<unk>  (commonly referred to as head-banging) is a parasomnia.
Jactatio capitas nocturna
Chondrodermatitis nodularis chronica helicis
Granulosis rubra nasi
Trichostasis spinulosa
Ichthyosis bullosa of Siemens
Phlegmasia cerulea dolens
Hydroa vacciniforme
Hirsuties coronae glandis