Which preposition to use with uncommunicative

about Occurrences 1%

He was more than usually uncommunicative about his house-party experiences the Doctor thought and fancied too that just at first after his return the boy did not meet his eyes quite frankly.

as Occurrences 1%

There is nothing in this world quite so stolid and uncommunicative as a boy who has made up his mind to be stolid and uncommunicative; and the headmaster, as he sat and looked at Mike, who sat and looked past him at the bookshelves, felt awkward.

Which preposition to use with  uncommunicative