See, that I've been trying to get a clear understanding of, too. (Which is why I need resources!! !!) With what little I found, it sounds like it's the societal privileges that people get just because they're neurotypical, which exceeds those of neurodiverse groups. It's not something people realize that they have. I think an example could be that I, as a mostly NT, can go out in public and not have people stare at me (for overt stimming, etc...people find lots of reasons to stare). No one treats me like a child or tries to cure me or anything like that. That's my general understanding, and it does seem like something that actually very much exists. (Although others may prefer a different label?) I think that basically if you take the idea of white privilege and replace white with neurotypical and color with neurodiverse, you'd get the general idea:
"White privilege (or white skin privilege) refers to the set of societal privileges that white people are argued to benefit from beyond those commonly experienced by people of color in the same social, political, or economic spaces (nation, community, workplace, income, etc.).[note 1] The term denotes both obvious and less obvious unspoken advantages that white individuals may not recognize they have, which distinguishes it from overt bias or prejudice.[1] These include cultural affirmations of one's own worth; greater presumed social status; and freedom to move, buy, work, play, and speak freely.[2] The concept of white privilege also implies the right to assume the universality of one's own experiences, marking others as different or exceptional while perceiving oneself as normal."
I'm not a scholar in this area or anything - just read a blog post and it kind of seemed like it had some very good points and I want some more resources, not only for myself, but also for others (once I verify this).
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I'm BAP and a big sister to an Autistic woman. We made some websites to help kids on the spectrum and parents understand autism in a positive way:
http://www.teachmeaboutautism.com/