When faced with a question they cannot answer, a person enters a shutdown state.
This is also a form of self-protection, or "defense."
Those interested can search for videos of college students' graduation thesis defenses, where many students, upon encountering unexpected questions from the teachers, reveal a clear smile.
— You might think they're trying to play cute to pass or brace for criticism; but in fact, their brain's CPU has simply crashed, and while they appear to be present, they've actually checked out a while ago.
But this state isn't exactly a "crash," as the human brain still receives external information.
If at this moment, the questioner asks another question or mentions something within the respondent's knowledge area,
the respondent will quickly reboot and start acting; the purpose is simply to escape the awkward situation.
