What Is Amnesia?
Amnesia is the loss of memories. These may be memories of events and experiences that happened in the past few seconds, in the past few days, or in the distant past. You may also be unable to recall new things after the event that caused your amnesia. Contrary to popular belief -- and many TV and movie plots -- you are unlikely to forget who you are.
Amnesia can be short or long-lasting, depending on the cause.
Amnesia vs. dementia
Alzheimer's disease and other forms of dementia can cause progressive memory loss -- amnesia that keeps getting worse -- but these conditions have other consequences that set them apart from other causes of amnesia. If you have dementia, you develop problems with language, judgment, and everyday skills that keep getting worse and make it harder and harder for you to function.
Types of Amnesia
There are several types of amnesia. The major forms include:
Retrograde amnesia. Having retrograde amnesia means you've lost your ability to recall events that happened just before the event that caused your amnesia. Usually, this affects recently made memories, not those from years ago.
Anterograde amnesia. If you have this type of amnesia, it means that you can’t remember new information since your amnesia. You can still recall information from before the event that caused the amnesia. This is more common than retrograde amnesia.
Transient global amnesia (TGA). This is a less common temporary form of amnesia that tends to combine retrograde and anterograde amnesia and last no more than 24 hours. It occurs mostly in middle-aged and older adults, often with no clear cause.
Amnesia is also sometimes described by an underlying cause. These are some examples:
Posttraumatic amnesia. This occurs after a significant injury to your head and can include anterograde amnesia, retrograde amnesia, or both.
Dissociative amnesia. This kind of amnesia is caused by mental stress or traumatic events, such as abuse, war experiences, or natural disasters. It involves forgetting specific events or periods of time. In some cases, it could mean forgetting most of your identity and life history. In rare cases, you may forget all or most of your personal information and travel away from home or take up a new identity. This is known as dissociative fugue.
Drug-induced amnesia. Certain drugs can trigger short-term amnesia or contribute to longer-term memory loss. These include benzodiazepines, which are drugs commonly used for anxiety and insomnia, and anticholinergic drugs, which include some older antihistamines, muscle relaxants, and drugs for urinary incontinence. Older adults can be especially at risk. Blackouts from drinking alcohol -- in which you can't remember what happened while you were drunk -- are a form of amnesia, too.
Infantile amnesia. This isn't a disorder.It's also known as childhood amnesia and just describes the fact that most adults can’t recall early childhood experiences. This may be because young children’s brains are still developing and can't store memories the way older brains do.
Amnesia Symptoms
Your exact symptoms will depend on the type of amnesia you have and its cause. All kinds of amnesia involve problems with memory, but they may show up in different ways, such as:
- Trouble remembering past events
- Not recognizing familiar faces
- Not recognizing familiar places
- Not knowing how to get to familiar places
- Not knowing where you are going or why
- Forgetting familiar names
- Forgetting about upcoming events you had planned
- Not knowing basic facts, like the month or the current president
- False memories -- seeming to recall things that aren't true or are misplaced in time
What Causes Amnesia?
Many parts of your brain are involved in memory. Injuries, diseases, or stressful experiences that affect your brain can also affect your memory.
Some possible causes of amnesia include:
- Stroke or mini-stroke (transient ischemic attack, or TIA)
- Encephalitis or brain inflammation, due to a viral infection, or an autoimmune reaction
- Not enough oxygen to your brain, which can happen because of a heart attack or respiratory distress
- A brain tumor in areas affecting memory
- A brain aneurysm, which is a bulging blood vessel that can rupture
- Alcohol, which can cause short-term blackouts as well as longer-term memory problems linked to poor absorption of vitamin B1 (Wernicke-Korsakoff syndrome)
- Some medications, including general anesthetics, as well as some drugs used for anxiety, poor sleep, allergies, and other conditions
- Seizures
- Alzheimer’s disease and other forms of dementia
- Other degenerative brain diseases like Parkinson's and multiple sclerosis
- Severe head injuries
- Complications of brain surgery
- Electroconvulsive therapy (ECT), a treatment used for severe depression and some other mental health conditions
- Toxins, like carbon monoxide and heavy metals
- Emotional stress, often linked to traumatic events
Diagnosis of Amnesia
Your doctor will take a detailed medical history and ask questions to understand your memory loss. A family member, friend, or caretaker may take part in the interview as well.
Some of the issues discussed may include:
- Any triggers such as surgery or head injury
- When the memory issues started
- Alcohol and drug use
- Family history
- History of cancer, depression, headaches, or seizures
Your doctor may do a physical exam and check your thinking skills and memory with some simple tests. This may include checking your recall of some current events, past events, and personal details. You might also be asked to repeat a list of words.
