What to Know About Amnesia

Amnesia is the loss of memories. These memories may be of events and experiences that happened in the past few seconds, in the past few days, or even in the distant past. You may also be unable to recall experiences after the event that caused your amnesia. 

Types of Amnesia

There are several different types of amnesia.

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 temporary form of amnesia that tends to resolve within 24 hours. It occurs more often in middle-aged and older adults. Once this type of amnesia resolves, it rarely recurs.

You may repeatedly ask the same question and have no recollection of the past few hours. Your memory will slowly return over the next 24 hours. Experts are unsure what causes this type of amnesia.

‌Post-traumatic amnesia. This occurs after a significant injury to your head and can present as either anterograde amnesia, retrograde amnesia, or both.‌

Infantile amnesia. Also known as childhood amnesia, this term is used to describe the way adults can’t recollect early childhood memories. This may be because young children’s brains are still developing and unable to consolidate memories.‌

Dissociative amnesia. Dissociative amnesia is caused by stress or trauma and presents as forgetting specific events or periods of time. In some cases, dissociative amnesia could even 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. 

Causes of Amnesia

Many parts of your brain are involved in memory. Injury or disease that affects your brain can also affect your memory. ‌

Some possible causes of amnesia include:

• Stroke
• Encephalitis or brain inflammation. This could be due to a viral infection, or an autoimmune reaction. 
• Not enough oxygen to your brain. For example, because of a heart attack or respiratory distress.
• A brain tumor
• Long-term alcohol abuse
• Some medications such as benzodiazepines (tranquilizers)
• Seizures
• Alzheimer’s disease and other forms of dementia
• Severe head injuries‌
• Emotional trauma 

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 run some cognitive tests. This may include asking you for some general information about current or past events, personal information, or repeating a list of words. 

Your doctor may also order some tests. These include:

• Magnetic resonance imaging (MRI) or computed tomography (CT) scan to check for any brain damage
• Electroencephalogram (EEG) to check for seizures
• Spinal tap to check for brain infections 
• Blood tests for thyroid hormones, vitamins B1 and B12‌

‌Additional symptoms. Depending on the type and cause of your amnesia, additional symptoms include disorientation, confusion, and false memories (either distortions of real memories or completely fabricated memories). 

Treatment of Amnesia

There is no specific treatment for amnesia. In some cases, your amnesia may improve as your brain heals.

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 may also find that technology helps organize handwritten notes, photos, appointments, and other files. ‌

Medications. The Food and Drug Administration has not yet approved of any drug treatment for amnesia.

How to Prevent Amnesia

You can minimize your likelihood of a brain injury by:

• Wearing a seatbelt when in a vehicle
• Wearing a helmet when cycling
• Getting treatment for infections quickly so that it doesn’t spread to your brain
• Limiting your consumption of alcohol
• Getting immediate medical treatment if you have symptoms that may be due to a stroke or brain aneurysm. This includes face drooping, trouble speaking, one-sided numbness, severe headache, or paralysis.‌

Some of these activities may be able to help you sharpen your memory.

• Stay mentally active. Make brain-stimulating activities a regular part of your life. For example, learning a musical instrument, doing crossword puzzles, or reading a book can all provide healthy mental stimulation.
• Be physically active. Any exercise is better than none because it helps blood flow throughout your body and to your brain. The Department of Health and Human Services recommends 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 doing some de-cluttering in your home, assigning an area for essentials like glasses and keys, or keeping a regular notebook or planner. 
• A healthy diet. Choose more fruits, vegetables, low-fat proteins, and whole grains to make sure your brain gets enough vitamins and minerals. Drug use and excessive alcohol can also lead to memory loss. 
• 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.