Furthermore, LGI1-IgG1 antibodies were undetectable in 7/8 (88%) patients without cognitive impairment versus 14/41 (34%) with cognitive impairment (P = 0.01, Fisher’s), and greater LGI1-IgG1 proportions correlated modestly with poorer cognitive scores (P = 0.01 and 0.04, Supplementary Fig. 2B and C). Here, LGI1 is linked to Cognitive impairment.