Amnesia: How to Detect It, Types, Symptoms, Causes, Diagnosis and Treatment

Clinical or psychological phenomenon?

It is when a person can no longer memorize or retrieve information that is stored in memory. It is very rare, despite being a popular subject for movies and books.

Being a little forgetful is completely different from having amnesia. It refers to a loss of large-scale memories that should not have been forgotten.

These can include important milestones in life, memorable events, key people in our lives and vital events that we have been told or taught.

Fast facts about amnesia

Here are some key points about amnesia:

  • Amnesia is the inability to establish new memories, remember old memories, or both.
  • Other symptoms of amnesia may include confusion and uncoordinated movements.
  • Alcohol abuse can lead to a type of amnesia known as Wernicke-Korsakoff psychosis.
  • Amnesia can be caused by many things, including traumatic experiences and brain injuries.
  • Amnesia usually resolves without treatment.

How to detect it?

Amnesia can be the result of a head injury.

People with amnesia also find it difficult to remember the past, memorize new information and imagine the future. This is because we build future scenarios based on our memories of past experiences.

Our ability to remember events and experiences involves a variety of complex brain processes. We still do not understand exactly what happens when we assign something to memory, or when we try to retrieve data stored in our brain.

Most people with amnesia are generally lucid and have a sense of self. However, they may experience serious difficulties learning new information, struggling to remember memories of past experiences, or both.


There are many different types of amnesia. Below is a list of the most common:

  • Antegrade amnesia: the person can not remember new information. The things that happened recently and the information that should be stored in the short-term memory disappear.

This usually results from a brain trauma, when a blow to the head causes brain damage, for example: The person will remember the data and events that happened before the injury.

  • Retrograde amnesia: in a way the opposite of antegrade amnesia, the person can not remember the events that occurred before their trauma, but remember what happened next. Rarely, both retrograde and antegrade amnesia may occur together.
  • Transient global amnesia: a temporary loss of all memory and, in severe cases, difficulty forming new memories. This is very rare and more likely in older adults with vascular disease (blood vessels).
  • Traumatic amnesia: memory loss is the result of a hard blow to the head, for example, in a car accident. The person may experience a brief loss of consciousness or a coma.

Amnesia is usually temporary, but the time it usually lasts depends on the severity of the injury. Amnesia can be an important indicator of concussion.

Wernicke-Korsakoff’s psychosis: Prolonged alcohol abuse can lead to progressive loss of memory that gets worse over time. The person may also have neurological problems, such as poor coordination and loss of sensation in the fingers and toes.

It can also be caused by malnutrition, specifically a deficiency of thiamine (vitamin B1).

  • Hysterical amnesia (fugue or dissociative): Rarely, a person can forget not only his past but also his identity. They may wake up and suddenly have no idea who they are.

Even if they look in the mirror, they do not recognize their own reflection. A driver’s license, credit card or ID card will not make sense. Usually, it is triggered by an event that the person’s mind can not handle properly.

The ability to remember usually comes back slowly or suddenly in a few days, but the memory of the shocking event may never come back completely.

  • Infantile amnesia (infantile amnesia): the person can not remember early childhood events, possible due to a problem of language development or some memory areas of the brain that do not fully mature during childhood.
  • Post-hypnotic amnesia: events during hypnosis can not be remembered.
  • Amnesia of the source: the person can remember certain information, but not how or where they got that information.
  • Blackout Phenomenon: An excessive drink of alcohol can leave a person with memory spaces, where he can not remember chunks of time during the drunken state.
  • Prosopamnesia: the person can not remember the faces. People can acquire it or be born with it.


The following are common symptoms of amnesia:

  • The ability to learn new information is affected in antegrade amnesia.
  • The ability to remember past events and previously familiar information is affected in retrograde amnesia.
  • False memories can be totally invented or consist of real memories lost in time, in a phenomenon known as confabulation.
  • Uncoordinated movements and tremors indicate neurological problems.
  • Confusion or disorientation may occur.
  • There may be problems with orthopedic term memory, partial or total memory loss.
  • The person may be unable to recognize faces or places.

