I’m sure we all have a memory we would like to delete from our minds. Whether it be an overwhelmingly embarrassing moment, a tough breakup or a traumatic experience, we all can recall an event that we wish we could completely forget. Well, new research suggests that this may be soon possible to a certain extent, but with the gradual growth of studies in this particular topic, researchers argue that there will soon exist a rather effective method of memory erasure to free ourselves from mental burdens. In this article, I plan on discussing a few methods that researchers have taken in order to come to this conclusion, as well as to evaluate whether deleting memories is beneficial for humans.
Before we get into the whole theory behind how memories can be deleted, it might be good to first know how memories are formed. So, I will first give you a short and simple biology lesson on neuroscience. Please bear with me; I will do my best to make it as simple as possible.
In our bodies, we have a thing called neurons. They are elongated-looking cells with a nucleus, dendrites, axon and myelin sheath (see picture below). Neurons are responsible for the transmission of neurotransmitters, which are chemicals that relay information between cells. When a trigger, known as a stimulus, hits a particular neuron, it results in an exchange of potassium ions (K+) and calcium ions (Na+) across the cell surface membrane of the neuron along its axon. Once the potential difference across the membrane reaches the threshold, a reaction is stimulated. The difference in concentration of ions results in the opening of ion channels in the membrane of the axon, which in turn causes neurotransmitters to be released into the synaptic cleft – the gap between two neurons – so they can diffuse across it in order to reach the receptor of the dendrite of the following neuron. This transfer of neurotransmitters is how information is carried across neurons.
Any experience (stimuli) you go through is converted into electrical energy that is carried down your neurons. This experience is stored in your short term memory, which can hold up roughly seven to eight bits of information and, if not consciously repeated or continuously thought of, you are only capable of recalling this information for a time period of a few seconds to a few minutes. However, memories can be ‘transferred’ into your long term memory, which is found in the part of your brain called the hippocampus. Neurons work very methodically, and the more they communicate through the transfer of neurotransmitters, the more efficient this communication becomes. When you continuously recall particular information, the neurons continuously transfer the neurotransmitter acetylcholine across synapses, causing memories to become stronger and resulting in short term memories becoming long term memories in a process called long-term potentiation. Furthermore, your hippocampus is capable of differentiating memories and thus it stores them in different ‘compartments’ depending on what triggers it – whether it is a scent, activities, photos, etc. Your brain does this series of steps through what we call an implicit process – recalling and storing information that you are not actively thinking about. In short: long term memories are created through the repeated activation of two neurons, and therefore they can also become weaker if they are not reactivated frequently.
Now that we – hopefully – have the basics of memory storage down, let’s get into the research of ‘deleting’ memories. Several different studies have been conducted on this topic, but here I will focus and briefly discuss two of them: one which focuses on inhibiting the protein kinase M (PKM) in snails and one that focuses on using blood pressure pills whilst recalling traumatic experiences.
The overproduction of proteins in the brain can lead to the development of painful memories in neurons, which researchers argue can be genetically removed without hurting other memories. UCLA biologists conducted an experiment with the marine snail Aplysia, where they would give five mild electric shocks every twenty minutes, and repeat the process 24 hours later. This allowed them to measure their response time. Initially, the contractions would only last a second, but as the prodding continued, the contractions increased to 50 seconds. This showed that the snails had transferred the memory of the electric shock from their short term memory into their long term memory, and thus researchers inserted an inhibitor protein that would inhibit the receptors of the kinase protein. The results showed a drastic decrease in contraction time – back to 2 to 3 seconds – proving that the distressing experience associated with the electric shocks were efficiently erased from the snails’ memory. Researcher Daniel Glazman argues that this discovery could potentially lead to the amelioration of those who suffer from a post-traumatic stress disorder and Alzheimer’s disease. Obviously, there is a drastic difference between marine snails and complex human beings, but researchers are rather confident that these discoveries could lead to important advances in neurobiology.
