2.1. LIS_en

Search for:Search Button

Chapter 2.1.

“Locked-in Syndrome” (LIS)

• Anatomy
• Name
• Manifestations
• Environmental Perception

Parts 1. (Home/Intro) and 1a. (Mission) suggest that the focus of this website is not LIS per se, as a medical phenomenon, but (along with a certain artistic promotion) testimony about the possible taking of attitude when falling into such a state of matter (actually – into any similar state that throws one out of balance). Therefore, here comes only the most basic about LIS itself:

Anatomy

The necessary prerequisite for understanding this condition is knowing a few key details on how the brainstem works. This matter is very interesting but also rather complex/extensive! While detailed neuroscientific elaborations on it can be found in many places all over the internet (e.g., here), I offer here my simplified, layman’s scheme:

The brainstem is a neural cylindrical structure about two inches in length and about an inch in width, and it represents a connection between the brain and the spinal cord. Its lower segment (medulla oblongata) is, in fact, an extension of the spinal cord. Its upper half, which consists of a bridge (pons) and the midbrain (mesencephalon), can roughly be understood as an extension of the brain. The whole brainstem is situated inside the skull, so it is considered a part of the brain (as opposed to the spinal cord, protected by the spine).

The upper motor neurons, whose bodies are situated in the motor cortex, transmit every voluntary (more or less conscious) command for activating any skeletal muscle. These impulses’ paths to reach their final executors (muscles) comprise two dense efferent nerve fiber bundles (the pyramidal tract). They pass through the ventral (front) side of the brainstem. Also, the same type of dense fiber bundles passes through the dorsal (back) side, transmitting sensory impulses from the receptors on the body’s periphery upwards toward the brain (the afferent nerve fibers).

In short, a lesionAn area of tissue left without oxygen for a certain amount of time. This is usually due to ischemia (i.e., a drastic and relatively sudden flow reduction through a blood vessel due to spasm or a blood clot obstruction). on the ventral side of the brainstem usually results in some damage to the pons. This means a partial or complete collapse of pathways that transmit information/commands from the headquarters to the executive organs, i.e., the skeletal muscles.

However, that’s not the only problem! The brainstem is not just a classification yard for the motor-sensory fibers. It also contains centersMost are housed in the medulla oblongata, but some are also in the pons. that play an essential part in supervising some vital autonomous (unconscious) functions of the organism (e.g., breathing, swallowing, heartbeat, blood pressure, state of wakefulness, sleep cycle, and so on).

So, the mentioned lesion, other than causing a certain degree of motor function damage, can threaten the autonomous system! That threat can range (depending on the lesion’s extent) from mild nuisances to severe complications and even fatal outcomes. Until relatively recently (the end of the 20^th century), that distribution was pretty rough: most often, it would result in death and rarely in survival with certain nuisances. The area between those two extremes was very narrow, and it was a neuroscientific terra incognita—hard to recognize, complicated to maintain, and challenging to rehabilitate because an already established and efficient rehabilitation after having sustained damage in the forebrain (most often due to a stroke) doesn’t make all that much sense here.

Rapid medical advances (which include the spreading of knowledge and the development of more potent drugs) have significantly mitigated that harsh distribution, leaving behind more and more survivors in the Locked-In state of matter! It allowed for a better illumination of that terra incognita, spreading and transforming it into terra magica! That specific area after barely having escaped a close death (or rather, postponed it) is most often expressed by the strange living state of matter, which I personally call castle both in heaven and on earth (see the eponymous documentary in Chapter 2.1.1.), but generally known as LIS.

Name

LIS is an acronym for Locked-In Syndrome, which means to be locked inside one’s own body. In general, it’s the most popular (and rightly so) and widely spread term for the utterly confusing possible Not all brainstem strokes are devastating enough to result in LIS. For example, my first stroke also hit my brainstem, leaving me heavily disabled but by no means locked inside myself.state after having suffered a brainstem stroke. Typically, like in my case, the lesion affects the prominent part of the brainstem’s upper half: the pons (the bridge between the brain and the spinal cord), but often also the medulla oblongata (spinal cord’s extension, myelencephalon). It’s a social/functional term explicating the newly emerged existential regard of an individual towards himself. But at the same time, according to the breakdown of the mentioned functions, it also implicates a (sudden) absence of the ability to somehow impact the outside world and to take part in life.

Although initially correct, the further development of that condition poses a real challenge: not letting the implication surface and impose itself as a definition! Not allowing Locked-In to turn into Locked-Out! (or, given the current global situation, not letting Lock Down turn into Knock Down!)

