Jung suffered another embolism, diagnosed as a blood clot that traveled to his brain , caused a stroke, and affected his speech. Some of his grandchildren were reduced to tears by the sight of the once-powerful head of their household now himself reduced to tears because he new that gibberish , not speech, was pouring from his mouth. If he did manage words, they were a melange of all the languages he knew, plus an incomprehensible Schwizertütsch, but not in any order that made sense. They believed that nothing in Jung’s long life distressed him as much as this inability to communicate through language.
Source:
Deirdre Bair, Jung, a Biography