Identify the muscles that act on the temporal bone, mandible, and skull in the figure below:
Temporal muscle
Pterygoid muscle
Splenius muscle
Sternocleidomastoid muscle
Temporal muscle: closes the jaw and is innervated by the fifth cranial nerve.
Pterygoid muscle: closes the jaw and is innervated by the fifth cranial nerve.
Splenius muscle: extends the head and laterally flexes the head to the same side and is innervated by the dorsal rami of the spinal nerves.
Sternocleidomastoid muscle: flexes the head and rotates it to the opposite side and is innervated by the accessory nerve and the second, third, and fourth cervical nerves.