Warning: the following guidelines are not actually best practices, but more like worst practices. Proceed at your own risk.
When attending a meeting that's going on for more than 2 hours, it's acceptable to start questioning the fundamental nature of reality.
When someone asks you to summarize the last 20 minutes of the meeting, it's perfectly fine to give a 10 minute response.
And when someone asks you to take notes, it's not uncommon to just stare at them blankly while tapping your pen on the table.