Robert F. Kennedy Jr. started developing symptoms of the condition in 1996. Spasmodic dysphonia is a neurological condition that causes certain muscles in the “voice box,” or larynx, to spasm, often making the voice sound raspy, strained or breathy.

Spasmodic dysphonia is a rare neurological disorder that causes involuntary spasms in the vocal cords, making speech strained, breathy, or hoarse.

Spasmodic dysphonia (SD), sometimes referred to as laryngeal dystonia, is a rare neurological condition impacting the voice and speech that impacts approximately 50,000 people in North America. For people with SD, muscles spasms in the larynx (also known as the voice box) cause the voice to sound tight, strangled or strained.