Amnesia is when you have significant memory loss. There are many possible causes of it. Sometimes it’s a symptom of other conditions, but it can also happen on its own. It can involve past memories, or you can have trouble making and storing new memories. Treating the underlying cause may reverse it, but some causes are permanent.
Amnesia is when you have serious memory loss. It can be a symptom of other conditions or happen by itself.
Amnesia comes from ancient Greek and means, “forgetfulness.” But it’s more than that. Forgetfulness is misplacing your keys or not remembering to do something while running errands. Amnesia involves being unable to remember significant events or details from your life.
There are two main forms of amnesia. Retrograde amnesia is when you can’t recall memories from your past. Anterograde amnesia is when you can’t form new memories but can still remember things from before you developed this amnesia.
Other forms of amnesia include:
Amnesia is uncommon on its own. But it’s a very common symptom of certain conditions. These conditions usually involve brain damage or activity disruptions. An example is Alzheimer’s disease, a major cause of amnesia. About 24 million people worldwide have Alzheimer’s, which accounts for millions of people with amnesia. And there are dozens of other possible causes.
Symptoms of amnesia depend on the type you have.
You might experience:
People with amnesia may also experience something called confabulation. This is when your brain automatically tries to fill in memory details and makes a mistake. An example of confabulation would be misremembering what day an event happened on recently, or the details of an event from your past.
People who have confabulation believe their memory is genuine and accurate. They don’t intend to lie or deceive. It’s just an error that happens without their knowledge. Ordinarily, confabulation is harmless. But it can become a bigger issue and may be something you notice when memory loss is more severe.
Amnesia can happen for many reasons. The causes fall broadly into two main categories: neurological causes and psychological causes.
Neurological causes of amnesia all involve damage to your brain or disruptions in brain activity. The possible causes include (but aren’t limited to) the following:
Memory loss can also happen in connection with mental health issues. Examples include dissociative disorders, especially dissociative amnesia, and post-traumatic stress disorder (especially complex PTSD). These cases usually involve a traumatic event, or severe mental or emotional distress. Experts don’t fully understand why it happens, but they suspect it’s your brain’s way of trying to limit or protect you from psychological harm.
A healthcare provider can usually diagnose amnesia by talking to you and asking questions about yourself, your life, current events and your symptoms. There are also diagnostic tests and imaging scans that can contribute to the diagnosis. The tests that your provider recommends will vary depending on what they suspect is causing your amnesia and if you have other symptoms.
Several tests can contribute to diagnosing a condition that causes amnesia or rule out other conditions that might cause it. Imaging scans are among the most common but aren’t the only useful tool.
Possible tests include:
There’s no direct treatment or medication that can cure amnesia. When it happens because of a treatable condition, treating that condition is the best way to reverse it. Because many conditions can cause amnesia, the treatments can vary widely, too. Many times, your brain can recover on its own, and you’ll regain your memory as it does.
People with amnesia may not understand what’s happening to them. They might not be able to make informed choices about their medical care. In those cases, a loved one with the authority to do so may need to make decisions for them.
Cognitive rehabilitation and occupational therapy may also help some with memory loss. These types of therapies can teach you skills and techniques to help you compensate for any loss of memory or related abilities. Rehabilitation and therapy can also help loved ones learn how to support you best.
Some causes of amnesia are preventable, but amnesia itself isn’t predictable. People can have a condition that causes it but never develop amnesia as a symptom. Amnesia can also happen for reasons that are completely out of your control.
But you can take some steps to reduce the risk of amnesia happening:
If you have amnesia, you may not be aware of it immediately. Most people who have it feel disoriented early on. You might also have trouble making sense of the experience because you don’t remember or understand what caused your amnesia. What you can expect may also depend on any other symptoms you have.
In general, your healthcare provider (or your loved one’s provider) is the best person to tell you more about what you can expect. The information they provide will be the most accurate and relevant for your specific case.
When amnesia affects how you form or store memories (anterograde amnesia), that kind of memory loss is permanent. Amnesia that affects how you retrieve memories (retrograde amnesia) may improve over time, depending on what caused it in the first place.
Memory loss is more likely to be permanent when it happens because of conditions that permanently damage your brain or disrupt how it works (like Alzheimer’s disease). Because this can vary, your healthcare provider (or your loved one’s provider) is the best person to tell you what’s most likely in your situation.
People with amnesia can often compensate for their memory loss in multiple ways. Some use lists and notes to compensate or use smartphone apps or other forms of technology. Family, friends and loved ones may also help by supporting your efforts to regain your memories (if and when it’s possible) and recover from whatever caused your amnesia.
People with amnesia from degenerative brain diseases or who have anterograde amnesia (and can’t form or store new memories) usually need support or medical care 24/7 (like with family members or in a skilled nursing facility).
If you have memory loss that begins and develops slowly, you might not be able to recognize it in yourself. It’s more likely that a loved one will notice it first. If you notice it in yourself, asking for help is a good idea. Everyone needs support at some point, and there’s no shame in admitting that you need it.
Often, a loved one will be the first to notice signs of memory loss. If you notice it in someone you care about, they may not want to admit that something’s wrong or might not feel like that’s the case. If that happens, it’s best to do and keep the following in mind:
If a loved one needs more care and support than you can offer, don’t be afraid to look for alternatives or ask for help. Seeking long-term care options for a loved one might be the best way to keep them safe and maintain their quality of life.
Sudden memory loss in yourself or someone you’re with is always a sign to get medical attention. That’s the best, safest course of action regardless of whether there’s an obvious cause.
If you have any kind of memory loss after a head injury or an impact that might cause whiplash, you need medical attention immediately. Even if you don’t pass out, not remembering an injury right after it happens could be a sign of a concussion or traumatic brain injury.
If you notice possible signs of memory loss, you may want to ask your provider the following:
Amnesia rarely affects motor skills. When you learn how to do something, like swim or ride a bike, your brain stores memories of how to do it in a different part of your brain. That’s why amnesia doesn’t typically affect motor abilities or learned skills.
No, your memory lives in a different part of your brain than the areas that hold personality and behavior. While you can have damage to both, having damage to one area doesn’t automatically damage the other.
No, amnesia and mild cognitive impairment are separate. You can have both at the same time (like with degenerative brain diseases or head injuries), but they aren’t the same.
Alcohol can disrupt the formation of new memories, but you usually have to be significantly intoxicated for that to happen (the common term for this is a “blackout”). Binge drinking may increase the chances of this happening. The definition of binge drinking is a single session where you have five or more drinks (if you’re assigned male at birth or AMAB), or four or more drinks (if you’re assigned female at birth or AFAB).
Your memory is like your brain’s recording of important events or details about your life. Think about it like a library of what happened in your life. Creating that library involves the following steps:
Your brain has different memory formats depending on how long you need to store a memory. Those formats are:
Types of memory
You have different forms of memory, explicit (declarative) and implicit (nondeclarative). Amnesia only affects explicit memory.
A note from Cleveland Clinic
Your memory is a key part of who you are, so not being able to remember something can be a scary experience. If you’re experiencing memory loss or have a loved one showing signs of it, you should talk to a healthcare provider. Despite how it looks on TV or in movies, sudden memory loss isn’t common. And many of the conditions that cause memory loss are treatable. Your healthcare provider can help you better understand what could be causing memory loss, what you can do about it and how you can reduce its impact.
Last reviewed by a Cleveland Clinic medical professional on 09/25/2023.
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