In residency, we got a patient who had an aneurysm burst with several interventions. When she came in, speech therapy evaluated her and said that her "cognitive-linguistic skills are normal." Now I may not have the same level of expertise and sophisticated testing as a speech therapist, but I am pretty sure that adults with normal cognition don't sign their names like this:
(Not her actual signature, but my reproduction of it.)
They also don't try to grab your notes from you as you're talking to them. Or think you disappeared when you stand on their left side. Or put their feet up on the neuropsychologist's desk as they're being tested.