There is a clinically relevant slowing of neuronal activity in patients with multiple sclerosis (MS) in parietotemporal cortical areas and the thalamus, strongly related to cognitive impairment, according to a recent study. These measures hold promise for the application of resting-state magnetoencephalography (MEG) as a biomarker for cognitive disturbances in MS in a clinical setting. In eyes-closed resting-state, MEG data of 83 MS patients and 34 healthy controls (HCs) peak frequencies and relative power of 6 canonical frequency bands for 78 cortical and 10 deep gray matter (DGM) areas were calculated. Linear regression models, correcting for age, gender, and education, assessed the relation between cognitive performance and MEG biomarkers. Researchers found:

• Increased alpha1 and theta power was strongly associated with impaired cognition in patients, which differed between cognitively impaired (CI) patients and HCs in bilateral parietotemporal cortices.
• CI patients had a lower peak frequency than HCs.
• Oscillatory slowing was also widespread in the DGM, most pronounced in the thalamus.