Relative effect of lesion-independent thalamic atrophy on information processing speed in multiple sclerosis

Cognitive impairment in multiple sclerosis is thought to arise from both focal inflammatory lesions and compartmentalized neurodegeneration. Prior work has established strong links between thalamic atrophy and slowed information processing speed, but most analyses have treated the thalamus as a uniform structure and have not rigorously adjusted for lesion effects.

This study seeks to disentangle lesion-mediated versus lesion-independent thalamic degeneration by comparing nucleus-specific associations with the Symbol Digit Modalities Test before and after adjusting for total lesion volume. The authors motivate the need to clarify the relative effect of lesion-independent atrophy on information processing speed as a critical unresolved issue in MS pathophysiology.