A Full PSG (Polysomngraphy) is the most complete form of Sleep Testing.
This usually requires at least 1 night stay in the hospital. A sleep technologist will place electrode sensors to monitor your brain activity, oxygen level, eye and limb movements, muscle tone, and heart rate. Nasal cannula and belts will be placed to measure your respiratory effort. If the recordings detect effort in breathing but no airflow, you are suffering from OSA. However, if there is no effort in breathing and no airflow, you could be having Central Sleep Apnea. The signals are transmitted to a computer and finally the results are either scored by the sleep technologist or a sleep physician.
A full PSG study can detect other forms of sleep disorders such as insomnia, periodic leg movement syndrome. The electrodes can record up to 60 channels of recording such as EEG, EOG, EKG,EMG.