What is anosognosia?
Anosognosia is a condition where you can’t recognize other health conditions or problems that you have. Experts commonly describe it as “denial of deficit” or “lack of insight.” It falls under the family of agnosias, all of which happen when your brain can’t recognize or process what your senses tell it.
This condition can happen with mental illnesses, keeping a person with a disorder like schizophrenia from recognizing that they have a condition and need to take their medication. It can also happen with conditions that affect your body, such as stroke.
Who does it affect?
Anosognosia affects people with other medical conditions, especially certain mental health conditions. It is most common with certain conditions, including:
How common is this condition?
Anosognosia is incredibly common with certain mental health conditions. Experts estimate that it affects between 50% and 98% of people with schizophrenia, about 40% of people with bipolar disorder, and more than 80% of people with Alzheimer’s disease. It also happens to between 10% and 18% of people who have one-sided paralysis after a stroke.
How does anosognosia affect my body?
Your brain keeps track of what’s going on with your body using a “self-image.” If you have an injury, your body updates your self-image to reflect that, and it will keep updating as your body heals. People with anosognosia have damage in the areas of their brain that update their self-image.
Because that person’s mind can’t update their self-image, they can’t process or recognize that they have a health problem. That’s what makes this condition different from the kind of denial described by the Kübler-Ross model (commonly known as the five stages of grief). A person in denial rejects or avoids accepting reality because it’s unpleasant or distressing. A person with anosognosia can't recognize the problem at all.
Because they can’t recognize they have a medical problem, people with this condition often don’t see the need to care for that problem. In more severe cases, they actively avoid or resist treatment.
Symptoms and Causes
What are the symptoms of anosognosia?
People with anosognosia usually show that they can't recognize a medical problem they have, either through action or what they say. In some cases, people with this condition will rationalize what’s happening to them, or they may try to cover up symptoms. They may recognize some symptoms but not others.
Anosognosia means a person can’t do one or more of the following:
- Recognize that they have an illness or medical problem.
- Recognize the signs and symptoms of the condition that they experience.
- Connect their signs and symptoms to that condition.
- Understand and agree that the condition is serious and needs treatment.
In some cases, a person with this condition may avoid the truth about their condition, and they might do so consciously or without even realizing it. Some might confabulate, which is when a person’s mind fills in gaps in their memory with false memories.
Anosognosia can also happen in certain ways with specific symptoms, with some examples below.
One-sided sensory and movement problems
Anosognosia got its name from French neurologist Joseph Babinski in 1914, who created the term to describe someone who’d lost the ability to use or feel the left side of their body. That person was unaware of the problem, even though they couldn’t use the left side of their body.
Anosognosia that has this one-sided effect more commonly affects the left side of your body, but it can affect the right side. The two key symptoms that happen with this are:
- Hemiplegia. Pronounced hem-ee-plee-gee-uh, this is paralysis on one side of the body. A person with anosognosia who can’t move one side of their body will still believe they can.
- Hemisensory loss. This is a loss of your senses, including vision, hearing and touch, on one side of your body.
Anton’s syndrome (visual anosognosia)
Anton’s syndrome is an extremely rare type of anosognosia that affects eyesight in one of two ways:
- Denial of blindness. This is when a blind person can’t recognize that they are blind. This usually affects both eyes, but there are a few exceptions. One such exception is "gun-barrel vision," when a person can see only in the center of their field of vision.
- Denial of vision. This is when a person says and believes they're blind but shows signs they can still see. This type is much rarer than denial of blindness.
What causes anosognosia?
Anosognosia can happen for many different reasons, all of which fall into one of two categories:
- Brain damage.
- Degenerative diseases.
Your brain is prone to injury like any part of your body. Damage to your brain causes injuries called lesions. Lesions that cause anosognosia can happen for any of the following reasons:
- Brain tumors (including cancerous and non-cancerous growths).
- Head injuries such as concussions or traumatic brain injuries (TBIs).
- Cerebral hypoxia (brain damage from lack of oxygen).
- Infections (such as those that cause encephalitis).
- Seizures and epilepsy.
- Sleep apnea.
- Toxins, such as carbon monoxide poisoning.
Many different brain diseases disrupt your brain’s network of connections. That kind of disruption can affect your ability to update your self-image, leading to anosognosia. Conditions that cause or involve this kind of disruption include:
- Alzheimer’s disease.
- Bipolar disorder.
- Huntington’s disease.
Is it contagious?
Anosognosia isn’t contagious.
Diagnosis and Tests
How is anosognosia diagnosed?
Anosognosia is effectively invisible unless a provider already knows you have a health problem and they see the signs that you don’t recognize that problem. In many cases, that means a provider first has to diagnose a condition that's having a significant impact on your life. Then they have to see signs that you can't recognize that problem, leading them to suspect anosognosia.
