- Study at Stanford University examined MRI scans of CFS patients comparing them to those of healthy volunteers
- Found three distinct differences in different parts of the brain
- CFS patients found to have lower levels of white matter - which carries information and signals between different parts of the brain
- A tract connecting the frontal and temporal lobes was found to be abnormal
- And grey matter - which processes information - in those two areas of the brain was thicker in CFS patients
- Hopes the discovery will lead to better diagnosis and treatment of condition
- Adds weight to debate over legitimacy of the condition, which is constantly questioned and mistaken as being hypochondria
The brains of those diagnosed with chronic fatigue syndrome are distinctly different to those of healthy people, scientists have discovered.
The study promises to add weight to the debate over the legitimacy of the condition, which is repeatedly called into question.
A team of researchers at Stanford University School of Medicine believe their findings could lead to more definitive diagnoses of the syndrome and better treatments.
And it is thought the study could help point to an underlying mechanism governing the disease.
It is not uncommon for CFS patients to face misunderstanding of their condition, plagued by suspicions of hypochondria.
But the abnormalities identified in this study, published in the journal Radiology, will, it is hoped, go some way to helping resolve those ambiguities.
Lead author Michael Zeineh, assistant professor of radiology, said: 'This is a very common and debilitating disease.
'It's very frustrating for patients, because they feel tired and are experiencing difficulty thinking, and the science has yet to determine what has gone wrong.
'Using a trio of sophisticated imaging methodologies, we found that CFS patients' brains diverge from those of healthy subjects in at least three distinct ways.'
The condition affects between one and four million in the US and millions more worldwide.
Putting a definitive figure on the number of sufferers is difficult, because CFS can be difficult to diagnose.
While all patients share a common symptom - crushing, unremitting fatigue that persists for six months or longer - additional symptoms can vary from one patient to the next, often overlapping with other conditions.
Professor Jose Montoya, the study's senior author, said: 'CFS is one of the greatest scientific and medical challenges of our time.
'Its symptoms often include not only overwhelming fatigue but also joint and muscle pain, incapacitating headaches, food intolerance, sore throat, enlargement of the lymph nodes, gastrointestinal problems, abnormal blood-pressure and heart-rate events, and hypersensitivity to light, noise or other sensations.'
The combination of symptoms can devastate a patient's life for decades.
In an effort to identify the syndrome's underlying mechanisms, Professor Montoya has been following 200 CFS patients for several years.
'In addition to potentially providing the CFS-specific diagnostic biomarker we've been desperately seeking for decades, these findings hold the promise of identifying the area or areas of the brain where the disease has hijacked the central nervous system,' he said.
Dr Zeineh added: 'If you don't understand the disease, you're throwing darts blindfolded.
'We asked ourselves whether brain imaging could turn up something concrete that differs between CFS patients' and healthy people's brains.
'And, interestingly, it did.'
The researchers compared brain images of 15 CFS patients chosen from the group Professor Montoya has been following, to those of 14 age and sex-matched healthy volunteers.
The volunteers had no history of fatigue or other conditions causing symptoms similar to those of CFS.
Their analysis yielded three noteworthy results.
First, an MRI scan showed that overall white matter content of CFS patients' brains was reduced compared to that of healthy participants' brains.
Researchers at Stanford University found three differences after performing MRIs on a group of CFS patients and a control group of healthy volunteers with no history of CFS. File picture
The term 'white matter' denotes the long, cable-like nerve tracts carrying signals and information through dispersed concentrations of 'grey matter' - which specialise in processing information.
While Dr Zeineh said the first finding wasn't entirely unexpected, the second was.
Using advanced imaging techniques, he and his colleagues identified a consistent abnormality in a particular part of a nerve tract in the right hemisphere of CFS patients' brains.
The tract, which connects the frontal lobe with the temporal lobe, assumed an abnormal appearance in CFS patients.
Furthermore, Dr Zeineh said the study identified a strong link between the degree of abnormality in the patient's tract and the severity of their CFS.
The third finding highlighted a thickening of the grey matter in the frontal lobe and temporal lobe in CFS patients, compared with the control group.
Dr Zeineh said while their results are 'quite robust', more research is needed.
'This study was a start. It shows us where to look,' he said, adding the team are planning a substantially larger study.