At the beginning of the millennium (no matter how rarely that condition was even identified and how seldom the patient even lived long enough to become a case), we were often met with different names for it:
– regarding the location of the lesion: ventral pontine syndrome or,
– physio-functional: deeferentation syndrome.

In a broader sense of the word, due to the similarity of the problem’s manifestation, I think that this socially functional term (LIS) can be used for any other similar state that occurs as a consequence of some other neurological deficits, e.g., advanced stages (which are often, unfortunately, terminal) of a rare progressive neurological disease, like multiple sclerosis (MS) or amyotrophic lateral sclerosis (ALS). (Here the term “locked-in” is maybe even more appropriate!)

Manifestations

So, the most obvious problem is the inability to control motor skills willingly. But that problem is often enriched with hardly perceivable stronger or weaker tantrums of certain autonomous functions. All of it, in turn, manifests through a series of occurrences (symptoms) whose intensity and extent of the possibility of rehabilitationSome brainstem stroke survivors do get somewhat better physically (more rarely), some barely noticeably (more often), and most of them succumb pretty quickly—partly because of giving up and partly because of the accompanying objective difficulties. depend heavily on the size/location/duration of the lesion caused by the stroke (i.e., they are conditioned by the consequent extent of the damage to the brainstem). My LIS featured the following list of such symptoms.

• The inability to move neither legs nor arms (quadriplegia/quadriparesis).
• Difficulty breathing (more precisely, controlling the inhale-exhale mechanics ranging from complete dysfunction, which requires the constant aid of the ventilator, to various degrees of autonomous breathing impairments).
  Generally, breathing is an autonomous process controlled unconsciously, and the responsibility of the “autopilot,” i.e., the breathing center situated right in the brainstem (or more precisely, in the already mentioned medulla oblongata). Therefore, if the lesion affects the broader area around (below) the pons, the function of controlling the breathing dies out as well (the said autopilot completely cancels that service), so the patient is left to depend on the help of the ventilator (a machine for external stimulation of inhaling/exhaling) . . .
  Of course, once again—depending on the size of the lesion, such giving out can also be partial: my intercostal muscles are entirely without the control of the central nervous system. But my diaphragm is still under the control of the spared part of that autopilot, so I can still breathe independently, even if it is only abdominal breathing (which is the most important), but alas—it’s immensely shallow!
  A deep inhalation/exhalation/holding my breath in my lungs on command (a voluntary breathing upgrade that is possible to learn/train)—no way! (There is somewhat of an exception—a sporadic, completely autonomous deep inhale activated by the auto co-pilot when he estimates that there isn’t enough oxygen in the blood, i.e., that there’s too much carbon dioxide. A mechanism similar to yawning, only without the accompanying immense spasm.)
• The inability of vocal speech. It’s most often assessed as aphasia, but there’s a significant (though unobvious) characteristic: in all types of aphasia, the problem is central! The damage affects one or both speech centers in the cerebral cortex (Broca/Wernicke’s areas), but the speech apparatus remains intact. In LIS, however, it’s the opposite: the cortex (including the mentioned areas) is spared, but the speech apparatus is affected. More precisely (because there is no mechanical damage)—it is deprived of the impulse inflow, which would make it work. So, in that case, it’s more accurate to talk about the inability to produce sounds (a-/dysphonia) and their articulation (an-/dysarthria).
• Difficulty swallowing or the inability to do so (a-/dysphagia).
• Fecal and urinary incontinence due to the absence of the voluntary control of sphincters (at least in the beginning).
• Mind (intellectual abilities, cognitive brain function) and emotions built throughout life remain intact. The person is aware of everything around them, which initially seems frustrating, but later, it can be beneficial (dare I say crucial) in rehabilitation.
• Finally, there is a tendency to develop decubitus. (Bedsores: a frequent complication, not directly connected to the stroke, but still very uncomfortable and an aggravating circumstance in the care for any patient that’s been lying down for a long time.)

Environmental Perception

The majority of LIS survivors give up very quickly—either because of the objectively tricky situation that hit them or because of inadequate care and concern (more precisely, adequate non-care) of broader social structures to help in times of need. Namely, if someone does realize that there still is an entirely consistent spirit inside the corporeal debris, a being that thinks, understands, and feels, it is usually only their closest family members/friends; rarely (but fortunately now more often) some directly involved doctors.

In principle, the authorities in charge of such affairs do have the ear/goodwill for a favorable concrete (re)action, but it is damn hard to reach them. An impenetrable bureaucratic wall separates the masses from the executive power. One becomes an anonymous labeled case (such that does not fit into any box—especially regarding rare diseases/conditions) and remains hanging in a vacuum that fills the space between valid regulations. Rarely does someone from that administrative bulwark perceive the applicant outside the context of the form as a human being who needs help . . .