The findings of a recent study titled “Patterns of Attention Deficit in Relapsing-Remitting and Progressive Phenotypes of Multiple Sclerosis,” conducted using psychophysical tests, show that the pattern of attention impairment in patients with MS is not the same. In the relapsing-remitting form (RRMS), peripheral (exogenous) attention is more affected; whereas in the secondary progressive form (SPMS), voluntary (endogenous) attention is impaired. This distinction is important because it suggests that the neural mechanisms underlying these two types of attention impairment are different and likely involve different brain regions.
The study findings paint a complex picture of the relationship between MS types, attention disorders, and fatigue. In the relapsing-remitting type, the peripheral attention system, which is responsible for responding to unexpected stimuli, is affected by active inflammation. These patients may have more difficulty in dynamic and active environments. In contrast, in the secondary progressive type, there is a gradual destruction of voluntary attention networks, leading to impaired executive functions and planning. Fatigue plays an aggravating role in this equation. This means that fatigue is not simply a secondary symptom, but an active factor in the exacerbation of cognitive impairment. Especially in patients with a longer history of the disease, fatigue can act as a fuel for cognitive impairment. These findings emphasize the importance of “cognitive management” in conjunction with “motor management” in MS.