Retrograde Amnesia: Overview and More

Retrograde amnesia is the inability to remember past experiences. This type of amnesia is specifically characterized by the loss of information or memories acquired before the event that caused the amnesia.

This article will review the symptoms, causes, diagnoses, and treatment for people with retrograde amnesia.

Retrograde amnesia is one of the two main categories of amnesia. The other type of amnesia is anterograde amnesia.

Retrograde amnesia is the inability to remember past events or experiences. People with retrograde amnesia remember events today but may not remember memories that occurred before the event that caused the amnesia. Retrograde amnesia usually affects more recently stored memories than older memories.

Anterograde amnesia is the inability to form new memories. People with anterograde amnesia may remember details about their high school prom, for instance, but have difficulty remembering what they ate for lunch on the current day.

Types of Retrograde Amnesia

Depending on the patient's circumstances, there are subtypes of amnesia that can be categorized as retrograde amnesia, or manifest as both retrograde and anterograde amnesia.

The following are types of retrograde amnesia.

Dissociative Amnesia

Dissociative amnesia is a type of dissociative disorder that affects a person's awareness and perception of themselves. It is a result of extreme stress or other traumatic experiences. These stressful events cause a person to dissociate (experience a lack of continuity in thoughts or a disconnection) from their own lives.

Those with dissociative amnesia may suffer from memory loss in certain areas of their life. But in more severe cases of dissociative amnesia, a person may not remember their name, family members, or entire parts of their life history. In extreme circumstances, a person may even create a new personal identity.

Post-Traumatic Amnesia

Post-traumatic amnesia results from a brain injury such as a stroke, coma (a state of prolonged unconsciousness), or head trauma.

Patients with this type of amnesia may not remember the event that caused their amnesia. It may also leave them disoriented in relation to time, place, and who they are.

Infantile Amnesia

Infantile amnesia is the inability to remember your first few years of life as a baby and toddler.

Transient Global Amnesia

Transient global amnesia (TGA) is sudden and temporary memory loss that usually only lasts from one to 10 hours. People who experience TGA typically know who they and their family members are, but they may not know where they are or what they are doing.

Transient global amnesia is also a type of anterograde amnesia because it prevents a person from forming new memories during the event. However, it can also have a short-term retrograde effect that usually lasts less than 24 hours. The cause is unknown.

Symptoms

The main symptom of retrograde amnesia is memory loss of past events. The symptoms of retrograde amnesia depend primarily on the type of amnesia occurring and can vary significantly from a few days to weeks or even from years to decades.

Causes

Some of the main causes of memory loss include injuries, illnesses, and stressful events.

Dissociative amnesia stems from extremely stressful circumstances or events in a person's life that cause them to dissociate.

Post-traumatic amnesia results from a brain injury such as a stroke, coma, or other head trauma.

Many researchers believe that infantile amnesia occurs due to the underdevelopment of the infant's brain.

Researchers are unclear of the cause of transient global amnesia. Some have suggested that other psychological disorders, venous flow abnormalities (problems with blood flow), or epilepsy may be to blame.

Other causes of retrograde amnesia may include:

• Alzheimer's disease
• Encephalitis (brain inflammation)
• Electroconvulsive therapy
• Head injuries
• Huntington's disease
• Multiple sclerosis
• Parkinson's disease
• Epilepsy
• Wernickes encephalopathy
• Cardiac arrest
• Anoxia (lack of oxygen)
  

Diagnosis

To diagnose retrograde amnesia, you will need to make an appointment with your healthcare provider. They will assess your memory by talking to you, observing how you recall past information, and maybe even talking to your family members about your communication at home.

You may have a neuropsychological evaluation, which is a more formal type of memory testing.

You may also have a physical examination and additional testing to look for the sources of the memory loss, such as:

• Blood tests
• Imaging tests, such as magnetic resonance imaging (MRI) or computed tomography (CT) scan to check for brain issues
• An electroencephalogram (EEG) to check for seizure activity
• A lumbar puncture (spinal tap) to check for a brain infection
  

Treatment

There are no known effective treatments or medications for retrograde amnesia. The priority usually involves treating the cause of amnesia.

For example, receiving therapy for amnesia caused by extreme stress may be helpful to recover some memories over time.

But for Alzheimer's disease or other degenerative illnesses, there is no available cure. However, medications are available that can slow the progression of Alzheimer's disease, which may also slow the progression of memory loss.

Some patients who have retrograde amnesia find that family support or participating in support groups can help with the frustration of memory loss.

Prognosis

Prognosis depends significantly on the source that is causing the amnesia. In some cases, memory loss is brief, only lasting for days or weeks. But for others, memory loss can last for years or even be permanent. Some memory loss may even get worse over time.

If you or a loved one is struggling with retrograde amnesia, talk with your healthcare provider about your prognosis and treatment options that may help you.

Coping

Many patients with retrograde amnesia struggle to understand what has happened to them. Much of the research emphasizes the benefits of having a solid support system, working with specialists or therapists, or experimenting with other treatments that help to stimulate the mind.

You may want to consider joining a support group with people who have had a similar experience as you. Talk with your healthcare providers about coping techniques that may help you with your specific cause of retrograde amnesia.

Summary

Retrograde amnesia is the inability to recall or remember past experiences. Several factors can contribute to this, including emotional or physical trauma, infections, dementia, head trauma, or other medical conditions. Memory loss can be temporary, long-lasting, or even permanent. Your healthcare provider will need to run several noninvasive diagnostic tests to diagnose retrograde amnesia.

A Word From Verywell

Retrograde amnesia can be a frustrating experience that causes confusion and stress. Because there are so many underlying causes, coping and recovery is a unique experience for everyone. In many cases, memory loss from retrograde amnesia takes time to recover from, and sometimes memory may not return at all. If you or a loved one is suffering from retrograde amnesia, talk to your healthcare provider about options that can help you.