A new study has found that people suffering from chronic fatigue syndrome (CFS) may experience higher levels of pattern-related visual stress, a condition which causes discomfort and exhaustion when looking at repetitive striped patterns, such as text.
CFS, also known as myalgic encephalomyelitis (ME), is a disabling condition that causes persistent exhaustion. It significantly affects the sufferer’s everyday life and doesn’t get better with sleep or rest. Diagnosis of the condition is difficult as its symptoms are similar to other illnesses.
For the study, researchers from the University of Leicester examined patients with and without CFS and found that those suffering from the condition are more vulnerable to pattern-related visual stress. The findings could help in the diagnosis of CFS, as the visual system abnormalities in these patients may be an easily identifiable marker of the condition.
“Diagnosis of ME/CFS is controversial. With the exception of disabling fatigue, there are few definitive clinical features of the condition and its core symptoms, overlap with those often prevalent in other conditions,” said study leader Dr. Claire Hutchinson from the Department of Neuroscience, Psychology, and Behaviour.
“As a result, ME/CFS is often a diagnosis of exclusion, being made as a last resort and possibly after a patient has experienced a series of inappropriate treatments of misdiagnosed disorders.
“It is imperative therefore that research focuses on identifying significant clinical features of CFS/ME with a view to elucidating its underlying pathology and delineating it from other illnesses. Doing so will help researchers and health care professionals gain important insights into the condition, aid diagnosis and, in the longer term, inform evidence-based therapeutic interventions.”
To assess the vulnerability of ME/CFS patients to pattern-related visual stress, researchers used a standardized test called the pattern glare test, in which people report the number of visual distortions they experience when looking at three repetitive striped patterns of different levels of detail.
Twenty patients with CFS and 20 patients without the condition viewed three different patterns of varying frequencies. They then reported the number of distortions they experienced when viewing each pattern.
Patients with ME/CFS reported more distortions on the middle-frequency striped pattern compared to those without the condition.
“The existence of pattern-related visual stress in ME/CFS may represent an identifiable and easily measurable behavioral marker of ME. This could, in conjunction with other diagnostic tests, help delineate it from other conditions,” said Hutchinson.
The results of the study are published in the journal Perception.
Source: University of Leicester