Oh, I forgot, you'll have a video camera on the wall on all night to play back so that they can watch your face and your limbs, how often you toss and turn, etc. Any physical movement is part of an arousal response, any restriction of flow into your lungs based on what you need, or your 'demand', at the time (called an RERA (respiration effort related arousal) will be detected and checked for timeline. Once that is all coordinated, the record will clearly show what you did, how you reacted, and also the brain activity at the time. If done properly, a polysomnography is a very comprehensive and accurate diagnostic for your disordered sleep or your disordered breathing.
Also, if it turns out you need treatment, even for mild apnea, please consider going over to apneaboard.com forums and taking a look. There are some very knowledgeable gurus there who can help you to get the most out of your CPAP machine...IF...you end up with one out of necessity. Some need a lot of hand-holding until they finally get their prescription dialed-in enough that it works for them. The goal is not the hand-holding, it's getting the PAP machine to do what you need it to do for a restful sleep with very few arousals.