Head orientation measured with a video system.
D000886:Anthropometry / Q000379:methods*; D006257:Head; D006801:Humans; D007698:Kinesis; D008433:Mathematics; D009068:Movement; D009132:Muscles / Q000502:physiology*; D009334:Neck Muscles / Q000502:physiology*; D011187:Posture; D014743:Videotape Recording