Amnesia or Memory Loss
Head | Neurology | Amnesia or Memory Loss (Symptom)
Memory loss, also called amnesia, is a state characterized by an abnormal degree of forgetfulness and/or inability to remember past events.
Depending on the cause, memory loss can be permanent or temporary and memory loss may have a sudden or gradual incursion. Memory loss may be limited to the inability to recall recent events, events from the distant past, or a combination of both. Although the normal aging process can result in difficulty in learning and retaining new material, normal aging itself is not a cause of significant memory loss unless there is accompanying disease that is responsible for the memory loss.
The causes of amnesia have traditionally been divided into certain categories. Memory appears to be stored in several parts of the limbic system of the brain, and any condition that interferes with the function of this system can cause amnesia. Functional causes are psychological factors, such as mental disorder, post-traumatic stress or, in psychoanalytic terms, defense mechanisms. Amnesia may also appear as spontaneous episodes, in the case of transient global amnesia.
There are many types of amnesia. Post-traumatic amnesia usually occurs after a head injury, dissociative amnesia is due to a psychological cause and includes: repressed memory, dissociative fugue, post-hypnotic amnesia. Lacunar amnesia is the loss of memory about one particular event and childhood amnesia is the inability to remember events from one's own childhood. Source amnesia is a memory disorder in which someone can recall certain information, but they do not know where or how they obtained the information. Drug-induced amnesia is intentionally caused by injection of an amnesiac drug to help a patient forget surgery or medical procedures. Anterograde amnesia is the loss of long-term memory, the loss of the ability to form new memories through memorization. Retrograde amnesia, the loss of pre-existing memories targets the patient's most recent memories.
Diagnosis and Treatment
To diagnose amnesia, a doctor will do a comprehensive evaluation to rule out other possible causes of memory loss, such as Alzheimer's disease, other forms of dementia, depression or brain tumor. The physical examination may include a neurological exam to check reflexes, sensory function, balance, and other physiological aspects of the brain and nervous system