What Is Amnesia?

Amnesia—also called amnestic syndrome—can make it hard to recall details from the past or form memories of new events in the present. It is a severe memory illness caused by disease, brain damage, or certain drugs.

Though the problem can prevent you from recalling certain memories, it rarely compromises your knowledge of your own name. It is also unlikely to affect your knowledge of how to perform bodily functions like speech or daily tasks like dressing.

The problem can have short-term or long-term effects. Treatment depends on the cause of the problem. Amnesia occurs as a symptom of a larger issue. Treating that issue may improve recall if it is linked to a medical illness or mental health problem. Some cases may get better with therapy.

This article describes amnesia symptoms, causes, diagnosis, and treatment.

Types of Amnesia

There are several different types of amnesia. They are typically defined by the type of memory loss they cause, which can include different portions of past and future experiences, information, and learning. The kind of amnesia you have depends on several factors such as the cause of the condition and the events that occurred at the time the problem began.

Amnesia is a general class of memory loss that includes the following categories:

• Anterograde amnesia: Causes problems with short-term memory. The condition results in an impaired ability to learn and remember new information. It makes you unable to form new memories even though you may be able to remember an experience that occurred in the past.
• Retrograde amnesia: Causes problems with long-term memory. It interferes with your ability to retrieve information you learned or experienced before the onset of amnesia.

It is possible to have both anterograde and retrograde amnesia simultaneously.

Other types of amnesia can affect specific ways that you process memories of previous and/or new experiences and learning. These categories include the following:

• Dissociative amnesia: A rare dissociative disorder in which you are unable to remember key elements of your identity and life. It causes retrograde amnesia related to autobiographical memory. It usually follows a period of severe trauma or psychological stress.
• Post-traumatic amnesia: Memory loss that occurs after a brain injury, such as a stroke, head trauma, or coma. It can cause you to feel disoriented and have notable confusion regarding who you are, where you are, and what happened to cause your brain injury.
• Transient global amnesia: Occurs as a sudden and brief loss of memory, often in middle-aged or elderly people. It is a temporary condition that usually lasts between one and 10 hours. During that time, you are unable to make new memories, but you usually retain your memory of your identity, the identity of family members, and your ability to perform daily tasks. Physical symptoms like headaches, nausea, or dizziness may accompany these episodes.
• Drug-induced amnesia: Can occur as a result of taking certain drugs during prescribed treatment, general anesthesia, or substance abuse. It is usually temporary, though the incidents that occurred during the period that the drug affected you may be difficult or impossible to recall.

Amnesia Symptoms

The way you experience amnesia depends on the cause of the condition. Symptoms may appear gradually or suddenly. They may cause problems lasting from a few hours to the rest of your life.

Symptoms of amnesia can involve loss of memory of one or more of the following aspects:

• Personal autobiographical information and other details that define your identity
• Past events, information, education, or circumstances
• A specific period preceding the onset of amnesia
• An entire lifetime of experiences
• Any experience or information that occurred after the start of amnesia, causing an inability to make new memories

The following symptoms may also accompany amnesia:

• Confusion
• Confabulation, or the creation of false memories to replace lost memories
• Tremors or other uncoordinated movements that occur with neurological problems
• Disorientation

Causes

Amnesia occurs when disease or other types of damage affect areas of the brain that it needs for memory processing. Treating the underlying cause of amnesia can sometimes improve or restore the ability to recall and/or establish new memories.

The following are possible causes of amnesia:

• Brain injury from a car crash or other type of blunt force
  
• Stroke, brain tumor, dementia, or other types of brain disease
• Encephalitis or other types of brain infection
• Hypoxia, ischemia, carbon monoxide poisoning, or other types of oxygen deprivation
• Alcohol abuse
• Medications, drug abuse, or general anesthesia
• Wernicke encephalopathy (thiamine deficiency)
• Emotional trauma as a result of a disturbing event or experience
  

Diagnosis

Your healthcare provider reaches a diagnosis of amnesia by ruling out other neurological or psychological problems that may be the source of your memory loss. Some of the tools used most often in diagnosing amnesia include the following:

• Physical exam: Includes a neurological function test, including an assessment of reflexes, strength, balance, vision, hearing, gait (walking), motor strength, and control.
• Medical history: Your healthcare provider will ask questions regarding your medical history, the nature of your memory loss, when it began, and whether other symptoms have accompanied your symptoms of amnesia.
• Cognitive exam: Can include tests of logic, reasoning, judgment, and short- and long-term memory. You may take one or more tests based on your symptoms.
• Laboratory tests: Blood tests like a complete blood count (CBC) can identify signs of blood chemistry abnormalities, such as vitamin deficiencies and drug abuse that may cause amnesia.
• Electroencephalogram (EEG): Detects abnormal brain function by monitoring your brain's electrical activity and identifying seizures.
• Imaging tests: Magnetic resonance imaging (MRI) and computed tomography (CT) scans can help your healthcare provider identify problems like brain bleeding, brain tumors, inflammation, and brain damage.
• Lumbar puncture: Also called a spinal tap, examines the cerebrospinal fluid surrounding your brain and spinal cord. The results can help to identify a brain infection.

Treatment

The type of amnesia determines the treatment you receive for your symptoms. If your symptoms are caused by an underlying medical condition, you will have to get an accurate diagnosis and appropriate treatment for that problem before your memory issues can improve.

Though there is no cure for amnesia, you may be able to improve symptoms or restore your ability to recall and make new memories with one of the following therapies based on the cause of your amnesia:

• Occupational therapy to recover lost memories, build new memories, and counter ongoing memory loss
• Dietary supplements for amnesia caused by a thiamin deficiency
• Memory aids to help you function normally
• Psychotherapy to identify and cope with traumatic sources of amnesia
• Cognitive behavioral therapy (CBT) to help you develop strategies to counter harmful behaviors and thoughts
• Hypnosis to help you recover lost memories and prevent ongoing memory loss
• Meditation and alternative therapies to relieve stress
• Medication to treat underlying conditions or symptoms of anxiety or depression that may occur with amnesia
  

Prognosis

If you are diagnosed with amnesia, your prognosis depends on the cause of your condition. Amnesia occurs as a symptom of another illness. Depending on the cause of your amnesia, it may be related to a condition that affects your quality of life. overall well-being, or longevity.

The prognosis for amnesia varies by individual. Some types of amnesia may last only a few hours or days. For most people, lost memories return without treatment. However, other types of amnesia may last for years or cause permanent memory loss.

Your healthcare provider can provide specific details about your prognosis and its long-term impact on your ability to recall and form memories.

Coping

Coping with amnesia can be challenging and frustrating. If you have symptoms of amnesia or have a family member who has this condition, the following strategies can help you cope with this condition:

• Pursue treatment options recommended by your healthcare provider.
• Ensure that your living environment is safe and supportive to avoid feeling overwhelmed or stressed, which can interfere with your recovery from memory loss.
• Use technology and other tools to help you create reminders, stay organized, and help your daily life run as smoothly as possible despite your memory problems.
• Take advantage of offers from family and friends who are willing to provide support.
• Seek out an online or in-person support group to connect with others who are dealing with challenges similar to those you face.

Summary

Amnesia refers to varied types of memory loss that prevent you from recalling past details or forming new memories. The problem can result from disease, brain damage, or certain drugs.

Amnesia can cause symptoms that last hours, days, or longer. No one treatment works for all cases. When underlying issues are treated, the result can often restore your power to recall and/or form new memories. Therapy can often help improve symptoms.