Investigation of comparative nonword repetition performance in multiple sclerosis: Group differences, subtype variations, and disability effects.

This study investigated Nonword Repetition (NWR) tasks in individuals with Multiple Sclerosis (MS) compared to healthy controls (HC), focusing on phonological working memory (WM_P). Significant differences were found in NWR acurracy (NWR_acc) score between MS subgroups and HC (H = 48.2, p < 0.001). NWR_acc decreased as the number of syllables increased in both groups, indicating increased cognitive load. All MS subtypes showed lower NWR_acc compared to HC across varying syllable lengths (Mann Whitney U Test: two syllables U = 64.5, p < 0.001; three syllables U = 183, p < 0.001; four syllables U = 248, p < 0.001; five syllables U = 283.5, p < 0.001). However, no significant differences were found within MS subtypes based on syllable length. NWR_acc did not differ between mild and severe MS groups. Overall, the NWR test effectively assessed WM_P in MS, highlighting its utility in diagnosing and addressing language-cognitive challenges in individuals with MS. This underscores the importance of tailored intervention strategies to mitigate these challenges.