Sleep abnormalities connected with this entity include insomnia affecting sleep onset and fragmented sleep followed by excessive daytime sleepiness, vocalizations, abnormal limb movements, jerks, snoring, sleep apnea and stridor during sleep (1, 36) Polysomnography with synchronized audiovisual recording is crucial during anti-IgLON5 diagnosis. Here, IGLON5 is linked to sleep apnea syndrome.