Amnesia is different from dementia. Dementia includes memory loss, but it also involves other important cognitive problems that can affect the patient’s ability to carry out their daily activities.


Any disease or injury that affects the brain can interfere with memory. The memory function involves many different parts of the brain simultaneously.

Damage to the brain structures that make up the limbic system, such as the hippocampus and the thalamus, can lead to amnesia; The limbic system controls our emotions and memories. Medical Amnesia Amnesia as a result of brain injury or damage.

The possible causes are:

  • Cerebrovascular accident.
  • Encephalitis or inflammation of the brain due to a bacterial or viral infection or an autoimmune reaction.
  • Celiac disease may be related to amnesia, confusion and personality changes.
  •  Oxygen deprivation, resulting, for example, from a heart attack, respiratory distress, or carbon monoxide poisoning.
  • Some medications, such as sleeping medication.
  • Subarachnoid hemorrhage or bleeding in the area between the skull and brain, a brain tumor that affects a part of the brain involved in memory, some seizure disorders.
  • Electroconvulsive Therapy (ECT) or electroshock therapy. psychiatric treatment where seizures are induced by therapeutic effect, can lead to temporary memory.
  • Injuries, which can lead to memory loss that is usually temporary.

Psychological amnesia

Also known as dissociative amnesia, this is caused by emotional shock, such as:

  • A sexual violent crime or other abuse, such as a strong fight or act of aggression, which can cause any intolerable life situation, generating serious psychological stress and internal conflict can lead to a certain degree of amnesia.
  • It is more likely that psychological stressors interrupt personal and historical memories rather than interfering with the determination of new memories.


A doctor will have to rule out other possible causes of memory loss, such as dementia, Alzheimer’s disease, depression or a brain tumor.

They will take a detailed medical history, which can be difficult if the patient does not remember. Family members or caregivers may need to be present. The doctor will need the patient’s permission to discuss their medical details with another person.

Questions may include:

  • Can the patient remember events and recent events in the past?
  • When did the memory problems start?
  • How did they develop?
  • Could there be factors that have caused memory loss, such as a head injury, surgery or stroke?
  • Is there a family history of a neurological or psychiatric condition?
  • Does the person consume alcohol?
  • Are you using any medication?
  • Have they taken illegal drugs, such as cocaine or heroin?
  • Are the symptoms undermining your ability to take care of yourself?
  • Do they have a history of depression or seizures?
  • Have you ever had cancer?

A physical examination may include control of aspects of the brain and nervous system, such as function and reflex of sensory balance.

The doctor can also check the patient’s memory: judgments, short-term memory, long-term memory, This memory assessment will help determine the degree of memory loss.

These studies will help find the best treatment. To know if there is any physical damage or brain abnormality, the doctor can order and perform a Magnetic Resonance Imaging (MRI) or Electroencephalogram (EEG).

Blood tests can reveal the presence of any infection or nutritional deficiencies.


In most cases, amnesia resolves without treatment. However, if there is an underlying physical or mental disorder, it may be necessary to identify a treatment:

  • Psychotherapy can help some patients.
  • Hypnosis can be an effective way to remember memories that have been forgotten.
  • Family support is crucial.
  • Photographs, smells and music can help.

Treatment often involves techniques and strategies to help compensate for the memory problem. This may involve:

  • Work with an occupational therapist to acquire new information to replace lost memories, or use existing memories as a basis for acquiring new information.
  •  Learning strategies to organize information, to make it easier to store.
  • Use digital aids, such as smartphones, to help with daily tasks and remind patients of important events, when to take medications, and more.
  • A list of contacts with face photographs can be useful.

Currently there are no medications to restore lost memory due to amnesia. Malnutrition or Wernicke-Korsakoff syndrome may involve memory loss due to a deficiency of thiamine (vitamin B1), so specific nutrition can help.

Whole grains, legumes (beans and lentils), nuts, lean pork and yeast are sources rich in thiamine.