I applaud your doing the research on various labels and categories in the topic of aphasia. It can be quite convoluted and complicated. While there is a general consensus on the descriptions in the types of aphasia, there is also variability even within these groups.

I am not very clear from your description about the nature of the person’s speech and language. Even with a fairly lengthy description, I would feel uncomfortable trying to give an exact label or diagnosis without seeing and evaluating the person. Has the person you described been evaluated by several types of medical professionals, including a speech-language pathologist? I am thinking that evaluations by neurology, neuropsychology and speech-language pathology might be appropriate.
Anne

Due to financial considerations, I think it’s better to find out what it’s called beforehand instead of creating a mounting debt by trying to see a series of specialists who may or not have the appropriate expertise, which is why I asked in the first place.

When this person first started to wander in and out of these episodes, they got a relatively full checkup (but no NMRI) and nothing was found. A psychiatrist was clueless about it after a series of tests and sessions, except to suggest that it might be a form of benign schizophrenia … which by definition schizophrenia isn’t.

He can understand normal speech, but responds with these random strings which he thinks are quite rational until he drops back into “normal” speech and is told what he said. It’s that responsiveness which eliminated Turrette’s as a possibility, and made me look into aphasia.