The second study actually used human volunteers who declared they had a particularly painful memory they wished to forget. According to Dr Alain Brunet, a McGill University Professor, their patients were suffering from ‘adjustment disorder’. The study’s main goal was to help them deliberately forget the pain associated with a specific memory. Prior to the start of the experiment, the volunteers were asked to write a detailed script of the event they hoped to forget, and they would then read them out loud. Recalling information in this particular way ensures that the correct neurons are being fired up during the session. This procedure was done while under the influence of propanol, a blood pressure pill, over the course of six sessions. The pill was used to inhibit the specific receptors of the neurotransmitters in the brain which are linked to memory. At the end of the experiment, the researchers discovered that although the volunteers had not forgotten their chosen memory, they were capable of ‘erasing’ the emotional pain that came with it.
Researchers believe that the advances this kind of research has led to could be extremely helpful in assisting certain groups of patients. For the time being, the majority of the research is focused on helping those with a highly traumatic past. For instance, it could ameliorate the emotional fear of remembering particular events for war veterans, thus allowing them to willingly confront and deal with painful memories in order to overcome scarring experiences. It could also facilitate drug addicts in their battle to overcome their addictions by erasing the association of the high from their drug use.
On the other hand, the thought of being capable of deleting particular memories does raise some ethical questions. Some ethicists question if altering memories could lead to alterations in what it means to humans. Memories make up who we are, and such treatments could result in the deletion of important memories that are crucial to our character and personality. Regardless of the consequences of memory, every experience we have serves to teach us a lesson and prevent us from repeating our past mistakes. If we choose to forget those trivial moments of our lives, would we be able to avoid repeating certain mistakes? Additionally, the human brain is so complex and there is so much we do not yet understand about it that researchers would have to be awfully precise when targeting the specific neurons in order to ensure the deletion of the correct memory. There is always the possibility of erasing good memories; consider wishing to forget the pain of losing a loved one and accidentally erasing them from your memory completely, losing treasured memories.
Furthermore, there is the question of to whom this sort of treatment should be available. Professor John Harris from the University of Manchester introduces a relevant point of victims of violence, arguing that their wish to erase painful memories might meddle with “their ability to give evidence against assailants”. Moreover, he states that “[…] criminals and witnesses to crimes may, under the guise of erasing a painful memory, render themselves unable to give evidence.”
Although the main goal of the memory deletion/replacement research is well-intentioned, I must admit that I find it rather daunting and somewhat freaky. Personally, I most certainly would not feel like myself if I allowed a researcher to meddle with my memories, and I cannot even imagine how my life would change if I choose to delete one of them permanently. I realise that I am extremely fortunate to not have had any sort of traumatic experience in my life that I would consider forgetting about, but I believe that each experience we go through shapes our personality and the way we view the world. Painful memories encourage us to learn and grow as people and allow us to sympathise with those who have gone through similar situations. Erasing memories could most certainly lead to the repetition of past mistakes; you cannot learn a lesson if you forget what the lesson was about. Of course, I understand that researchers simply wish to discover a way to ameliorate the lives of those suffering and that they would be extremely selective of which patients could receive this treatment, but I do wonder what the consequences of forgetting certain memories so critical to human history – such as wartime – could be. Imagine that this treatment turns out to be exceptionally effective and largely available, and somehow humanity forgets about a critical event like World War II and somehow we do it all over again?
In spite of the fact that a memory meddling treatment could be beneficial in alleviating emotional distress for those with a disturbing past, I believe that learning to deal with these memories without messing with our neurons is still more effective in the long term. Learning to process, cope and overcome traumas is a process that every human being has to endure in order to mature, and I genuinely believe that this is supposed to be a difficult process in order for it to work – nothing truly good comes easily. Essentially, memories, regardless of good or bad, allow us to feel and connect with the environment around us and create strong bonds with others. More importantly, they shape who we are. I prefer to keep my painful memories where they are, safely stored away in my brain, because I believe that everything that has happened to me has benefitted me somehow and can be perceived as a learning opportunity.
Written by Laiana Farias
Oh yeah, I think all my memories make me, both good and bad, though I’m speaking of this as someone who hasn’t any trauma to carry around, so I might be biased. But this is an interesting note to know, which could be useful in my cyberpunk stories. Anyway, thanks for this post!