Emotional disturbances in multiple sclerosis: A neuropsychological and fMRI study

Background: Emotional disturbances in multiple sclerosis (MS) are often explored in terms of affect recognition, with controversial results that likely reflect the high lesional heterogeneity. Patients' emotional experience, however, has seldom been studied and has never been explored using fMRI.

Objectives: To explore the emotional experience in MS and compare these data with fMRI measurements using for the first time real-life emotional scenes differing in valence and arousal.

Methods: Twenty-five right-handed women with relapsing-remitting MS and 27 right-handed age-, sex-, and education-matched healthy controls visualized during an fMRI session, emotional scenes taken from the international affect picture system (IAPS) and differing in valence (positive, negative, neutral) and arousal (ranging from calm to excited). During a post-scanning debriefing, participants were asked to look again at each image and score it in terms of valence and arousal sensation on a scale of 1-9.

Results: Cognitively well-preserved MS subjects presented a significantly more scattered emotional experience compared to controls in response to positive and negative pictures. In fMRI, MS patients also presented a higher variability of response when compared to controls in left inferior orbitofrontal cortex for positive stimulations. For negative condition, no significant results were observed between the two groups. However, a trend was detected in left amygdala, right fusiform gyrus, right caudate nucleus and right pallidum for negative stimulations.

Conclusion: In response to emotional stimuli, MS subjects presented a scattered emotional experience subtended by a greater variability of brain response, highlighting an emotional pattern not previously reported in MS patients.