You need to find a Neuropsychologist. They often specialize in a broad area such as dementia, learning disabilities, ADHD, nonverbal learning disabilities, processing disorders, the effects of traumatic brain injury's, autism spectrum. So, in consequence, you may not see Asperger's listed as something they diagnose on a web page, etc, but you can call and confirm that it is something they do diagnose.
The cost is expensive. I was quoted by my therapist that it was between 1,500-2,000. I have an evaluation Monday, which will take 5-6 hours in itself, but is is being covered by insurance so I do not know the exact expense.
To get it covered by insurance it is necessary that you need it for adequate medical/psychiatric care, as they do not see a diagnosis as being in itself necessary under most conditions. So you must convince your insurance company that no normal therapist understands you and is capable of giving you adequate coping skills, or psychiatrist, etc.
And under no circumstance tell them you need the diagnosis to receive special accommodations at work or school, because insurance will not cover a diagnostic test for anything other that for medical reasons. This will automatically get you disqualified for a preauthorization from your insurance.
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creature1001, as explained in the Merriam-Webster's dictionary:
Swiss cheese loving neurounique alien brained human hybrid.