Visual Agnosia
Visual agnosia is a condition that affects how your brain processes what you see. Your vision works correctly, but your brain doesn’t. This affects how you recognize objects, people, places and more. This issue usually happens because of injuries or diseases of the brain. It’s often permanent, but therapy can help people adapt to this condition.
What is visual agnosia?
Visual agnosia is a condition that disrupts your brain’s ability to process and understand what you see with your eyes. There are several different forms of visual agnosia, with a wide range of effects on your ability to see the world around you.
Who does it affect?
Visual agnosia can happen to people at any age but happens more commonly with certain health conditions. Many — but not all — of these conditions are more likely to happen as you age. An example of an age-related condition that can cause this is stroke, while a brain injury would be an example of a cause that’s not age-related.
How common is this condition?
Visual agnosia (and all agnosias) is rare. However, there’s little available data within the last 50 years on how frequently people receive a diagnosis of visual agnosia.
How does this condition affect my body?
Your eyes allow you to see, but they only pick up visible light from the world around you. They then send nerve signals to your brain containing information about what they saw. Your brain turns those signals into information that you can understand and use.
Visual agnosia is when your eyesight works correctly, but the parts of your brain that process information from your eyes aren’t working as they should.
What are the symptoms of visual agnosia?
The symptoms of visual agnosias depend on the form and type of agnosias.
Forms of visual agnosia
TypeDefinition| Akinetopsia | This is when you can recognize objects but can’t recognize that they’re moving. |
| Alexia | People with this condition can’t recognize words they see. That means they can see the words but can’t make sense of or read them. They can still write and speak without any problem. |
| Amusia | The visual effect of this problem causes a person to lose the ability to read music (see the auditory effect below). |
| Autopagnosia | People with this type have trouble recognizing body parts, either their own or on another person. They might also have trouble recognizing body parts from a drawing or picture. A sub-type of this is finger agnosia, which means you know what fingers are, but can’t recognize them when you see them. |
| Achromatopsia | Also known as color agnosia, this is where a person can see colors and tell them apart, but they can’t identify the color. |
| Balint syndrome | This condition affects your ability to see the world around you. Instead of seeing the big picture and the details, including different objects and how they’re connected or related, you see only scattered objects. You also can’t connect how they relate to each other. |
| Cortical blindness | This happens when there’s damage to the parts of your brain that receive visual input. Your eyes work, but your brain can’t process the signals sent from your eyes. |
| Environmental agnosia | This type means you can’t recognize where you are, describe a familiar location or give directions to it. Topographical agnosia is a type of environmental agnosia. People with this problem can remember the specifics of a building layout or their surroundings but can’t recognize where they are in relation to that layout. This means they can’t find their way around. |
| Form agnosia | This is where you can see the parts of an object but can’t recognize the object itself. An example of this is identifying the wheels, seat and handlebars of a bicycle when you look at each part, but you can’t recognize them as part of the whole bicycle. |
| Simultanagnosia | Problems seeing more than one of an object. There are multiple types of this condition. Dorsal simultanagnosia: This is where a person can only see one object at a time. When they aren’t focusing on an object, they can’t see it. Ventral simultanagnosia: This is where a person can see multiple objects at a time but can only identify them individually. This is like standing in a forest but only recognizing one tree at a time and never recognizing the forest as a whole. |
| Prosopagnosia | Known as “face-blindness,” a person with this struggles to recognize the faces of people they’ve met before or facial expressions in general. This type of agnosia has apperceptive and associative forms: Apperceptive prosopagnosia is when you can’t recognize a person’s facial expressions or other nonverbal cues. Associative prosopagnosia is when you can’t recognize a person’s face even if you’re familiar with them. You can still recognize them by other means, such as their voice or the sound of how they walk. This condition usually happens because of brain damage, but it also has a congenital form, meaning you have it when you’re born. People born with this struggle to recognize faces their whole lives. Congenital prosopagnosia may be an inherited condition, as it sometimes runs in families, but more research is necessary to confirm this. |
| Social-emotional agnosia | This is when you can’t recognize nonverbal cues (like body language). It’s similar to apperceptive prosopagnosia (see directly above). |
What causes visual agnosia?
Visual agnosia happens because of brain damage or diseases that cause disruptions inside of your brain.
