Paradoxical switching to a barely-mastered second language by an aphasic patient

Polyglot speakers who become aphasics are not necessarily affected to the same extent in each language. In some cases there is a mixing of the different languages or a switching between languages and in very rare cases the switch is to the language seldom if ever used in everyday live. We report a French-speaking aphasic, who switched paradoxically from his mother tongue (French) to a second language (German) which he had learned at school but barely mastered and hardly ever spoke, and kept using German most of the time. We tried to understand the mechanism responsible for that phenomenon by reviewing the actual hypothesis of multi-language organization. We concluded, in line with previous reports, that our case used his metalinguistic knowledge to compensate for his inability to access his linguistic skills.