It's also common for people with anosognosia to rationalize or cover up signs of health problems, which happens because their mind tries to fill in the gaps for what it can’t explain or understand. Because of that, diagnosing this condition often requires a combination of the following:
- A physical and neurological exam.
- Asking questions about a person’s health history and life circumstances.
- Diagnostic testing and imaging.
What tests will be done to diagnose it?
Diagnostic and imaging tests that are possible with anosognosia include, but aren’t limited to, the following:
Management and Treatment
How is anosognosia treated?
Anosognosia is difficult to treat and isn't curable. When it happens because of an injury to your brain, treating the underlying injury may help this condition over time. However, some people will have lingering or even permanent effects.
Anosognosia also isn't treatable when it happens because of degenerative diseases. But some forms of therapy and treatment programs may help a person with this condition.
What medications or treatments are used?
There are no treatments or medications that directly help anosognosia. Therapy and treatment programs can help a person with anosognosia develop habits that compensate for this, but these do not treat the condition itself.
What are the possible complications with this condition?
The possible complications with anosognosia depend entirely on the disorder that the person has but can't recognize. That's because people with anosognosia can't recognize they have a problem, which means they're less likely to accept and undergo treatment.
Because the complications can vary so widely, a healthcare provider is the best person to explain the possible complications. They can tailor the explanation and information to the specific situation affecting you.
How can I take care of myself or manage symptoms?
Anosognosia isn't a condition that you should try to self-diagnose or treat on your own. That’s because this condition often happens along with much more serious conditions that need care from a trained, experienced healthcare provider.
How can I reduce my risk of developing anosognosia or prevent it from happening?
Anosognosia is a condition that happens unpredictably, so it’s not preventable. It also has to happen alongside other conditions or problems like stroke or schizophrenia. While some of these conditions are preventable, having them isn’t a guarantee that you’ll develop anosognosia.
It’s still a good idea to take care of and protect your brain. The best things you can do include:
- Eat a balanced diet and maintain a weight that's healthy for you. Many conditions related to your circulatory and heart health, especially stroke, can cause brain damage. Preventing stroke and similar conditions is a key way to reduce the risk of developing conditions that can lead to anosognosia.
- Don’t ignore infections. Eye and ear infections that spread to your brain can easily become serious or deadly. They can also cause brain damage that leads to conditions involving anosognosia.
- Wear safety equipment. Brain damage from head injuries can cause problems that also involve anosognosia. That means safety equipment, especially helmets, are essential both at work and during your off-hours.
- Manage your health conditions. It’s essential to manage conditions that can lead to or involve anosognosia, especially mental health conditions like schizophrenia. Managing those conditions can help you avoid serious complications or situations where an unmanaged condition becomes much worse.
Outlook / Prognosis
What can I expect if I have anosognosia?
The problem with this condition is that it keeps you from recognizing other illnesses. Because you can't recognize them, it's much harder to protect yourself from their effects. An example of this is how people with one-sided paralysis are much more at risk for fall injuries because they still think they can stand up.
How long does it last?
When it happens because of a lesion from an injury to your brain, it's more likely that anosognosia will get better on its own. While it may go away in some cases, it's also possible that it's permanent. Anosognosia is permanent when it happens with mental health conditions or degenerative brain disorders.
What is the outlook for this condition?
Anosognosia isn't fatal or dangerous on its own, but it increases your risk of complications from other problems. People with this condition are also more likely to resist or avoid medical treatment for the condition they can’t recognize.
How do I take care of myself?
If you have anosognosia, following your healthcare provider's guidance and advice is important. Relying on and trusting their expertise is essential because of your inability to see your health conditions. That includes seeing your provider as recommended, taking medications as prescribed and watching for any changes in your symptoms, especially ones you can't explain otherwise.
When should I see my healthcare provider?
Your healthcare provider will recommend a schedule of appointments for follow-up and ongoing care. It’s important that you see your healthcare provider as recommended. That way, they can help monitor your condition and recommend changes as needed.
When should I go to the ER?
Your healthcare provider can tell you the symptoms or changes that mean you need immediate medical care. They're the best source of information regarding the specifics of your conditions and circumstances.
A note from Cleveland Clinic
Anosognosia is a condition that can be confusing and frightening. To others, it might seem like stubbornness or living in denial, when in reality, this condition affects a person’s ability to understand what’s happening to their own body. For people who have this condition, it’s important to build a trusting relationship with your healthcare provider and to rely on their expertise. If you or a loved one has anosognosia, it’s also important to be as patient and understanding as possible. A strong support system and the help of loved ones can make a big difference with this condition, hopefully minimizing its effects on any other connected condition(s) and the health and well-being of everyone involved.
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