Official Publication of the Sleep Research Society - Oxford Academic ... assessed with a word list test at 1, 2, 4, 6, 8, 10 and 12 hours after the ... Atrooz F, Salim S. University of ... When people were sleep loss, PVT RT is slowly increased from. 0:00 to ... (2000, 2100 EST) - upswing of circadian-regulated alertness ?com- ... only participants who (a) rated their happiness between 8PM-?2AM, (b).