Your doctor may also order some tests. These include:
- MRIs or CT scans to check for brain damage
- Electroencephalogram (EEG) to check for seizures
- Spinal tap to check for brain infections
- Blood tests for thyroid hormones, vitamin and mineral levels, and signs of infection
Treatment of Amnesia
There is no specific treatment or cure for amnesia. In some cases, your amnesia may improve as your brain heals. In other cases, treatment of the condition that caused your amnesia will help restore your memory or slow down or prevent further loss.
Typically, treatment for amnesia involves learning skills to help you make up for your memory problem.
Occupational therapy. An occupational therapist can help you learn new information or to teach you strategies to organize information. This may make it easier for you to remember past or future events.
Technology. A smartphone or tablet may be useful to help with your everyday tasks. For example, you can program your phone to remind you about events. You can also use your devices to organize handwritten notes, photos, appointments, and other files.
Medications. The FDA has not approved of any drug treatment for amnesia. But there are medications aimed at some causes. If you have early Alzheimer's, for example, you might qualify for some medications to slow it down. If you have amnesia linked to psychological trauma, medications for anxiety or depression might help along with talk therapy. And if you have Wernicke-Korsakoff syndrome, caused by alcohol use, treatment may include shots or tablets of thiamine (vitamin B1) -- though the main treatment is stopping drinking.
Living With Amnesia
Whether your amnesia is temporary or long-lasting, there are things you can do to cope.
Basic memory aids like to-do lists and notes to yourself, along with automated reminders from your smart phone, may help a lot with daily life. And you might need more help than in the past from trusted friends and family members.
You may also want to talk with others going through the same thing. Ask your doctor if there's a support group for people with your kind of amnesia -- for example, for people who've had brain injuries or strokes.
If your amnesia is severe -- for example, if you have a degenerative brain disease and can no longer form new memories -- you may need fulltime assistance, either at home or in a residential care facility.
How to Prevent Amnesia
You can minimize your likelihood of a brain injury and amnesia by:
- Wearing a seatbelt when in a vehicle
- Wearing a helmet when cycling
- Getting treatment for infections quickly so they don't spread to your brain
- Limiting alcohol use
- Getting immediate medical treatment if you have symptoms that may be due to a stroke or brain aneurysm, such as face drooping, trouble speaking, one-sided numbness, severe headache, or paralysis.
You can also protect your memory with a healthy lifestyle. For example:
Stay mentally active. Make brain-stimulating activities a regular part of your life. For example, learn a musical instrument, do crossword puzzles, or read books.
Be physically active. Exercise helps blood flow throughout your body and to your brain. Go for at least 150 minutes of moderate activity, like briskly walking, or 75 minutes of vigorous activity, like jogging, per week.
Sleep well. Most adults need between 7 and 9 hours of sleep. Our brain processes and categorizes our memories while we sleep.
Organize your life. If you find that you often forget things, try to organize and automate as much of your routine as possible. This might mean de-cluttering your home, assigning an area for essentials like glasses and keys, and keeping a regular notebook or planner.
Eat healthfully. Choose more fruits, vegetables, low-fat proteins, and whole grains to make sure your brain gets essential nutrients.
See your doctor. If you have a medical condition, follow your doctor’s recommendations. If you’re concerned about memory loss affecting your ability to do daily activities, talk to your doctor.
Takeaways
Amnesia rarely looks like what you see in movies and TV -- a total loss of your memories and identity. But any time you lose the ability to remember past events or make new memories, it's important to figure out what's going on so you can get the right kind of help. With help from your health care team, friends and family, and some technological assistance, you can find ways to cope, even when amnesia has long-lasting effects.
Amnesia FAQs
How long does amnesia last?
It depends on the underlying cause. If you have one form, transient global amnesia, you lose the ability to form new memories and recall the recent past for less than 24 hours -- usually a lot less. If your memory loss lasts longer than that, you may still recover over time, with treatment of the condition that caused the problem -- especially if you only have problems recalling past events, not forming new memories. But if you have a condition that permanently damages your brain or effects how it works, memory loss is likely to be permeant.
Can memories come back after amnesia?
In some cases, yes, you can remember the things you forgot, if the amnesia resolves. But it depends on the cause and severity of the memory loss. For example, if you have a severe alcoholic blackout, memories don't form during the gap -- so they can't be retrieved.
Is amnesia a mental illness?
No, amnesia is not a mental illness, though it is sometimes a symptom of a mental health condition, such as severe psychological trauma. More often, it is linked to brain injuries and diseases.
Who suffers from amnesia?
Since amnesia is usually a result of brain injury or diseases, you are at higher risk if you've had brain surgery, a stroke, head injuries, or seizures, or if you misuse alcohol.
