Which of the following is an example of a functional voice disorder?

A functional voice disorder primarily arises from the misuse or overuse of the vocal apparatus, rather than from structural abnormalities or medical conditions. Muscle tension dysphonia fits this definition perfectly, as it results from excessive tension in the laryngeal muscles leading to disrupted voice production without any identifiable physical pathology. This disorder often stems from factors such as stress, vocal misuse, or overexertion, all of which affect the way the vocal folds vibrate and can lead to changes in voice quality.

In contrast, other conditions listed, such as vocal fold paralysis, vocal cord nodules, and laryngeal cancer, are considered organic disorders. Vocal fold paralysis refers to the inability of the vocal folds to move properly, which is typically due to nerve damage. Vocal cord nodules are benign growths caused by repetitive strain or overuse of the voice and indicate a structural change, while laryngeal cancer involves malignant growths that have a clear pathological basis. Thus, the focus on muscle function and tension is what distinctly categorizes muscle tension dysphonia as a functional disorder.