Neurocousin

Another development during the 1993 conference was the recognition of a new segment of the ANI community, and the adoption of a new term to refer to it. One of the people who had been corresponding with ANI members online, and was attending this conference to meet with us in person for the first time, was not autistic. He had hydrocephalus, another congenital neurological abnormality. In our online discussions he had been noticing many similarities between his experiences and characteristics as a person with hydrocephalus, and the experiences and characteristics of autistic people. At the conference he met Kathy, who was not online at the time and did not know who he was. He introduced himself to her, explaining that he was interested in exploring similarities between himself and autistic people. He briefly summarized the effects of hydrocephalus in his life. Kathy considered this for a moment, and then warmly exclaimed “Cousin!” (Cousins, 1993). From that time on, the term “cousin” has been used within ANI to refer to a non-autistic person who has some other significant social and communication abnormalities that render him or her significantly “autistic-like.” The broader term “AC,” meaning “autistics and cousins,” emerged soon afterward.
History of ANI

There’s something the autistic community⁠ has lost. And I think it’s high time we got it back, possibly in an improved form. It’s the concept of cousins.

I can remember when ‘cousin’ was a well-known term and used widely, even outside of ANI-related circles. And then, gradually, its use died out and a lot of people seemed to forget — or not know in the first place — it had ever existed.

I only ever saw one criticism of ‘cousin’ that made sense to me. And that was more about the way people used the idea, rather than the idea itself. This was, that people used ‘cousin’ in a way that made it sound like autism was the one central way to be neurodivergent, and everything else was judged by whether it was similar to autism or not.

If the ‘cousin’ idea is brought back, I hope that it won’t be seen as exclusive to autism. It can be used for practically any form of neurodivergence or similar experience of the world.
Mel Baggs, Reviving the concept of cousins. | Ballastexistenz

Bringing people together with words like ‘cousin’ allows people to identify with autistic people, without putting pressure on them to figure out instantly whether they are actually autistic or not. It allows people to acknowledge that most skills and difficulties autistic people experience are not totally unique to autistic people. It allows people to acknowledge the vast grey area that is both outside of standard definitions of autism, and outside of neurotypical, but that resembles autism in important ways. It allows people to acknowledge that the boundary between autistic and nonautistic is fuzzy at best. And it does all that while contributing to people understanding more about themselves and each other, and bringing people together into friendships, communities, and other relationships they might not otherwise have.

So I really believe that it would not only be a good thing to remember the word ‘cousin’ and what it used to mean, but to revive it and expand its use for more than just autistic people. It allows for so much more flexibility than people are currently given about a lot of different identity groups, and that’s important. So if you like the idea of cousins, by all means, use it and adapt it as much as you want, for whatever groups of people in your own life you think it would best apply to.
Mel Baggs, Reviving the concept of cousins. | Ballastexistenz

Cousin refers to a person who is not NT, is not quite autistic, but is recognizably “autistic-like” particularly in terms of communication and social characteristics. Some conditions that may lead to cousinhood include Tourette syndrome, hydrocephalus, Williams syndrome, and some learning disabilities.

AC stands for “autistic and/or cousin.” “AC” and “cousin” are sociological terms describing status within the ANI community, rather than clinical diagnostic terms.
Jim Sinclair, Language and abbreviations