Page 107 - The autoimmune hypothesis of narcolepsy and its unexplored clinical features M.S. Schinkelshoek

other sleep disorders than narcolepsy. This may have led to a larger effect of narcolepsy in our model, that would otherwise be assigned to the presence of a SOREMP. A negative effect of selective REM-sleep deprivation on sleep state perception was shown in a study in healthy volunteers (Goulart et al., 2014), indicating a role of REM-sleep in sleep state misperception. Paradoxically, a strong positive correlation between amount of REM-sleep and perceived wakefulness in people with chronic insomnia has been described (Feige et al., 2008).
The fact that longer sleep onset latencies in nap opportunities were associated with more daytime classical sleep state misperception has been reported before in OSA patients (Bishop et al., 1998) and could also have another explanation. Due to the fact that a longer sleep onset latency unequivocally means that sleep duration during that nap was shorter, the increased sleep state misperception could therefore also be due to this shorter sleep duration. Another factor to consider is the limited duration of the nap, which restricts generalization of the relation between sleep onset latency and sleep misperception to these 20 minutes only.
A contribution of circadian factors to sleep state misperception was hypothesized in a PSG study in insomnia (Bianchi et al., 2012). In our study, we did not find a significant effect of nap timing, which argues against a role for circadian factors. Our study design did not allow for assessing the specific influence of psychiatric comorbidity, personality traits and coping mechanisms on sleep and dream perception, which were earlier described as potential determinants of sleep misperception (Fernandez-Mendoza et al., 2011). Based on the data that we had on psychiatric comorbidity, we did not see any effect on either sleep or dream perception (data not shown).
Medication and device use in our cohort was low, since most MSLTs were performed as part of the diagnostic process before medication was first prescribed. When patients using sedatives, CPAP, MAD and antidepressants were excluded from the analysis, significance of factors influencing sleep state misperception did not change (data not shown). Moreover, stimulants and sedatives were never used on the day of the MSLT. Additionally, we are not aware of any studies showing an effect of medication on sleep state misperception.
Most theories on sleep state misperception focus on the role of increased cognitive arousal and overgeneralization in people suffering from this condition (Takano et al., 2016, Maes et al., 2014, Bonnet and Arand, 1997). However, many
Daytime sleep state misperception
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