Locked-in Syndrome: Being Trapped in Your Own Body

Locked-in Syndrome: Being Trapped in Your Own Body
Gema Sánchez Cuevas

Reviewed and approved by the psychologist Gema Sánchez Cuevas.

Last update: 21 December, 2022

It results in not being able to move any part of your body except your eyes and eyelids. Even though you lose almost all your mobility, you still have total consciousness and a functioning somatosensory system.

It’s like your brain “disconnects” from your body and loses its ability to give your body orders. But your brain keeps on receiving every kind of sensory signal like pain and temperature, and every kind of somatic signal too, like hunger.

Communication becomes almost impossible because you’re completely unable to move your vocal muscles. The only part of your body you can move is your eyelids.

It’s worth pointing out that there are cases where people have managed to communicate with their eyelids. They have a board with all the letters of the alphabet on it, and they choose the letters in the words and sentences they want to make. It’s a slow method, but it has helped give a “voice” to people who lost theirs because of this syndrome.

Symptoms, causes, and prognosis

The general symptoms of this condition are: quadriplegia, anarthria (the inability to articulate words), and still being conscious. Because neither the brain’s cortex nor thalamus are affected, there’s no change in cognitive functions. 

The patient perceives, processes, and produces information with totally normal cognitive processes. They can perceive all external stimuli, but they just can’t physically respond to them.

A human brain, locked-in syndrome.

The main cause of it is a basilar artery thrombosis. There are usually warning signs that come weeks or even months before, like dizziness or nausea. Because it’s not a vascular issue, it usually comes from a cranioencephalic trauma caused by a contusion to the brain stem or a vertebrobasilar dissection.

Depending on how severely it cuts off the patient’s motor functions, there are three types of clinical classifications:

  • Classic: this involves quadriplegia, anarthria, preservation of consciousness, and the ability to move your eyes or eyelids.
  • Incomplete: it’s similar to the classic type, but you can move a little more than just your eyes.
  • Total: no preservation of any kind of movement. This usually happens with a mesencephalon stroke.

Depending on how it develops it can either be temporary or permanent. In the cases where there’s a disconnection from the pathways that come from the pons, recovery is impossible. A disconnection of those pathways makes it so the brain’s orders never reach the rest of your body. What happens as a result is that your body can’t respond to any stimuli, even though it still receives them.

Ways to detect locked-in syndrome

It makes sense to think about how it’s hard to detect locked-in syndrome and set it apart from other things like a coma. The problem is that at first it’s not easy to figure out if the patient’s mental faculties are still intact, because they can’t communicate.

There are neurological tests that help doctors diagnose this syndrome. MRI’s can show what kind of stroke happened, and this will help them determine what it is.

Both positron emission tomography (PET) and electroencephalograms (EEG) can give doctors information about a patient’s brain activity. A  PET scan lets us see if their brain metabolism is normal. And if that’s the case, it would mean they still have all their brain functions and they’re conscious, like with locked-in syndrome.

An EEG lets us monitor the patient’s brain wave activity. This involves putting electrodes on their head. It’s a tool that helps us determine the main kind of brain waves in their head at the time. In the case of someone suffering from locked-in syndrome, what we’d see is a reactive posterior alpha rhythm.

The Diving-Bell and the Butterfly

Jean-Dominique Bauby was a French journalist who had a brain embolism at 43. After being in a coma for 20 days, Bauby woke up with locked-in syndrome. He could only move his left eye and shift his head slightly. His physical condition got much worse, and he lost nearly 60 pounds in just a few weeks.

A beautiful butterfly on pink flowers.

He lived with the illness for around a year. During the year he spent “trapped in his body,” he learned a way to communicate: an alphabet board and blinking. Thanks to the help of speech therapists and his family, he managed to write an autobiography called “The Diving-Bell and the Butterfly,” that ended up a major bestseller.

Does the cosmos contain keys for opening my diving bell? A subway line with no terminus? A currency strong enough to buy my freedom back? We must keep looking.

-Jean-Dominique Bauby-

There’s also a movie based on his book with the same name. If you watch it you’ll see what a challenge it was for Jean-Dominique. He had all these thoughts flying around his head that his body couldn’t express. He used his imagination and “traveled” to other places in his mind, so he could escape from harsh reality.


This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.