GRM5 and Cognitive impairment: For this, three synaptic antigens were selected based on their molecular key role in cognitive function and for being established targets in antibody-mediated inflammatory brain diseases with predominant amnesia and cognitive impairment [25, 26]: the N-Methyl-D-Aspartate receptor (NMDAR), Leucine-rich, glioma inactivated 1 (LGI1) and the metabotropic glutamate receptor 5 (mGluR5).