Die Muttersprache vergisst man nicht - or do you? A case study in L1 attrition and its (partial) reversal.

Is it possible to undo or reverse language attrition? In other words, has there been, in the case of attrition, a permanent change with respect to the speaker's L1 knowledge, or do we only see temporary effects on the control of that knowledge? It is proposed here that the concept of attrition should include the temporary loss of language skills since it is, so far, not clear whether or to what ex…