Amnestic Disorder​

Amnestic disorders are a group of disorders that involve loss of memories, loss of the ability to create new memories, or loss of the ability to learn new information. These disorders are characterized by problems with memory function. There are a variety of symptoms associated with amnestic disorders, as well as differences in the severity of symptoms.

Some people experience difficulty recalling events that happened or facts that they learned before the onset of the amnestic disorder. This type of amnesia is called retrograde amnesia. Other people experience the inability to learn new facts or retain new memories, which is called anterograde amnesia. 

People with amnestic disorders do not usually forget all of their personal history and their identity, although memory loss of this degree of severity does sometimes occur in rare instances of dissociative disorders.

Amnestic disorders are caused by structural or chemical damage to parts of the brain. Problems remembering previously learned information vary widely according to the location and severity of brain damage. The ability to learn and remember new information, however, is always affected in an amnestic disorder.

The two main types of amnestic disorders centre on whether or not the cause of the memory problems is known.

• Organic Amnesic Syndrome: this is diagnosed when there is a known physical cause of the memory problems.
  

• Unspecified Amnestic Disorder: this is diagnosed when the exact cause of the memory loss is not fully known.

Amnestic disorder can occur due to a general medical condition or due to head trauma, tumours, stroke, or cerebrovascular disease (that is, disease affecting the blood vessels in the brain). Another type of amnestic disorder known as substance-induced amnestic disorder can be caused by alcoholism, long-term heavy drug use, or exposure to such toxins as lead, mercury, carbon monoxide, and certain insecticides.​​

When to seek expert advise

If you or a loved one is facing out of the ordinary memory loss issues, seek help from your doctor working with the Section of Neurology at The Aga Khan University Hospital. You can safely and privately discuss your symptoms, gain advice and receive personalised treatment and care.