Comments by "SmallSpoonBrigade" (@SmallSpoonBrigade) on "Attention Deficit Hyperactivity Disorder vs Autism – How To Tell The Difference" video.

That's the Schizoid Personality. It's effectively a person within a person that doesn't ever interact directly with the outside world. It's something that people doing these diagnoses should be on the lookout for as it requires a lot more work to get to the bottom of what's going on, even if you've got somebody coming in that wants a correct diagnosis.
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Professionals are trained to see ASD symptoms in intellectually disabled white boys under a certain age. Anybody else is likely to have problems getting a proper diagnosis. I've personally been going the route of collecting every single misdiagnosis for ASD possible, and they still don't want to admit that it might just be ASD. I've been diagnosed and/or treated for Schizoaffective Disorder, Schizotypal Personality Disorder, Schizoid Personalitly Disorder, Major Depressive Disorder, Bipolar 1, Generalized Anxiety Disorder, Somatacization Disorder, OCD, ADHD and I'm probably forgetting something in that list. I think the only ones I haven't yet been diagnosed with are Borderline Personality Disorder and PTSD. At this point, I'm kind of stuck pushing for an ASD diagnosis as that list is bad enough that getting decent medical care can be an issue as so much of what I deal with medically isn't taken seriously as with all that comes a bunch of psychosomatic disorders like idiopathic tinnitus, IBS and migraines.
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I wish they'd stop calling ASD a spectrum disorder. It's not a spectrum disorder, a spectrum disorder would be something like the schizophrenia spectrum disorders where there are different diagnoses within it that are at least somewhat helpful when presented with a diagnosis. ASD only has the Spectrum in it because there were a clustering of diagnoses that were obliterated to give a single diagnosis, but it inexplicably, and confusingly, leaves out ADHD and Schizoid Personality Disorder which are both in all likelihood also forms of autism. It also doesn't include Social Pragmatic Communication Disorder as well, meaning that there are more non-ASD autism diagnoses than ones that are "within the spectrum." (The non-autistic Schizoids largely don't get that diagnosis these days as Schizotypal Personality Disorder and Avoidant Personality disorder got most of them to the point where the diagnosis is mostly inactive at this stage) Yes, there are a wide range of specific traits and experiences, but that's mostly because of just how sloppy the diagnostic criteria are. There is no provision at all for folks with a more internalized presentation of the disorder. Which does make some sense as brain scan technologies have come a long way and it was just assumed that the developmental process gets close enough sooner than it really does.
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