Posted by zeugma on March 30, 2006, at 21:13:30
In reply to Re: melatonin, REM, Parkinson's disease, posted by Cairo on March 30, 2006, at 19:41:10
It has been known for a long time that antidepressants tend to lower the seizure threshold, and to suppress REM sleep; and that antiepileptic compunds can control manic episodes, and suppress NREM sleep. So the simplistic deduction, akin to that of the monoamine theorists of the 1960's, is that depressives have too much REM and manics not enough. This is not very satisfying, because it explains nothing. What is the purpose of REM anyway?
i find this theory intriguing (I lack the knowledge to assess its plausibility, but it at least explains what REM is for, even if the explanation is spurious [I am having trouble writing now]:
Med Hypotheses. 2004;62(4):546-8.
Purpose of REM sleep: endogenous anti-epileptogenesis in man -- a hypothesis.Jaseja H.
Physiology department, G.R. Medical College, Gwalior, MP 474001, India. dr_jaseja@yahoo.com
Neuro-scientists, worldwide, are endeavoring to elucidate the purpose of sleep which still remains largely elusive. There is, however, consensus on many aspects of sleep functions; one such aspect is its relationship with seizures/epilepsy. There is unequivocal agreement on increased susceptibility to epilepsy during nonrapid eye movement (NREM, slow-wave) sleep. Large number of studies have shown increased frequency of seizures and interictal epileptiform discharges in epileptic patients during NREM sleep (esp., stages I and II) which is associated with EEG synchronization. Similarly, there is widespread acceptance of de-synchronized brain-activity states being associated with rarity/total absence of epileptic potentials, one such state being rapid eye movement (REM) sleep. Certain drugs and substances which inhibit NREM sleep have been found to possess anti-convulsant properties. Not surprisingly, drugs/chemicals which enhance/promote NREM sleep or suppress/inhibit REM sleep are associated with increased susceptibility to seizures and are contraindicated in epilepsy. The manner and pattern in which REM phase occurs in sleep are also naturally programmed to exert anti-epileptogenic influence. This hypothesis-article highlights and conceptualizes the primary function of REM-sleep as endogenous anti-epileptogenic system in the body akin to the endogenous analgesia and immune systems man is born with.
>>>>>>>>>>>>>>>>>
So, if this author is on the right track, perhaps manics have a breakdown of the anti-epileptigenic system, and depressives a pathologically powerful system (perhaps perversely parallel to an individual with hypoalgesia, who soon becomes riddled with wounds he cannot feel).
I am just thinking out loud, and I do not know enough to theorize. It really just seems suggestive to me, and I have never heard of the body possessing a system devoted to suppressing seizures. It seems everyone got tired of vague metaphors about mania being a 'slow seizure,' and it seems the REM hypothesis of depression made its exit with fluoxetine, and maybe the theory led nowhere in particular.
But everyone can readily accept, on a commonsense level, the existence of analgesic and immune systems (we are all too prone to pain and infection). Is it plausible that we are also seizure-prone enough to have such a delicate system for averting them?
-z
poster:zeugma
thread:626219
URL: http://www.dr-bob.org/babble/20060329/msgs/626866.html