REM sleep behaviour

But, in reality, it s even easier than that. For anyone to observe REM sleep behaviour directly, it can be done with bed partners, especially in the wee hours of the morning, most conveniently on vacation, in the summer time when the hillock of the cornea can be seen in the early dawn light to glide to and fro under the closed - or perhaps half-open - eyelids. The eyelids themselves dance and twitch sporadically and, when they do, one has only to give a light tap on the shoulder and ask what is going on in the mind. Informed consent is as admirable in these informal conditions as it is in university sleep labs, but don t let that stop you. 

The new kid on the dream disorder block is the REM sleep behaviour disorder (RBD), a very strange syndrome in which patients enact their dreams through movement. This is not sleep walking, although it is what sleep walking was erroneously thought to be. How does RBD come about ... 

Kunz D, Mahlberg R. A two-part, doubleblind, placebo-controlled trial of exogenous melatonin in REM sleep behaviour disorder. J Sleep Res 2010 19(4) 591-6. 

The functions of these different phases of sleep are not at all clear but chronic sleep deprivation does eventually lead to death. It seems to be the slow-wave component of sleep (SWS) that is vital and it is thought to serve a restorative purpose. This would be consistent with its greater occurrence during the early stages of the sleep cycle when hormone secretion supports anabolic metabolism. If subjects are wakened every time they enter a period of REM sleep (evidenced by the EEG) there appears to be no overt harmful effect on their behaviour. In fact, REM sleep deprivation has even been used, with some claims of success, as a treatment for minor depression. However, there is an unproven belief that REM sleep is important for memory consolidation. 

A link between 5-HT release and increased waking is supported by evidence from in vivo microdialysis of cats and rats. This has confirmed that the extracellular concentration of 5-HT in all brain regions studied to date is lower during both SWS and REM sleep than in the awake state (see Portas, Bjorvatn and Ursin 2000). Interestingly, if behaviour is maintained at a constant level, the activity of 5-HT neurons does not show circadian variation although 5-HT turnover in the brain areas to which they project... 

Increasing evidence indicates that patients with DLB experience changes in sleep behaviour and sleep architecture, both of which add to carer burden and may lead to prescription of additional medication. Sleep in DLB has not been as extensively investigated as in AD in which reductions in REM sleep (Ancoli-Israel et ah, 1994) nocturnal wandering and confusion (Ancoli-Israel et ah,... 

During TGFa infusions, episodes of waking, non-REM sleep, and REM sleep were normal in appearance, amount and duration (unpublished data). Thus the blockade of running-wheel behaviour by TGFa was not due to hypersomnolence... 

In every case, the dream report given by the patient on being awakened fits with the motor behaviour observed during the REM sleep dream. We know that these events occur in REM sleep from sleep lab evidence. 

Atonia Jouvet s great discovery, the abolition of muscle tone associated with REM sleep, is represented in my dream cataplexy. Like narcoleptics in real life, strong emotion - especially surprise - produces atonia. Perhaps I now recognize Jouvet s achievement in my behaviour. 

J. W. Kantelhardt, T. Penzel, S. Rostig, H. F. Becker, S. Havlin, and A. Bunde, Breathing during REM and non-REM sleep Correlated versus unconelated behaviour. Physica A 319, 447-457 (2003). 

We are inclined to assume that it is the slow progress of technological development that impeded scientific advances in studying dreaming. But this is a face-saving sop for those who were so conceptually blinded that they could not imagine the simple experiments that could have led to the brain activation conclusion. As Michel Jouvet shows in his novel Chateau du Reve, most of our vaunted twentieth-century discoveries about sleep could have been made earlier by the most useful scientific instrument of all direct observation. The direct observability of sleep is especially easy to achieve in our infants and children, the very individuals who most dramatically reveal the brain activation of rapid eye movement (REM) in their behaviour. 

The human newborn baby offers one of the best opportunities to observe REM behaviour directly. This is not only because REM occurs at sleep onset (as Eugene Aserinsky noticed in the young... 

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