CNS and fibromyalgia


We know from precious research that the central nervous system is involved with fibromyalgia. It seems to be the main problem. There have been studies showing sympathetic nerves are involved with findings of damage to small nerve fiber damage in the skin, eyes and perhaps even other areas. We have a post about that actually that shows a few studies on small-fiber issues. Why are they being damaged? That is the question. Some researcher posit either a past or occurring immune disorder is to blame.

Not to mention the sympathetic nervous system and its fight or flight response is triggered by pain and has been looked at for years with FM. There seems to be involvement there as well.

So these issues with central nervous system and the skin nerve issues with FM… could they be connected? And that is where this study comes in.

The study

Marina de Tommaso, Katia Ricci, Giuseppe Libro, Eleonora Vecchio, Marianna Delussi, Anna Montemurno, Giuseppe Lopalco, and Florenzo Iannone. Pain Processing and Vegetative Dysfunction in Fibromyalgia: A Study by Sympathetic Skin Response and Laser Evoked Potentials. Pain Res Treat. 2017: 9747148.

Study included 50 patients with FM. ‘Patients with FM were recruited from the Neurophysiopathology of Pain Unit of the Bari Policlinico General Hospital from January 2015 to January 2016.’

They aimed to tackle the divide between body and brain by looking at two separate processes in the subjects. The LEP (laser-evoked potentials) test is used to see if the habitation process in the brain should dampen pain signal was working in FM. The SSR (Sympathetic skin response) test measures whether the sympathetic nerves of the skin are working as they should.

The study found: SSR (Sympathetic skin response) is delayed in fibromyalgia which suggests a problem in the skin may exist. If you look below there was a study finding that this can make a very good diagnostic tool.


Unsurprisingly, the entire group demonstrated both the slowed response of the SNS (Sympathetic nervous system) fibers in the skin AND dulled habituation processing.

‘The FM patients showed higher scores of anxiety and depression, when compared to healthy controls.’

‘No patient presented with neurological abnormalities, including distal sensory deficit.’

‘Seven patients among FM groups showed no detectable LEP response for at least one site of stimulation (5 for both hand and foot, 2 only for foot). All normal subjects showed clear LEPs responses for hand and foot stimulation’

‘The habituation index was significantly different between patients and controls at both the hand and foot sites ‘

So FM is not just a syndrome of the central nervous system but it also has an affect on the sympathetic nerves. “his study confirms the presence of SSR anomalies in a group of patients with fibromyalgia. The most evident abnormality in FM patients was the increase of SSR latency, also correlated with the increased latency of the LEP P2 component. This would suggest a common mechanism underlying these neurophysiological patterns. Furthermore, in a subgroup of patients, specifically in the 32%, the absence of at least one of the considered responses, LEPs or SSR, was observed, associated with severe disability. The reported results confirm that FM is a complex disease characterized by phenotypic heterogeneity in the functional involvement of nociceptive and vegetative systems at peripheral and central level. The following sections deal with the detailed discussion of main data.” Study

The results opened up a nice can of worms. For possibly the first time, problems with peripheral nerves in the body were correlated with central nervous system issues in fibromyalgia. Correlation is not causality, but the finding suggested that an underlying problem – still unnamed – may be producing problems in both the sympathetic and central nervous systems in fibromyalgia.

The authors pointed to a section of the brain which regulates both sympathetic and sensory stimuli processes as potentially a key factor. Immune processes are also potentially a key factor.

Plus, about a third of FM patients with more neuropathic pain and disability were different. These patients exhibited no results on one of the tests suggesting that significant nerve damage may be exacerbating or causing more pain in them.  The authors called for more studies of neuropathic pain in FM.

That small nerve fiber problems are present in FM is clear. The big question is why they’re present, what do they mean for the other issues in FM, and how to treat them? This study presents the preliminary but intriguing possibility that the issues in the brains and bodies of FM patients are connected Healthrising

Side note Additional study looking at diagnosing.

It involved 60 patients with FM and 30 in the control group who were healthy. All subjects went through lab tests, physiological tests, and sympathetic skin response SSR. They found with their ANN framework a diagnosis technique with 97.67 accuracy. Study


5 thoughts on “Central nervous system and Sympathetic Skin Response

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.