Theories regarding RLS

No one knows the exact cause of RLS at present. Research and brain autopsies have implicated both dopaminergic system and iron insufficiency in the substantia nigra (study published in Neurology, 2003). Iron is involved in the formation of dopamine. An Icelandic study in 2005 confirmed the presence of an RLS susceptibility gene also found previously in a smaller French-Canadian population in 2003.

The continual-activation theory of restless legs syndrome proposed by Jie Zhang hypothesizes that RLS occurs when a brain mechanism which is evolved for safeguard brain from "brain death" during sleep, is wrongly turned on during waking time. The theory is developed through a series of hypotheses.

Zhang believes that human brain can be divided into two subsidiary systems: the conscious brain and the non-conscious brain. The conscious subsidiary system of brain is evolved to process conscious related human information like declarative memory for instance, while the non-conscious subsidiary system is evolved to process non-conscious related information such as procedural memory and motor skills. In order to maintain brain proper functioning, Zhang proposes that both systems have to be continually activated through their life times. To carry out this task, Zhang suggests that human brain has a continual-activation mechanism in each subsidiary system. When the level of activation in any subsidiary system descends to a given threshold, the corresponding continual-activation mechanism will be triggered to generate a pulse-like activation signal. According to this theory, the continual-activation mechanism in the non-conscious part of brain is supposed to be turned on during NREM sleep; while the continual-activation mechanism in the conscious part of brain is supposed to be switched on during REM sleep.

RLS occurs when the continual-activation mechanism in the non-conscious subsidiary system of brain is wrongly triggered during waking, due to the malfunction of continual-activation thresholds. The theory also predicts that a close related illness - PLMD (periodic limb movement disorder) is sprung from the same mechanism, but with different cause. PLMD occurs when the lowered muscle tone is lacking while this mechanism is activated during NREM sleep. (Zhang, 2005a & 2005b).

	Does RLS keeps you awake at night? Talk to your doctor about sleeping disorder and restless legs syndrome at your earliest convenience.