Definition

Amnesia is the inability to remember information or events. It may be temporary or permanent.

Causes

The memory is created by complicated interactions with several parts of the brain. Most memory loss or the inability to make new memories is caused by damage to the brain. It may be caused by trauma, illness like brain infections, or some medications.

Sometimes the cause is not known, especially with transient global amnesia.

Rarely, a psychological trauma or shock can cause a type of amnesia called dissociative amnesia. This is most often short-term amnesia.

Risk Factors

Factors that may increase your risk of amnesia include:

• Head and brain injuries, such as from a car accident or contact sport
• Brain damage from conditions such as:
  • Alcoholism
  • Stroke
  • Severe illness affecting the brain, such as encephalitis
  • Illegal drug use, such as heroin
• Brain damage complications from procedures, such as:
  • Electroconvulsive therapy
  • Brain surgery
• Dementia, such as Alzheimer disease
• Recent physical or emotional pain or trauma
• Taking certain medications, such as anesthesia medications
• Metabolic changes, such as low blood sugar or hypoxia
• Migraine auras
• Seizures

Symptoms

Symptoms may include:

• Inability to remember past information (retrograde amnesia) and/or new information (anterograde amnesia)
• Confusion
• Disorientation

Amnesia generally doesn’t affect general intelligence, personality, or self-identity. In other words, people with amnesia remember who they are.

Diagnosis

You will be asked about your symptoms and medical history. The doctor will ask specific questions about memory loss and when it started. Family members may also be interviewed in order to gather information.

To help determine a cause the doctor may do the following tests:

• A physical and neurological exam
• Blood tests to look for chemical imbalances or infections
• Images of brain may be taken to look for damaged structures. Images may be taken with:
  • MRI scan
  • CT scan
  • Cerebral angiography
• Electroencephalogram—to test brain’s electrical activity

Treatment

Temporary amnesia will focus on treating the cause. This may include psychological treatment for dissociative amnesia. Some amnesia may only last a few days and will simply require observation until amnesia has passed.

Long-term amnesia will require occupational therapy and new skills to help manage daily activities. Occupational therapy can help with skills and use memory training to better manage memory loss. Technological tools, notebooks, or reminders like photos may also help manage memory gaps.

Memory loss can be difficult for the individual, family, and friends. A therapist or support group may help you and loved ones to adjust.

Prevention

There are no specific steps to prevent amnesia.

Family Doctor—American Academy of Family Physicians http://www.aan.com

Health Canada http://www.hc-sc.gc.ca

Amnesia treatment. Mayo Clinic website. Available at:
http://www.mayoclinic.org/diseases-conditions/amnesia/basics/treatment/con-20033182
Accessed February 6, 2015.

Memory loss (amnesia). NHS Choices website. Available at:
http://www.nhs.uk/conditions/memory-loss/Pages/Introduction.aspx
Updated January 22, 2013. Accessed February 2, 2015.

Treating amnesia. American Academy of Neurology website. Available at:
http://patients.aan.com/resources/neurologynow/?event=home.showArticle&id=ovid.com:/bib/ovftdb/01222928-200804040-00020
Published 2008. Accessed February 1, 2015.