Amnesia is profound memory loss due to damage to the brain following injury, trauma or infection.
There are six different types of amnesia depending on the causes and the nature of disease progression.
- Anterograde amnesia: Here the person has trouble recollecting events after the onset of amnesia. Although the person's intelligence, personality and judgment is intact, his day-to-day functional memory is poor.
- Retrograde amnesia: here the person does not recall events that occurred before the onset of amnesia. The earliest memories are comparatively safe with memory decline building up to the event.
- Dissociative amnesia: This is a condition in which the patient is unable to remember vital personal information, and is in a trance-like state following witnessing a violent crime or a grave accident.
- Infantile amnesia: This is an inability to recall events from early childhood due to immaturity in certain areas of the brain in the very early stages.
- Transient Global Amnesia (TGA): This is temporary impairment in an otherwise healthy person's memory. Here the person is unable to recall recent occurrences, visuals or verbal information for more than a couple of minutes, and patients retain their identities, immediate recall abilities, distant memories, attention span, language function, visual-spatial and social skills. The period of memory loss does not usually last for more than a day, and individuals are able to remember what occurred during the period of memory loss.
- Wernike-Korsakoff’s Psychosis: This is a progressive disorder caused by extended alcohol abuse. It is usually accompanied by neurological dysfunctions such as loss of co-ordination during movement, or a feeling of numbness in the fingers and toes.
- Injury to the brain
- Ageing process
- Difficulty in recalling previously learnt information
- Difficulty in learning new things
Treatment depends on underlying cause.
- Appropriate medication
- Tender care
- Nutritional correction
- Abstinence from alcohol
- Wearing a helmet and seat belt to avoid injury
- Avoiding drunken driving
- Immediate medical attention in case of infection, stroke, brain aneurysm, or transient ischemic attack.