The potential beneficial effect of sleep deprivation following traumatic events to preventing PTSD: Review of current insight regarding sleep, memory, and trauma resonating with ancient rituals—Àìsùn Oku (African) and Tsuya (Japanese)

Abstract

Sleep figures in numerous ancient texts, for example, Epic of Gilgamesh, and has been a focus for countless mystical and philosophical texts. Even in the present century, sleep remains one of the most complex behaviors whose function still remains to be further explored. Current hypotheses suggest that among other functions, sleep contributes to memory processes. Memory is a core topic of study in post-traumatic stress disorder (PTSD) and other stress-related phenomena. It is widely accepted that sleep plays a major role in the consolidation of newly encoded hippocampusdependent memories to pre-existing knowledge networks. Conversely, sleep deprivation disrupts consolidation and impairs memory retrieval. Along this line, sleep deprivation following a potentially traumatic event may interfere with the consolidation of event-related memories and, thereby, may reduce long-term post-traumatic stress-related symptoms. This review consolidates clinical and animal studies on the relationships between sleep, sleep deprivation, memory processes, and trauma exposure while introducing new contemporary insights into an ancient African tribal ritual (Àìsùn Oku) and Japanese ceremony ritual (Tsuya). We propose that these findings, focusing specifically on the effects of sleep deprivation in the immediate aftermath of traumatic events, may be explored as a possible therapeutic measure. Along with a summary of the field questions on whether sleep is performed "to remember" or "to forget" we lay the rationale for using sleep deprivation as a clinical tool. A tool that may partially prevent the long-term persistence of these traumatic events' memory and thereby, at least partly, attenuating the development of PTSD.

Acute sleep deprivation reduces fear memories in male and female mice

“…A novel and distinguishing feature of these studies is that the sleep deprivation was performed on the day after fear conditioning, following an 18-hr period when the mice were left undisturbed and thus able to sleep normally. While there have been other reports that sleep deprivation can disrupt fear behaviors, in general those have demonstrated that it is necessary to perform the sleep deprivation immediately, beginning within the minutes after fear conditioning 6,7 . The effects were qualitatively and quantitatively similar in similar in males and females, suggesting that they involve mechanisms that are similar across sexes.…”

“…The ability to sleep after experiencing a traumatic event (e.g., an assault, accident, combat mission, mass casualty incident) is often compromised due to various situational parameters, such as the need for medical or police intervention, the need to remain on duty, or subsequent trauma-related insomnia. Interestingly, there are reports that sleep deprivation immediately after a traumatic experience can reduce fear memories, an effect that could be utilized therapeutically in humans 6,7 . Despite its potential importance, however, the role of sleep in the development of and/or recovery from trauma-related illnesses is not fully understood.…”