Locked-In Syndrome

What is locked-in syndrome?

Locked-in syndrome (LiS) is a rare nervous system disorder with severe effects on daily life. People with LiS are awake and able to think and understand, but they can’t move their body or speak.

LiS happens from damage to the part of the brain near the spinal cord that controls movement and coordination. This damage causes people to become paralyzed and unable to chew, swallow, talk, or show facial expressions.

Symptoms of LiS

LiS symptoms are usually severe but can be very different among people who have the condition. People with LiS can hear, understand, think, and sleep normally even though they can’t move or speak. Most people with LiS can blink and move their eyes up and down but not side to side. People with “incomplete LiS” may have some feeling and limited movement in some parts of their body.

Living with LiS depends on its cause and the amount of support available to a person who has it. Most people with LiS don’t get back the ability to move their body. But physical therapy, devices that help people communicate, and specialized care can make daily life easier and more meaningful. 

Who is more likely to get locked-in syndrome?

LiS mostly affects people between ages 30 and 50. People who are at a higher risk for having a stroke are also at a higher risk for getting LiS. Substance misuse can raise a person’s risk of stroke.

LiS may be caused by:

• A stroke caused by a blood clot or bleeding in the brain
• Infection in certain parts of the brain
• Tumors in the bottom part of the brain
• Amyotrophic lateral sclerosis (ALS)
• Guillain-Barré syndrome 
• Traumatic brain injury
• Diseases that damage myelin (a substance that covers and protects nerve cells)

How is locked-in syndrome diagnosed and treated?

Diagnosing LiS 

LiS may not be recognized by a doctor because the person appears unconscious. Many people with LiS are in a coma until they wake up—when they are aware of their surroundings but can’t move or speak. 

To diagnose LiS, a doctor examines the person and reviews their medical history and symptoms. Ruling out other conditions can involve doing different tests: 

• Blood tests, such as those that check levels of sodium (rapid changes in sodium can damage brain cells affected in LiS)
• Special imaging tests that show how blood flows through the brain can reveal blood clots in the brain that can cause LiS
• Collecting small samples of spinal fluid can help doctors decide if an infection or immune-related condition is causing LiS
• Electroencephalograms (EEGs) are tests that measure brain activity and can identify problems with sleep
• Electromyography (EMG) tests help doctors check whether muscles or nerves are damaged
• Other special electrical tests can measure whether senses like sight, hearing, and touch are working by checking whether signals can travel from the body to the brain
• Brain scans like MRIs (magnetic resonance imaging) and CTs (computed tomography) let doctors see where and how the brain has been injured, which can help inform treatment

Find out more about neurological diagnostic tests and procedures. 

Treating LiS

Although there is no cure for LiS, many treatments can help people live with the condition. 

For example, a tracheotomy (a tube inserted into the neck) can help a person with LiS breathe. People with LiS who can’t eat or swallow usually have a feeding tube that delivers food, fluids, and medicines safely into their stomach.

Other supportive care can help reduce the risk of complications like pneumonia, urinary tract infections, blood clots, and bedsores (which can be caused by sitting in one position for a long time). Physical therapy can help stiff muscles become stronger and more flexible. This can help people maintain the ability to move their arms and legs. 

Speech therapy can help people with LiS communicate more clearly. Specialized tools such as eye-tracking computers, letter boards, and other devices that let a person communicate using eye movements can help people with LiS express themselves. Physical therapy and motorized devices like wheelchairs, can help people with LiS get around. 

What are the latest updates on locked-in syndrome?

The National Institutes of Health (NIH), which includes NINDS, is the leading federal funder of research on the brain and nervous system, including disorders such as LiS. NIH supports innovative research to better understand, diagnose, and treat LiS.

For example, NINDS-funded researchers are adapting a technology used by people with epilepsy to help people with LiS communicate by decoding speech from brain signals.

A study funded by NIH’s National Institute of Deafness and Other Communication Disorders aims to help people with LiS communicate using a wireless device that reads signals directly from the brain and translates the signals into speech. 

NIH-funded scientists are testing an implantable brain device that sends electrical signals to brain regions that control movement and speech to help people with LiS communicate. 

For more information on research about LiS, check NIH RePORTER, a searchable database of current and past research projects funded by NIH and other federal agencies. RePORTER also has links to publications and resources from these projects. 

For research articles and summaries on LiS, search PubMed, which contains citations from medical journals and other sites. You can use keywords like "locked-in syndrome" or "LiS" in your search.

How can I or my loved one help improve care for people with myotonia congenita?

Consider participating in a clinical trial so clinicians and scientists can learn more about LiS and related disorders. Clinical research with human study participants helps researchers learn more about a disorder and perhaps find better ways to safely detect, treat, or prevent disease.

All types of participants are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races, and ethnicities. This helps to make sure that study results apply to as many people as possible and that treatments will be safe and effective for everyone who will use them.

For information about participating in clinical research visit the NINDS Clinical Trials site and NIH Clinical Research Trials and You. Learn about clinical trials currently looking for people with LiS at ClinicalTrials.gov, a searchable database of current and past clinical studies and research results.

Learn about related topics 

• Amyotrophic Lateral Sclerosis (ALS)
• Stroke