Copy Superficial muscles of the neck Sternocleidomastoid m Superficial layer 1-Sternohyoid m 2-Omohyoid m Deep layer 3-Sternothyroid m 4-Thyrohyoid m 3 Both mm contract One m contracts Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan UniversityCopy Right- Hongqi ZHANG-Department of Anatomy-Fudan University Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University Sternocleidomastoid m. Superficial muscles of the neck Both mm contract One m contracts 1 2 3 2 4 2 2 Superficial layer 1-Sternohyoid m. 2-Omohyoid m. Deep layer 3-Sternothyroid m. 4-Thyrohyoid m