Automated sleep staging systems in rats.

One of the major inconveniences encountered in sleep studies is the time consuming labor involved in equating visual analysis of physiological recordings (EEG, EMG, EOG, ...) to an appropriate state of vigilance. The explosion of computer technology is responsible for the emergence of several automated sleep-wake staging systems to supplement human analysis. Conversely to human sleep analysis, rat sleep is characterized by the absence of consensus about numerous elements constituting the sleep-wake staging systems used to build a hypnogram (recording position, length of epoch, number and definition of the vigilance state discriminated, ...). If justified, the choices of the parameters involved by each system generally result from various viewpoints (physiology, mathematics, electronics, ...). The diversity generated by the liberty offered the investigator in building a system excludes any rigorous comparison between systems. Nevertheless, this variety can also be viewed as a representative of the effervescence of research in the field of sleep, and as a catalyst for new ideas.