If you go to the site's "Welcome" page and look on the right hand side, there are links for various "functional" disorders, including:
Poor memory / Concentration (7 links down in first column)
This link opens page:
Functional Memory and Concentration symptoms
The disorders described on the patient resource site are termed "Functional symptoms" or "Functional disorders" because no recognized neurological disorder can be found on examination or where there is positive evidence of inconsistency or incongruity with known neurological disorders.
That is, they are considered to be due to a problem with the functioning of the nervous system and not due to neurological disease.
These disorders were known as "Conversion disorders" or "Dissociative disorders" but the term "Functional neurological symptom disorders" is now often used to describe them.
I'm sorry I don't have anything useful to say re conversion disorder, but just wanted to say hello again - and I'm sorry that you are still obviously having problems re diagnosis of your husband's problems.
I hope that you are holding up with it all after all this time and coping yourself x