People with multiple sclerosis (MS) suffer from a wide range of symptoms that can affect their brain, spinal cord, and vision, but the disease's symptoms are often thought to be merely physical. However, patients may also suffer from an impaired ability to understand how others feel, which may be tied to subtle brain changes, according to new research.

In a small study, published in the online issue of Neurology, researchers studied social cognition in a group of 60 people with MS and 60 healthy individuals. They found that those with MS had lower scores on two tests that determine how well you can interpret others' emotions, including beliefs and desires. Scores were related to how much damage the patient had sustained in a part of the brain known as the social brain.

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"Understanding how MS affects the 'social brain' has not been well studied, but the ability to interpret other people's feelings and intentions may influence people's ability to maintain a job and their relationships with family and friends,” study author Sonia Batista said in a statement. "These skills are very important for people with MS since having good support is one of the main factors in whether people have a good quality of life."

The study participants had been diagnosed with the debilitating disease for an average of 11 years. Fifty of the subjects had the relapsing-remitting form of the disease and the others had secondary progressive MS. The relapsing-remitting form of the disease involves periods of new symptoms or relapses that occur over days or weeks and then they tend to improve. After the relapses, remission can last months or years, according to Mayo Clinic.

All of the participants took tests that measure theory of mind skills, which is the ability to understand how others’ mental states, including beliefs and desires, may be different from one’s own. One of the tests involved facial photographs, in which participants had to select a word that best described the person's emotion in the photo. Another similar test involved silent video clips of people interacting. Subjects had to choose the best word to describe the conversation. Those with MS received lower scores than the healthy people on both tests.

In addition to the theory of mind skills tests, all of participants had various types of brain scans. The researchers found that the test results of the people with MS weren’t related to how long they had the disease, but rather the degree of damage each participant had in a specific region of the brain.

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"It appears that there is a disconnect in the social brain network," Batista said.

She notes further research needs to be conducted to better understand how social problems affect people with MS. The disease is most diagnosed between the ages of 20 and 40. Its symptoms are often unpredictable, but some of the most common ones include fatigue, visual disturbances, altered sensations, and difficulties with mobility. It affects more than 2.3 million people worldwide, according to the National Multiple Sclerosis Society.

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