A breakdown of spasmodic dysphonia, the cause of RFK Jr.'s shaky voice, including its history, causes, and treatments.
By
Patrick Campbell
| Published on January 30, 2025
5 min read
RFK Jr. speaks during his Senate confirmation hearing on January 29, 2025.
Credit: AP Photo/Ben Curtis
As Robert F. Kennedy Jr. has become a more prominent figure in the political landscape within recent years, including his January 29, 2025 US Senate confirmation hearing, many who are unfamiliar with the politician may be left wondering why his voice sounds, at times, strained and shaky.
The reason? Spasmodic dysphonia, a neurological disorder affecting approximately 1 in 100,000 US adults.
In a 2024 interview, RFK revealed he started experiencing symptoms and was diagnosed at 42 years old. Though not considered progressive, the condition is chronic and without an existing cure, meaning RFK Jr., now 71 years old, will deal with the effects of this disease for the remainder of his life.
Spasmodic dysphonia (spasmodic dysphonia) is a rare neurological voice disorder that causes involuntary spasms in the muscles of the vocal cords, leading to interruptions in speech. These spasms can make the voice sound strained, shaky, or breathy, depending on whether the condition affects muscles that close (adductor type) or open (abductor type) the vocal cords. The exact cause of spasmodic dysphonia is not fully understood, but it is believed to result from abnormal nerve signaling in the brain, particularly in areas that control muscle movement. While spasmodic dysphonia does not affect overall health, it can significantly impact communication and quality of life.
Spasmodic dysphonia was first described in medical literature in the late 19th century. In 1871, Ludwig Traube, a German physician, documented a condition resembling spasmodic dysphonia, referring to it as a "nervous hoarseness."
However, spasmodic dysphonia was not widely recognized as a distinct neurological disorder until the mid-20th century. In the 1960s and 1970s, advancements in laryngology and neurology helped differentiate spasmodic dysphonia from psychogenic voice disorders, solidifying its classification as a form of focal dystonia.
The exact cause of spasmodic dysphonia is not fully understood, but it is believed to be a neurological disorder that affects the way the brain controls the muscles of the vocal cords. Research suggests that spasmodic dysphonia results from abnormal signaling in the basal ganglia, a part of the brain responsible for coordinating movement. It is classified as a type of dystonia, a group of movement disorders characterized by involuntary muscle contractions.
While most cases of spasmodic dysphonia occur without a clear trigger, some individuals report the onset of symptoms following respiratory infections, voice overuse, stress, or trauma to the head or neck. There may also be a genetic component, as spasmodic dysphonia sometimes runs in families. However, no single gene has been definitively linked to the disorder.
There is no cure for spasmodic dysphonia (spasmodic dysphonia), but several treatment options can help manage symptoms and improve voice function. The most common and effective treatment is Botox injections, which temporarily weaken the overactive vocal cord muscles, reducing spasms and improving speech. The effects typically last 3 to 6 months, requiring repeated injections.
For patients seeking longer-lasting solutions, selective laryngeal denervation-reinnervation surgery is an option. This procedure involves cutting and reconnecting nerve pathways in the larynx to reduce involuntary spasms. Other experimental approaches, such as deep brain stimulation and neuromodulation techniques, are being explored to target the underlying neurological dysfunction of spasmodic dysphonia. Additionally, speech therapy can help patients develop compensatory techniques to improve voice control, though it is generally used in combination with other treatments.
Helpful Links to Learn More:
National Institute on Deafness and Other Communication Disorders (NIDCD) – Provides an overview of spasmodic dysphonia, including its classification as a neurological disorder affecting voice control. Source: NIDCD, Spasmodic Dysphonia
Dystonia Medical Research Foundation (DMRF) – Discusses spasmodic dysphonia as a form of laryngeal dystonia, its potential causes, and available treatment options. Source: DMRF, Spasmodic Dysphonia Information
Mayo Clinic – Covers common symptoms, possible triggers (e.g., infections, stress, and trauma), and emerging treatments such as selective laryngeal denervation-reinnervation (SLAD-R). Source: Mayo Clinic, Spasmodic Dysphonia