all the time.
The last 40+ years have been forcefully camouflaging myself to be like the neurotypical 'normal'. But it has never been my 'normal'; rarely being myself. It's like wearing a costume most of the time. And it's exhausting. Meeting other neurodivergent people has been an awakening that I'm not alone.
I now feel affirmed and courageous enough to ask people not to hug me or to ask first. (wish I had a shirt that read, "Please respect my personal space") Most times I compromise, but other times will be who and what I am: different. When necessary, I will tell a person I'm Asperger's, or on the AS. Mostly because I want to contribute to educating others about autism and change stereotypic 'typing' of autistics by neurotypical people. But also to encourage them to meet us halfway.
Those are good changes.
👉For an excellent description of what the "Autism Spectrum" really is, read this webpage, "What Is Autism Spectrum Disorder (ASD)?".
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* One thing that has helped with that (all my life) is motion: pacing, twitching my leg, thumbing on a surface with my fingers, playing with my hair, bouncing on the balls of my feet, twirling my pen/pencil. Running is good; riding a horse or motorcycle is freedom. All the others mentioned were punished by my mother or teachers: slaps on the hands or knee, having to sit on my hands, told to stand still, etc. Later, it manifested in outdoor physical work and lifting weights. I wasn't hyper: it was a way of physically dealing with stress and anxiety. It 'quieted the brain and body'.