First, many psychologists who do adult assessment do not focus on autism—and their reference for what autism is maybe based on severe and more stereotypical cases, which have been identified early in childhood due to severe needs. Though it would be incredibly rare to find a psychologist who “didn’t assess” for conditions like ADHD or mood disorders like anxiety and depression, many psychologists do not get the training on more complex or subtle presentations of autism and simply do not address it. This is a significant problem, since an individual could be assessed by a psychologist like this and the issue of autism would not be examined or in many cases, even brought up to the family.
Adults who are wondering about an autism diagnosis and seeking an evaluation for the first time have often learned many “tricks” to get by socially, which is often described by “masking” or “camouflaging” symptoms. Many of these individuals may have people-watched or watched television shows in attempts to learn how to be successful socially, to the point where many of the “autistic” symptoms are less visible or obvious.