A mains electricity (AC-powered) device designed to record and interpret a variety of physiologic functions during sleep to evaluate sleep/sleep-related disorders (e.g., insomnia, hypersomnia, apnoea). It typically performs electroencephalography, electrocardiography, electro-oculography, electromyography, and respiration, temperature, and pulse oximetry readings. It may also provide audiovisual information about the sleeping patient for behavioral analysis and other measurements (e.g., gastric reflux, bedwetting). The device includes electrodes, measuring instruments, samplers, filters, amplifiers, and appropriate software for processing data and providing patient diagnoses.