I came across this research article which says that Golden (Syrian) Hamsters in captivity are nocturnal - it is only in the wild they are diurnal or awake at times other than night time. To do with less of a threat from predators changing their circadium rhythms apparently. Might explain why some Syrians don't come out much!
https://www.ncbi.nlm.nih.gov/pmc/art...2610053/#bib16