April 16, 2021

“It Is Not As If I Am Paralyzed”: Anosognosia, a Lack of Insight

Written by: Marina Peric, M.D.
Reviewed by: Mubashar Rehman, PHD

Do you happen to know a person with dementia? As their condition progresses, you can see how their memory and other cognitive functions deteriorate. But can they prevent it? According to researches, 20-81% of patients with dementia are unaware of their impairment.

This is what we call anosognosia, a neurological condition in which the patient is unaware of their deficit, physical or psychological. Anosognosia is a common companion of dementia but is not strictly reserved for it. It is a common sign of illness that can be seen in various neurological and psychiatric diseases and conditions.


A Quick History Review

First descriptions of patients, who are unaware of their deficit, date back from the end of the 19th century. These cases mostly referred to patients who, after suffering a brain injury due to which they’re unable to see, deny their blindness and can even describe what they “see” around - the condition known as Anton’s syndrome.

But the first actual description of anosognosia as such came from the famous neurologist Babinski in 1914. He described it as a lack of awareness of paralysis in patients who suffered a stroke but had normal cognitive functioning. Babinski was also the one to coin the term anosognosia, which translates as “lack of knowledge of disease”.

Since then, the use of the term has expanded, so now it can also be used for cognitively impaired patients (such as those with dementia, for example), and all sorts of deficits.


Anosognosia Causes

Typical anosognosia occurs after a brain injury or a stroke. It can also be seen in psychiatric conditions, where patients minimize or deny their symptoms. This is similar to dementia and Alzheimer’s where patients tend to deny their memory deficit.

It is known that anosognosia is more likely to develop when the right side of the brain is damaged, but the underlying reasons are unclear. Possible explanations of anosognosia include using denial as a defense mechanism, confusion, emotional numbness, impaired perception, etc. The exact cause and mechanism of anosognosia development are yet to be discovered.


Life with Anosognosia

You may be asking yourself, how is it possible that one is completely unaware that, for example, a side of their body is paralyzed, or that they don’t see. How does one not notice they’ve become so forgetful lately?

It is difficult to answer. Anosognosia is one of the most intriguing, astonishing phenomena in neurology. Sometimes, a patient denies some deficits but recognizes the other.

To justify it, patients will bring up all sorts of explanations. If you’d ask them to, for example, move their paralyzed arm, they’d say, “Here, I’ve moved it”, of course, without really moving it. And such a patient would not be trying to fool anyone, they’d firmly believe what they’d be saying. When a paralyzed patient of Babinski was prescribed electrical stimulation treatment, he found himself confused. “It is not as if I am paralyzed”, he said.

Sometimes, this goes so far, that the patients completely neglect the affected body parts - as if they simply did not exist. They’d, for example, only comb the hair on one side of the head, have difficulties dressing the affected parts of the body up, be unable to pay attention to a paralyzed limb, and so on. Still, neglect and anosognosia are two different entities that may co-occur, but this is not a rule.


Anosognosia and Dementia

Dementia is defined as a loss of intelligence that one once possessed. Patients with dementia cannot use their brain functions to the full potential, which reflects on their work, daily, and social life. The condition gets worse over time, and treatment options are still very limited.

The typical symptoms of dementia are the so-called 4 A’s: amnesia (loss of memory), agnosia (loss of perception), aphasia (loss of language ability and reduction of vocabulary), and apraxia (problems with coordination of movement in space). Although anosognosia is common, yet it is usually an underrated symptom of dementia.

People who suffer from dementia show a variable degree of awareness for their diagnosis and overall situation. Anosognosia in these patients usually refers to their lack of awareness for memory loss, but there may also be a lack of awareness for the disrupted daily life or social life. Not every patient with dementia has anosognosia - as the percentage reported in the literature varies between 20 and 81. Anosognosia is more common in patients with Alzheimer’s than in other types of dementia.


Diagnosing Anosognosia in Patients with Dementia

Unlike anosognosia in patients with, for example, paralysis or blindness, diagnosing anosognosia in patients with dementia is much trickier as the symptoms are not always that obvious.

Whether a patient with dementia has anosognosia can be done in several ways:

  • A doctor can make a simple evaluation of the patient’s insight.
  • A doctor can evaluate the functionality of the patient, and then compare it to the evaluation done by the patient – the bigger the difference, the greater the degree of anosognosia.
  • A patient can be asked to complete a task, and then evaluate how successful they think they were at it. The objective successfulness is then compared to the patient’s evaluation, The bigger the difference, the greater degree of anosognosia is present.

Anosognosia in patients with dementia is rated as follows:

  • Patient admits the memory loss.
  • Patient admits a small amount of memory loss.
  • Patient is not aware of any loss of memory.
  • Patient strongly insists that there is no loss of memory.

How to Help Someone with Anosognosia?

There is no specific treatment for this condition. Cognitive therapy with a specialized psychiatrist can be helpful for these patients. Other treatment options are limited.

Due to the lack of insight into their own disease, the patient will often refuse to take part in the treatment. This is why it is paramount that not only the patients but their family members are also included in the process from the start. They must be educated on how to deal with the problem in the specific case, maintain a positive approach, and provide a safe environment for the patient. 

Anosognosia caused by a brain injury or a stroke may improve over time. On the other hand, in patients with dementia or psychiatric illnesses, it usually persists or gets worse. The prognosis is overall poor for all patients and followed by a poor quality of life.



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Article written by Marina Peric, M.D.
Marina is a medical doctor from Belgrade, Serbia. She graduated with high honors in 2020 and is aspiring to become a pathologist. During her studies, she took part in several scientific researches, mostly in the pharmacology niche. She was also an assisting teacher at the Department of Histology and Embryology for 5 years (2015-2020). Marina has years of experience as a writer on health-related topics. Apart from English, she fluently speaks several languages, including Spanish, Russian, and Czech.

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