Amnesia is often portrayed in the movies or on television as a temporary condition that has an easy fix. In fiction, amnesia tends to reverse itself and/or disappear after a period of time. When this happens, everybody cheers and life goes on as it did before.
But in real life, this is often not the case. While some people might recover and gain most, if not all, of their memories back, there are many people who do not. Even those who do recover from the condition that caused their amnesia may find things very different post-injury than how they were before.
There are different types of amnesia a person can suffer. One type is called anterograde amnesia. Those who suffer this condition are not able to form new memories.
What is Anterograde Amnesia?
As one of several classifications of memory loss, anterograde amnesia affects short-term memory. What happens is a person can’t remember new information he or she is presented with and, as a result, he or she is unable to establish new memories. People who are affected by it can remember their pasts prior to acquiring this type of amnesia, but they cannot remember anything that happens post-affliction; no information transitions from the short-term to long-term memory bank.
People living with anterograde amnesia are unable to form new memories as their memory banks are usually stopped at a specific time in their lives. Anything that takes place beyond this point is not transitioned to long-term memory.
How is Anterograde Amnesia Acquired?
In many cases, this type of amnesia is brought on by trauma to the brain, such as a blow to the head. It may also be drug induced; for instance, benzodiazepines have been linked to anterograde amnesia. 1 Another cause could be from brain surgery if the hippocampus or medial temporal lobe are injured. In rare instances it can be caused by emotional disorders or shock. 3
How Does Anterograde Amnesia Affect Daily Life?
A person living with anterograde amnesia will revert, daily, back to the time where he or she has full memories stored, very similar to the movie “50 first dates” starring Drew Barrymore and Adam Sandler. This movie is said to be loosely based on a true story, the one of a woman named Michelle Philpots.
Philpots lives in the United Kingdom and is a case that has been well-publicized. She has suffered from anterograde amnesia for more than 25 years. She suffered two separate incidents of traumatic brain injury (TBI) which were brought on by vehicular accidents. She was first injured in 1985 due to a motorcycle accident; the second TBI happened in a car crash five years later. 2
Initially, she suffered seizures, but over time her memory started to erode as well. Currently, Philpots is unable to recall any experience she had after the year 1994. As an example, she remembers Bill Clinton serving as president of the United States, but she can’t remember her marriage in 1997 to Ian, a man she was dating before being affected by anterograde amnesia. She remembers Ian and their dating years (she has known him since 1985), but she does not remember getting married to him. Other challenges she faces is her inability to finish a book, complete a task or, realistically, finish any project that isn’t short-term because the anterograde amnesia will interrupt what she’s doing or working on mid-task. A 2005 surgery helped with the seizures, but her memory issues persist.
In another case, a British soldier, identified as “William”, was stationed in Germany during the year 2005 went to the dentist for a root canal. He was administered a local anesthetic and can’t remember anything since. His short-term memories last about 90 minutes before they are wiped away, never to transition to his long-term memory bank. His past memories are fully intact, he wakes up each morning thinking he has a dentist appointment.
Doctors are unclear what caused his anterograde amnesia. It was theorized the anesthetic caused the memory loss; however William has no brain damage, which doctors say should be present. Other theories include it was triggered by his grandfather’s recent death or maybe was a genetic link to responses to stress. Experts have reportedly linked dental health to memory loss and cognitive function in studies.
“Although the link isn’t entirely clear, it suggests losing natural teeth may reduce sensory signals the teeth send to the brain, therefore affecting functions like memory. Natural teeth send signals to the brain via the nerve responsible for sensation in the face, and motor functions like biting and chewing”, writes Medical Daily in its July 2015 report. 4
It appears people suffering this condition experience some similarities, but every case is different.
Like other brain-related injuries, people with anterograde amnesia walk a different path - no two experiences are exactly alike.
No Two Anterograde Amnesia Cases are the Same
Much like any type of acquired head injury, no two types of amnesia are the same. How the anterograde amnesia is exhibited will depend on the area of the brain that was affected, not unlike the way symptoms occur after a traumatic brain injury is experienced. Some people with amnesia will recover memory capacity as they progress in their recoveries post-trauma, but this doesn’t always happen. Sadly, for some people the healing never comes and they can’t establish memories associated with any new experiences or knowledge due to the memory “resetting” itself every day, always leading back to the same place in time. Those afflicted cannot build new memories on the old.
[ Related Reading: Ways Behavioral Functioning Can Be Impacted by TBI ]
As science and tech continue to progress with new tools and knowledge to build upon, hopefully more insight and cures can be developed to help those suffering from different types of brain injuries. Over the decades, much has been learned about the brain, but there is still a long way to go.