I know it's a little late in the month, but I do Not see nearly enough people talk about or advocate for PDA autism- most people here in the US (don't know about other countries) haven't even heard of it. So, since it's disability pride month, and autism is a disability...
PDA autism (or just. PDA) is an autism profile with a particular focus on the sense of justice bit. PDA stands for pathological demand avoidance, because people with this profile will go into fight or flight mode when they feel a demand on them- what exactly qualifies as a demand will vary from person to person, for me I don't mind demands that seem completely reasonable, like a director for a play I'm in asking me to do something with my acting.
We also have trouble with the idea of authority- well that's how it's described, though imo that's a littleee misleading. I usually explain the feeling as "why does this guy think they're better than me or that their opinion is magically more important just because they're older than me". Oftentimes I don't mind "authority figures" as long as they don't act like they're all superior.
People with PDA also have a limited amount of demands they can handle in a day, well phrased/reasonable or not- I call it my "demand tank". Its a lot like spoons. If there's too many demands, it gets way harder to do anything or to be nice to people, and this can be long-term as well as short-term. If you have a week of high demands, even if no single day emptied your tank, you might feel emptied by the end of the week.
We tend to have a hard time just accepting when things are unfair or imperfect in a way other people seem not to. A lot of people will just sort of shrug and accept that some things suck or this particular thing just isn't fair, but we tend to get seriously upset.
Lastly, and in my opinion this is one of the most important things to understand about PDA, is that our emotions don't just go away over time. A good way I've seen it described that I use in my own life is to imagine a bucket. in non-PDAer's, the bucket has a small hole or a few small holes in the bottom that let the emotions slowly drain out on their own. They'll drain faster if the bucket is tipped over, and can still overflow if the bucket is being filled quickly enough, but most people won't say, still be mad about an argument from a week ago; the emotions drained out. Conversely, people with PDA do not have any holes in the bottom of the bucket, We NEED to tip our buckets to get the emotions out or they just sit there. I don't ever just get over stuff.
How can I help my friends/family/children/students who have PDA?
The most important thing is understanding. My personal experience is that being understood makes me feel better than anything else; even if I get exactly what I want, if the people around me don't understand why I wanted it, it doesn't make a difference.
If you need to ask a PDAer to do something, ask, don't command. Begin with "can you" and end with "please" (well, the please is less important). It might seem obvious, and that everyone wants that, but a lot of people don't do this, and a lot of other people seem fine with that. You also need to be ready to accept if we can't/won't do it- I'm usually happy to help if the request is phrased as such, but sometimes things happen, and I'll usually explain why. This second part is also important, because my experience has been that I care much more about people's underlying intent than their actual words, so if you intend to make me do something, using the words "can you" is no good.
Reducing other demands that aren't necessary is also seriously helpful. Does that kid REALLY need to sit still? Do they REALLY need to be quiet? Genuinely consider what is and is not necessary; the wholly unnecessary demands are much more upsetting because they double as an unfair situation.
Sometimes PDAers need to have a "bucket spill"- I'll just randomly start having a mild meltdown for no apparent reason. I just need to empty out the negative emotions from the week/day/whatever.
For me, being thanked for things I wasn't asked to do feels passive aggressive- a lot of things feel passive aggressive, actually. It feels like an assertion that I did something I was expected to do but wasn't told to do. It feels like retroactively turning something that wasn't a demand into one, and therefore making me having done something I was demanded to do.
How do I know if I have PDA?
The most noticeable thing is that anything you attempt to do something someone else is trying to get you to do, it feels like your nervous system is trying to kill you :). That's hyperbole of course, but if you feel an intense negative reaction at the idea of doing something you were told/expected/wanted to do, that's obviously a top sign.
If you struggle to move on from obviously terrible things that other people seem to just not care about, that's also a sign- not to say caring about injustices is a disorder, but if it seriously negatively affects you and you feel like you cannot move on until it's fixed, that's a sign.
If you sometimes won't eat, drink, brush your teeth, shower, take deep breaths to calm down, etc. etc. because it feels like other people expect/want you to, that's also a strong sign.
There's others, but these are a good place to start; if you can find a list of symptoms, it shouldn't be toooo hard to check yourself against that. It's important to note that PDA does not even exist as a diagnosis in the USA, self diagnosis is the Only Option for PDAers that live here. I personally hit every symptom on the list, but that won't be true of all of us.