Re: diametric models of autism and schizophrenia, I recently read a couple of posts by Vaticidalprophet on Substack which I found fairly convincing on the matter: https://vaticidalprophet.substack.com/p/williams-syndrome-syndromic-autism makes the case that the diametrical model relies on adjusting definitions when they contradict the evidence, and https://vaticidalprophet.substack.com/p/disorganized-schizotypy-and-the-problem, though mostly a critique of diagnostic measures for schizotypy, also makes the IMO decisive-if-true argument that autism and schizophrenia are positively correlated. (I’ve copied out the paragraph with most of his citations below for easier reference.)
Populations that are not neurotypical undergrads in Western Canada tend to, uh, not demonstrate this (see Dinsdale et al., 2013 — on which Crespi was corresponding author — for a very teeth-gritted literature review in the intro). Even in other undergrad populations Crespi’s anticorrelation is doubtful, particularly on non-SPQ instruments (Russell-Smith et al., 2011 is Dinsdale’s cite, but I’ve seen quite a few variants of this). Amongst people actually diagnosed with autism or schizotypal personality disorder, who seem like, you know, useful populations to study this in, there seems to be a there there (Barneveld et al., 2011; Esterberg et al., 2008). Outright psychosis definitely has a there there (Kiyono et al., 2020), and you keep running into hilarious studies that claim gold-standard ASD diagnostic instruments don’t work because they “misdiagnose” 30% of schizophrenics with autism (Maddox et al., 2017).5 Funniest of all, internet surveys find a large schizo-autistic population (Ford et al., 2018).
Re: diametric models of autism and schizophrenia, I recently read a couple of posts by Vaticidalprophet on Substack which I found fairly convincing on the matter: https://vaticidalprophet.substack.com/p/williams-syndrome-syndromic-autism makes the case that the diametrical model relies on adjusting definitions when they contradict the evidence, and https://vaticidalprophet.substack.com/p/disorganized-schizotypy-and-the-problem, though mostly a critique of diagnostic measures for schizotypy, also makes the IMO decisive-if-true argument that autism and schizophrenia are positively correlated. (I’ve copied out the paragraph with most of his citations below for easier reference.)