Importantly, the synaptic CASPR1/CNTN1 complex is strongly decreased and the functional synaptic changes occur at an early, pre‐clinical stage of optic neuritis/EAE before the onset of obvious morphological alterations in the optic nerve that subsequently occur at a later time (Fairless et al, 2012; Stojic et al, 2018). Here, CNTNAP1 is linked to optic neuritis.