You hear a loud noise behind you and look back over your left shoulder.Which of the following is true?
A) This was a contralateral contraction of your right sternocleidomastoid muscle.
B) This was a contralateral contraction of your left sternocleidomastoid muscle.
C) This was an ipsilateral contraction of your right sternocleidomastoid muscle.
D) This was an ipsilateral contraction of your left sternocleidomastoid muscle.

Question

Quizplus · Accepted Answer

Looking over your left shoulder involves the contraction of the right sternocleidomastoid muscle, which is on the opposite side of the direction you're turning, hence a contralateral contraction.

You Hear a Loud Noise Behind You and Look Back