Despite the advantages of sleep during subjective latency (SDSL) as a phenotyping tool to overcome operational issues with quantifying misperception, the results of a recent study argue against the hypothesis that light or fragmented sleep underlies misperception. Researchers performed a retrospective analysis on patients with or without obstructive sleep apnea (OSA) during overnight diagnostic polysomnography (n=391; n=252). They compared subjective and objective sleep-wake durations to characterize misperception, introducing SDSL, which captures latency misperception without defining objective sleep latency. It also allows correction for latency misperception when assessing total sleep time (TST) misperception. They found:

• Those with >20 minutes of SDSL had less N1%, more N3%, and lower transition frequency.

• After adjusting for misperceived sleep during subjective sleep latency, TST misperception was greater in those with longer bouts of rapid eye movement (REM) and N2 stages (OSA patients) as well as N3 (non-OSA patients).

Citation: Saline A, Goparaju B, Bianchi MT. Sleep fragmentation does not explain misperception of latency or total sleep time. [Published online ahead of print May 25, 2016]. J Clin Sleep Med. pii:jc-00506-15.