Restless legs syndrome, painful and tiring for people who suffer from this pathology, is linked to the modification of the somatosensory cortex, the part of the brain that processes sensory information.
- 2 to 8% of French people suffer from restless legs syndrome.
- The main symptoms of restless legs syndrome are tingling, itching, tingling or muscle contractures.
An irrepressible need to get up, tingling and itching in the legs, especially at night, which greatly degrade the quality of sleep. These painful symptoms are part of the daily life of 2 to 8% of French people. They suffer from Willis-Ekbom disease, also known as restless leg syndrome. In some cases, exercise can alleviate symptoms. Iron supplements may also be necessary in the event of a deficiency of this mineral. There are also drugs for the most severely affected patients, but many have serious side effects if taken too long.
Until now, a lack of dopamine, a chemical that allows information to be transmitted between nerve cells in the spinal cord, has been associated with restless legs syndrome; but the latter would also be linked to a dysfunction of the part of the brain that processes sensory information. This is the explanation presented by researchers from the University of Minnesota, whose study was published in Neurology, the medical journal of the American Academy of Neurology.
“Our study – the first to show changes in the sensory system with restless leg syndrome, we believe – found structural changes in the brain’s somatosensory cortex, the area that processes sensations,” said said Byeong-Yeul Lee, lead author of the study.
The somatosensory cortex of the brain is part of the body’s somatosensory system: it receives information from the surface of the body through relay neurons and sensory neurons. This system helps us to perceive touch, temperature, pain, movement and position. For the researchers, “these symptoms are most likely related to pathological changes in this area of the brain”.
Changes in the somatosensory cortex
The study involved 28 people suffering from the syndrome for an average of 13 years, and victims of severe symptoms. They were compared with 51 other participants who were not affected by restless legs syndrome. Each of them underwent a brain scan with magnetic resonance imaging (MRI).
The researchers found that people with restless legs syndrome had a 7.5% reduction in the average thickness of brain tissue in the somatosensory cortex compared to control participants. They were also able to notice that the area of the brain where nerve fibers connect one side of the brain to the other was significantly reduced.
“These structural changes tend to provide evidence that the symptoms of restless legs syndrome stem from unique changes in the brain, and reveal a new area to explore to understand the syndrome and potentially develop new treatments.”
Research suggests a possible link between symptoms and regions of the brain that process sensory information, so restless leg syndrome could be linked to impaired function in other parts of the sensory system. However, other studies will have to demonstrate this.