from my understanding a control question is more vague and less direct then a relevant question. Something that can have multi answers such as “Did you ever steal something?” rather than something more the lines of “Did you steal that cookie?” would be a relevant question. And I may stand corrected but you want to respond stronger to the control questions and slightly less to the relevant ones.

FoxxyV

Holding your breath for 5-9 seconds is a strong signal to the polygrapher that you are trying to beat the machine. He will probably stop the test and ask you what you are trying to do. You are expected to breath so many times a minute.

I don't think the anal squeeze is detectable beyond a guess. In my research, I found that mental countermeasures work better and are certainly NOT detectable. For instance: I have had encounters with old grizzly bear, in the wilderness, and I'm scared as hell of them. Therefore, in research tests, I picture him charging and the needle spikes. On relivant questions, I picture myself setting on the banks of a stream reading a good book or taking in the scenery and I can almost make the needles straight line.