LGI1 and Cognitive impairment: The remarkably rapid anti-seizure effect of early immunotherapy in FBDS, the frequent transition from FBDS alone to cognitive impairment, low frequency of IgG1-LGI1 antibodies in patients without cognitive impairment, plus previous preliminary observations (Irani et al., 2011), generated the hypothesis that cognitive impairment could be prevented by termination of FBDS.