Understanding Amnesia: Possible Causes and Treatments

Amnesia is a loss of memory function. It can result from trauma, drug or alcohol use, medication, or a medical condition. Depending on the cause, amnesia can be temporary or permanent. No one remembers every event or life experience. Amnesia is an unusual deficit in remembering certain blocks of time.

You should see your clinician for signs of memory loss. These signs may present as difficulty with:

• remembering past events or activities you once knew
• remembering recent events or activities

You can also experience deficits in remembering both distant and recent past events. Your healthcare professional can evaluate your symptoms, attempt to find the underlying cause, and suggest a treatment plan.

This article presents a general overview of amnesia, including the different types, signs and symptoms, possible causes, and treatment options.

Amnesia is a term to describe impairment in forming new memories or recalling old ones. It occurs due to a specific cause, such as stroke. Amnesia is not the mild memory loss that can become more common with age, such as forgetting a name or misremembering a date.

Amnesia may be temporary and resolve after you address the underlying cause. Other times, amnesia may last longer or be permanent.

Amnesia is different from dementia because amnesia is a loss of memory. In contrast, dementia is a problem that also affects thinking, learning, and communication.

Amnesia is mainly a condition affecting the hippocampus in the brain. The hippocampus is a structure with two segments, one located in each temporal lobe. It takes in data from the senses and information from your experiences to create new memories.

Forgetfulness tends to increase as people age. Find out when to contact a doctor here.

The four main types of amnesia are summarized here.

Retrograde amnesia is the inability to recall information you successfully learned in the past. An example of retrograde amnesia is an inability to perform a task that you had previously performed routinely, such as sewing, woodworking, or navigating a neighborhood. People with retrograde amnesia do not remember things that happened before the onset of amnesia.

Anterograde amnesia is the inability to create or keep new memories. Existing memories are unchanged. For example, someone with alcohol intoxication may not recall the events of a given evening. However, they can remember things that happened before they began drinking.

Dissociative amnesia is frequently associated with trauma. It involves a feeling of disconnection from one’s memory, as though those memories belong to someone else.

Transient global amnesia is a sudden, short-term episode of anterograde amnesia, particularly associated with seizure activity. It lasts less than 24 hours and generally resolves on its own.

Infantile amnesia is the inability to remember events occurring in the first 3–5 years of life. This is typical of most people and not an amnestic disorder.

Behaviors and symptoms associated with amnesia may include but are not limited to the following:

• disorientation or confusion
• inability to recall information
• confabulation, which is when the brain constructs false memories to fill in gaps in memory
• changes in personality
• difficulty paying attention

A common cause of short-term amnesia is surgical anesthesia. You may forget the time immediately before surgery and right after the procedure as you fall asleep and wake up. This is typical and affects people of all ages regardless of their health status. However, the effects of anesthesia on memory are more pronounced in older than younger people, according to older studies and supported by a recent study.

The many other possible causes of amnesia include:

• medical conditions, such as:
  • Alzheimer’s disease
  • stroke
  • brain tumors
  • epilepsy, as nearly 50% of people with epilepsy have memory problems
  • brain infection
• side effects from medications, such as narcotics, sedatives, and tranquilizers
• substance use, including alcohol and illicit substances
• traumatic brain injury (TBI)
• anoxia, or a lack of oxygen to the brain
• medical procedures, such as brain surgeries or electroconvulsive therapy
• delirium due to fever or illness

You may be able to prevent amnesia by preventing or managing the conditions that lead to it. Prevention measures include:

• preventing TBI by:
  • wearing protective equipment, such as seatbelts and helmets
  • removing trip hazards, such as scatter rugs
  • installing handrails on stairs and grab bars in bathrooms, lowering the chance of slipping and potentially injuring your head
• lowering your chance of stroke with diet and regular blood pressure checks
• preventing drownings and near-drownings by securing water sources, such as pools and hot tubs, and using safety devices in or near natural bodies of water
• avoiding alcohol use
• avoiding substance use
• avoiding overuse or misuse of prescribed medications known to cause amnesia

Take a look at eight foods that help your brain here.

Diagnosing amnesia and the underlying cause requires a complete medical history, physical examination, and specific memory and cognitive tests. You should take someone with you to the appointment to help with an accurate assessment. The person accompanying you can also help you remember the information you receive at the appointment.

The clinician may ask you about the following items:

• your medication history
• drug and alcohol use history
• onset of symptoms, in general:
  • what you noticed first
  • how long you have had symptoms
  • what made you become concerned enough to seek medical care

Your doctor will perform a physical exam that will include memory testing, cognitive testing, and a neurological assessment.

Tests your clinician may order include the following:

• blood tests
• drug toxicity testing
• CT scan or MRI to assess for bleeding, tumors, or lesions
• electroencephalogram to assess your brain’s electrical activity

The treatment and management of amnesia will depend on the underlying cause and nature of the amnesia. There are no medications that can repair the brain to restore memory.

Doctors may prescribe medications for amnesia symptoms or target the condition causing amnesia. For example, opioid antidotes, such as naloxone, can help decrease the effect of opioid medications by reversing their activity in the brain.

If you or a loved one has amnesia, there are several ways to manage certain aspects of memory loss and live as independently as possible. Coping strategies for living with amnesia can include:

• Occupational therapy: Occupational therapists work with people to manage activities of daily living. A study in an inpatient rehabilitation facility shows that early intervention for skill retraining was effective for patients with severe TBIs.   
• Technology: You can use digital apps, calendars, and medication minders to manage your daily medication and event schedules. GPS tracking devices may help you avoid getting lost. Lifeline devices, which are wearable items that notify emergency services if necessary, can offer daily check-ins and medication reminders.
• Lifelogging: This is a technique in which patients with memory loss wear small cameras set to take photographs at specified intervals. One review of research shows that it offers excellent benefits for people with amnesia.
• Brain stimulating activities: It may be possible to preserve memory by keeping the brain engaged and active, according to the Food and Drug Administration (FDA) and other organizations. Challenging activities, such as games, puzzles, or writing, may strengthen brain cell interactions.
• Rest and patience: Rest, avoiding strenuous activities and stressful situations, and returning to work or school gradually may aid in healing TBIs. 
• Medications: Aricept (donepezil) is prescribed for people living with dementia. However, some research exists showing possible benefits in TBI and Parkinson’s-related memory loss.

Learn the benefits of sleep on memory function here.

Here are some other questions people often ask about amnesia.

Amnesia ranges from short-term to permanent. The duration of the amnesia depends on the cause and whether permanent brain damage has occurred.

Sometimes treating the underlying cause can cure amnesia.

You should contact your doctor about amnesia if your symptoms are new or you are not sure what causes them.

Read about how to exercise your brain here.

Amnesia is a loss of memory. It can be of short or long duration and occurs due to various conditions and circumstances. If you notice that you have symptoms of amnesia, it is important to see your physician for a thorough evaluation.