Brain Changes in MS May Contribute to Lack of Empathy
Diffuse normal-appearing white matter damage may create disconnection in social brain network
THURSDAY, June 1, 2017 (HealthDay News) -- Subtle brain changes may explain why some patients with multiple sclerosis (MS) lose their ability to interpret social cues, according to a study published online May 31 in Neurology.
Sonia Batista, M.D., a neurologist at the University of Coimbra in Portugal, and colleagues tested 60 patients with MS and 60 healthy individuals of the same age and education level. The participants took tests to gauge their skill in inferring other people's beliefs, desires, and intentions. The participants were shown photos of people's eyes and asked to pick one of four words -- such as "anxious" or "embarrassed" -- to describe the person's feelings. Another test asked the participants to choose one of two words to describe a silent video of people interacting. Both groups underwent 3T brain magnetic resonance imaging, including conventional and diffusion tensor imaging sequences.
Imaging revealed widespread lesions in the white matter of MS patients, especially in areas key to the brain's social network. The MS patients also scored lower on both visual interpretation tests, the researchers found. On the photo test, their average score was 58.7 percent, compared to 81.9 percent for healthy participants. On the video test, people with MS averaged 75.3 percent, while healthy participants averaged 88.1 percent. Scores weren't found to be related to time since diagnosis or level of disability.
"These results indicate that a diffuse pattern of normal-appearing white matter damage in MS contributes to social cognition impairment in the theory of mind domain, probably due to a mechanism of disconnection within the social brain network," Batista and colleagues conclude.