Sleep characterization of a one-month-old freely moving stumptail macaque (Macaca arctoides): a pilot study.

Electroencephalographic (EEG) activity during both human and adult primates' sleep has been proven to be similar and consequently, it could be assessed under similar parameters. However, there is no information regarding this EEG activity in the early stages of development in non-human primates. Therefore, the aim of this study was to describe EEG sleep patterns in a 1-month-old Macaca arctoides with a non-invasive and free-movement method. Sleep stages were initially scored using the criteria of quiet sleep and active sleep. This procedure allowed us to observe graphoelements to distinguish sleep phases as described in adult macaques. Afterwards, the final score was recorded following the Slow Wave Sleep and Rapid Eye Movement Sleep criteria. The present results suggest that sleep features of this monkey are similar to those of a 2-month-old human neonate.