My daughter was born nonverbal, and through her journey I have seen the unique challenges faced by people who cannot speak.

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Research has shown that facial muscle differences exist in nonverbal individuals, but what has never been systematically tested is whether the nerves that control these speech muscles are functioning. When there is a complete lack of ability to see or hear, we test:

• The optic nerve for vision
• The auditory nerve for hearing

Yet for speech, the essential nerves that make fine tuning sound into words possible have never been assessed in those who cannot speak.

For those who can’t speak, we must begin testing the nerves that are essential for producing sound and forming words:

• Vagus nerve and its External Branch of the Superior Laryngeal Nerve (EBSLN): control the vocal cords and allow sound to begin

• Hypoglossal nerve: controls tongue movement needed to form words

• Higher motor pathways: deliver brain signals to these nerves so speech can occur

If these systems fail, the result is not distorted or muffled speech, but a complete inability to speak. Yet, these have never been tested for function in those who can’t speak.

Why can some nonverbal individuals still make sounds if the external branch of the superior laryngeal nerve (EBSLN) is involved?

Just as a blind person can still move their eyes even though the optic nerve cannot transmit vision, a person can still make sounds when the external branch of the superior laryngeal nerve is impaired because the muscles that produce sound still work but the fine motor control needed for clear speech does not.

The typical process for those who can’t see/hear that should also be applied to nonverbality:

• Diagnosis: Identify which mechanism is malfunctioning and causing nonverbal speech outcomes.
• Prognosis: Determine if it can be repaired or if accommodations are needed.
• Treatment: Target the dysfunction to restore speech.
• Accommodation: When speech cannot be restored, provide early and effective communication supports.

A few initial options for testing include:

• Facial electrodiagnostic tests (PMID: 32270328): These tests use small electrical impulses to check whether the nerves that control facial and speech-related muscles are sending signals properly. They help identify if a nerve is damaged, weak, or not responding at all.
• MRI of facial nerves (PMID: 23766904): This imaging method allows doctors to actually see the nerves that control speech. High-resolution MRI can show if the nerve is missing, compressed, inflamed, or otherwise abnormal.

Why this matters:

• They have been placing blame on cognitive ability without first testing mechanistic explanations. 
• Accurate diagnoses and effective therapies remain out of reach without this knowledge
• Testing could lead to interventions that help nonverbal individuals find their voice or receive better early supports

Call to Action:

Healthcare providers, researchers, and policymakers must make this a priority. Please support this petition to ensure nerve function testing for speech production is developed and implemented.

Nonverbal individuals deserve an established diagnostic, prognostic, and treatment/accommodation protocol just like those who can’t see or hear have. I know from first hand experience, no further functional tests are done when your child can’t speak. Parents are just given a folder of community resources for how to handle their child’s emotional and behavioral responses to their trapped cognizance.

By filling this critical gap, we can give nonverbal individuals a fair chance to be heard.