Brain damage
Damage to your brain causes injuries, known as lesions, affecting how those areas work. Some examples of conditions or problems that cause brain lesions include:
Brain tumors (including cancerous and noncancerous growths).
Head injuries such as traumatic brain injuries (TBIs).
Cerebral hypoxia (brain damage from lack of oxygen).
Infections (such as those that cause encephalitis).
Seizures and epilepsy.
Strokes.
Toxins, such as carbon monoxide poisoning.
Degenerative and progressive brain diseases
These are diseases that disrupt the structure or function of your brain, including the connections between different areas. Disruptions in the structure and connections mean that different areas of your brain can’t communicate and work together as they should.
Conditions that cause or involve these kinds of disruptions include:
Alzheimer’s disease.
Dementia.
Lewy body dementia.
Posterior cortical atrophy.
Is it contagious?
Visual agnosia isn’t contagious. While some infections can cause it, this is rare and having one of these infections isn’t a guarantee of developing this condition.
How is it diagnosed?
Diagnosing visual agnosia usually involves a combination of physical and neurological exams, gathering information about a person’s history, and diagnostic and imaging tests. Multiple approaches are usually necessary because the tests and exams look for different things:
Sensory tests. These tests will make sure that the involved sensation in question works as it should and rule out any sensation-related problems or conditions.
Cognitive and mental status check. These tests ensure the problem isn't with the person’s thinking, focusing or problem-solving abilities.
Memory and familiarity tests. These tests will verify that the person doesn’t have a memory problem. They also make sure a person’s lack of recognition isn’t because of a lack of experience or familiarity with various objects or items.
Diagnostic and imaging tests. These tests look for structural abnormalities or signs of damage to the relevant part of the brain.
What tests will be done to diagnose this condition?
The following diagnostic and imaging tests are possible with visual agnosia:
Computerized tomography (CT) scan.
Electroencephalogram (EEG).
Evoked potentials test.
Magnetic resonance imaging (MRI).
Spinal tap (lumbar puncture).
Other tests are possible if visual agnosia has a confirmed or suspected cause, such as an infection or exposure to toxins. Your healthcare provider is the best person to answer any questions you have about tests that are possible in connection with these conditions.
How is it treated, and is there a cure?
Visual agnosia isn’t directly curable. However, some of the underlying causes of this condition are curable. That can sometimes help these conditions improve, but brain damage often has permanent residual effects. If that’s the case, visual agnosia often doesn’t improve.
What medications or treatments are used?
The treatments and medications likely for visual agnosia depend on the goal. Some methods aim to treat or cure the underlying condition that caused visual agnosia. The goals of other treatments and therapies are to help a person adapt to and live with visual agnosia, especially when it’s likely that the condition will be long-term or permanent.
Treatments for causes of visual agnosia
These approaches work on the underlying problem that’s causing visual agnosia. In some cases, treating or curing the underlying issue can help or fix visual agnosia. In other cases, the treatment aims to stop the underlying condition from worsening and causing more severe problems.
Possible treatments include, but aren’t limited to:
Medications: These range from antibiotics for infections to antidementia medications.
Surgery: Visual agnosia can happen when tumors, cysts or other growths press on certain areas of your brain. Removing the intruding tissue with surgery, when possible, can relieve the pressure and hopefully let that part of the brain function normally.
Treatments to help you adapt to visual agnosia
In cases where visual agnosia might improve over a long period or is permanent, some treatments and techniques can still help. Therapy and rehabilitation programs with specially trained staff and support are often part of the care plan for people with this condition.
These programs can help you adapt in multiple ways, such as:
Use your other senses. People with trouble recognizing faces (prosopagnosia) are often taught to identify people based on their voice or other context clues. People with visual agnosia for objects can learn to identify them by touch or sound.
Set up patterns of behavior. One way to help people find things they can’t easily identify by sight is always putting objects in the same place. Labeling items can also help.
Complications/side effects of the treatment
The possible complications or side effects of visual agnosia and the related treatments depend strongly on the type of visual agnosia and the treatments themselves. Your healthcare provider is the best person to answer any questions about what you might expect during treatment, recovery and ongoing care.
How can I take care of myself or manage symptoms?
