I can read general body language, but I can't detect another person with AS or ADHD. I can sometimes figure out that there may be something a little bit different from the general norm, but I can't always pinpoint what it exactly is. Reading body language doesn't always mean you can immediately define their neurological condition exactly, unless they are more severe and so show obvious symptoms like hand flapping, etc.
However, I can often tell if somebody's the sort of person that gets anxious or nervous a lot. Also I can try to gather the information of somebody's slightly different behaviour and try to fit it together to see if it could be an ASD, but even then you can't always be certain, especially if they are mild enough to be able to hide it and pass off as NT (like me). I know an older woman who I often wonder if she has AS. Although she is a very chatty person and is good with dealing with the public, I can tell that a lot of it is forced, as though she's spent most of her life really trying hard to learn these skills. I've seen her stretch her fingers then screw her hands up tight repetitively when she's in an awkward situation, as though it is a little stim what she does. Also one of her co-workers told me that he can't always figure out what she's feeling, she has this blank expression on her face a lot, especially when she's anxious, and she just acts rude to you and makes you unsure if she doesn't want you there or if she's just stressed. But, again, all that doesn't necessarily indicate an ASD. It could be from anything, from a stress disorder, to PTSD.
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Female