The cricothyroid muscle is a small muscle located in the neck, specifically between the cricoid cartilage and the thyroid cartilage. It plays a crucial role in adjusting the tension of the vocal cords, which is essential for producing different pitches in the voice. When this muscle contracts, it tilts the thyroid cartilage forward, elongating the vocal cords. This muscle is innervated by the superior laryngeal nerve, a branch of the vagus nerve. Proper functioning of the cricothyroid muscle is vital for activities such as singing and speaking, as it helps control the frequency of sound produced by the vocal cords.