It's important not to self-diagnose or treat visual agnosia without seeing your healthcare professional. That’s because this condition involves changes in your brain, many of which can happen because of serious or deadly medical conditions. Many of the conditions that can cause visual agnosia also worsen over time, so it’s best to get care sooner rather than later.
How soon after treatment will I feel better?
Your healthcare provider is the best person to tell you what you can and should expect during your recovery. That’s because the recovery time for this ranges widely. Some people may recover over a few months to a year. Others will have this condition for the rest of their lives.
How can I prevent this condition from happening to me or reduce my risk of developing it?
Most conditions that cause visual agnosia happen unpredictably, or they happen for reasons outside of your control. Because of this, it’s not usually a preventable condition. The only way to prevent or reduce your risk of developing visual agnosia is to avoid or prevent some of the conditions and problems that cause it. Some of the most helpful things you can do include:
Eat a balanced diet and maintain a healthy weight. Heart and circulatory conditions like stroke can damage areas of your brain. Preventing stroke and similar conditions is one way to prevent visual agnosia or reduce your risk of developing it.
Don’t ignore infections. Don’t wait to get treatment for eye and ear infections. When these infections spread to your brain, they can cause serious or even deadly effects. They can also cause damage that leads to visual agnosia.
Wear safety equipment. Head injuries are a major cause of brain damage, including damage that leads to visual agnosia. Make safety equipment a priority whether you’re using it at work or on your own time.
Manage your health conditions. Several chronic conditions, such as epilepsy or sleep apnea, can cause brain damage. When you manage those conditions, you reduce the risk of damaging your brain in ways that could cause visual agnosia.
What can I expect if I have this condition?
Most people with this condition can expect difficulty identifying objects, people, places, etc. The specific problem depends on the form and type of this condition that you have. Your healthcare provider is the best source of information on what to expect with this condition and can tailor that information to your specific condition and circumstances.
How long does visual agnosia last?
Visual agnosia is almost always a long-term condition, lasting at least months. It’s also often permanent.
What’s the outlook for this condition?
While visual agnosia can be a disruptive condition, it’s not dangerous on its own. However, this condition often happens alongside or because of dangerous or life-threatening conditions. Because of this, monitoring this condition and getting care quickly if you develop it are essential to your long-term health and well-being.
How do I take care of myself?
Your healthcare provider is the best person to guide you on living with any kind of visual agnosia. They can also direct you to resources, programs and trained, experienced healthcare providers to help you adapt to and live with this condition. They can also track your symptoms and monitor any changes in the condition.
Mental healthcare
Many people experience anxiety or even shame because of this condition. Many will start to avoid situations and circumstances where their issue might become apparent. Counseling and therapy are also a good idea for people who experience these feelings. They can help you learn to cope with and manage your feelings and worries concerning your condition.
When should I see my healthcare provider?
If you start noticing the symptoms of visual agnosia, or if you notice a loved one showing any of them, it’s important to talk to a healthcare provider sooner rather than later (especially if the symptoms appear over a shorter period).
once you’ve got a diagnosis, your healthcare provider can set up a schedule of visits and care. You should also talk to them if you notice any changes in your symptoms or if your symptoms start to interfere with your usual routine and activities.
When should I go to ER?
If symptoms of visual agnosia appear suddenly, it’s important to seek emergency medical care. This is especially true if they happen in connection with hitting your head, which could indicate bleeding in your brain, or if they happen along with any symptoms of a stroke.
The symptoms of stroke include:
Weakness, numbness or paralysis on one side of your body.
Slurred or garbled speech.
Droop on one side of the face or vision loss in one eye.
Trouble swallowing.
Confusion, irritability or agitation.
Trouble focusing, thinking or remembering.
Sudden headache that’s severe or keeps you from going about your usual activities.
Visual agnosia is a rare condition that isn’t dangerous on its own. However, it can happen alongside serious medical conditions. Even when it doesn’t happen with dangerous medical conditions, it’s still a confusing, frightening medical problem. Fortunately, advances in medicine’s understanding of how your brain works have brought big improvements to how healthcare providers diagnose and treat this condition. Even if this condition is permanent, there are programs and healthcare providers who can help you adapt to it, so it has the least possible impact on how you want to live your life.