What are the symptoms of anterograde amnesia?
People with anterograde amnesia can’t form new memories. That means you forget something that just happened within a short period. For some, their memory may last a few minutes or so. Others might forget about something only seconds after it happens.
Some of the most likely symptoms include:
- Forgetting about conversations or events shortly after they happen, which can cause people to repeat questions or say the same thing many times.
- Forgetting the names and faces of people they met.
- Confusion or disorientation about the time, date, current events, etc.
- Headaches.
- Problems with related abilities, including the ability to speak, write, read, etc.
Other symptoms are possible, but these usually depend on what’s causing you to have anterograde amnesia.
What causes anterograde amnesia?
Anterograde amnesia can happen for many reasons. The following is a list of some of the most common conditions (with more information for some below).
- Alzheimer’s disease.
- Brain aneurysms.
- Brain tumors (including cancerous and noncancerous growths).
- Cerebral hypoxia (brain damage from lack of oxygen).
- Frontotemporal dementia.
- Epilepsy and seizures.
- Drugs and medications (especially certain sedatives and anesthetics; see “anesthesia” below).
- Head injuries such as concussions or traumatic brain injuries (TBIs).
- Infections (such as those that cause encephalitis, such as from the herpes simplex virus).
- Mental health conditions or concerns (see “dissociative amnesia” below).
- Stroke.
- Toxins, such as carbon monoxide poisoning.
- Transient global amnesia.
- Wernicke-Korsakoff syndrome.
Alzheimer’s disease, dementia and other degenerative brain diseases
Degenerative brain conditions like Alzheimer’s disease and frontotemporal dementia are the most common causes of anterograde amnesia. Memory loss is extremely common with these conditions because they happen when areas of your brain deteriorate and stop working. People with these conditions have trouble recalling past memories and forming new ones. Memory problems are usually an early sign of these conditions and worsen as these diseases progress and cause more areas of their brain to die off.
Anesthesia
Some medications can cause amnesia for a short period. A common use of these medications is for sedation and anesthesia, such as before a medical procedure or surgery. Anesthesia not only puts you into a deep sleep, but also causes amnesia by blocking your brain’s conversion of anything you experience into memory, which is unlikely but still possible even though you’re asleep.
Psychogenic and dissociative amnesia
In rare cases, people can develop amnesia because of a problem with their mind — which is the combination of memories, experiences, thoughts and emotions that make you who you are — rather than the brain itself. The name for this is psychogenic amnesia. It happens because your mind blocks memory formation rather than a medical condition or distinct problem in your brain. It's rare, and experts don't fully understand how and why it happens.
Dissociative amnesia is when you lose memories because your mind dissociates as a defense against extreme mental stress or trauma. In severe cases, people may dissociate so much — especially during a traumatic event, anxiety or panic attacks, or flashbacks — that they don’t form memories while the dissociation happens.
Transient global amnesia
This is a short-term form of amnesia that usually affects people between ages 50 and 70 for unknown reasons. Part of what makes it unusual is that the amnesia it causes is temporary. People with this condition will seem disoriented and can’t form new memories. Fortunately, the condition is short-lived and usually goes away within a few hours. In very rare cases, it can last up to 24 hours.
Wernicke-Korsakoff syndrome
Wernicke-Korsakoff syndrome is a condition that happens because of a severe vitamin deficiency. This is usually due to damage to the brain when a person isn’t getting or isn’t absorbing enough vitamin B1 (also known as thiamine/thiamin). This condition is also common with other medical conditions like alcohol misuse disorders and eating disorders, and conditions that make it hard for a person to absorb vitamins from food.
Is anterograde amnesia contagious?
Anterograde amnesia isn’t contagious. However, some infectious conditions — especially certain viruses — can cause encephalitis, an inflammation of your brain. That can lead to anterograde amnesia. But having these kinds of infections isn’t a guarantee that you’ll develop anterograde (or any other form of) amnesia.
