In the last few years there has been an enormous growth in data storage technologies, we’ve progressed from the almost 30,000 USD a month leasable IBM 305 RAMAC, which weighed over a ton and could store less than 5 megabytes of data, to phones that can store 256 gigabytes and consumer hard drives that can store up to 10 terabytes. However, nothing can hold a candle to our brains data storage capacity, it’s insanely fast, compact, efficient and is reported to be able to store over 2.5 petabytes, that’s 2.5 million gigabytes! Even more impressive is that it has the ability to automatically remove memories from its storage that are no longer in use which means that the 2.5 petabytes probably stretches a lot further than we can even fathom. By now you are probably asking yourself, if I have this much available memory then why can I sometimes have such a hard time remembering stuff? The short answer to that is that encoding a memory is a fairly complex process that is affected by a host of different factors. If that answer doesn’t satisfy you then read on because we are going to explore that question in a lot more depth!
In order to fully understand human memory we first need to have a good grasp of some basic neuroscience, such as neuron structure and neurotransmission. At its most elementary our brains operate on a rapid conversion of chemical signals to electrical signals, which are then converted back to chemical signals. This process occurs at mind-boggling speeds and makes up the basics of neurotransmission, which is pictured below.
During neurotransmission, an electrical signal reaches the neuron, which results in a change of electrical gradient within the neuron; this is called an action potential. This allows little pockets called vesicles, which are filled with neurotransmitters; to dock onto the cell membrane of the neuron and release their neurotransmitters into a fluid filled space called the synaptic cleft. Once in the synaptic cleft, the neurotransmitters can bind to receptors on another neuron, which then generates an electrical signal within that neuron, and the process of neurotransmission repeats itself. However, in reality this process is much more complex since the change in electrical gradient is caused by an influx and efflux of various ions such as sodium, potassium and calcium, which can all exert unique effects within the neuron. In terms of memory, calcium is very important because it drives a process called long term potentiation (LTP), which is one of the main ways in which memories get encoded into long-term storage.
As can be seen in the image above there are two distinct types of receptors, metabotropic receptors and ionotropic receptors. In order to keep things simple we are just going to focus on the ionotropic receptors for now, which upon activation by a chemical signal, opens up its ion pore, which allows ions to flow in and out of the neuron. When it comes to memory, the activation of ionotropic NMDA receptors by the excitatory amino acid neurotransmitter glutamate causes calcium to flow into the neuron; the calcium then activates a protein within the neuron called calmodulin that sets into motion a large signalling cascade. The end result of this signalling cascade is an insertion of an AMPA receptor into the neuron, which also gets activated by glutamate but at a much faster rate then the NMDA receptor. The AMPA receptors then serve two purposes within the neuron, the first being that activation of the AMPA receptor, which occurs much more readily then activation of the NMDA receptor, sensitizes the NMDA receptor so that it too can become activated much more readily. This allows for a faster insertion of additional AMPA receptors. Secondly, since AMPA receptors get activated quicker, they are excellent for strengthening the connection between different neurons. The connection between these neurons is what makes up the basis of a memory. Think of this process as a friendships, most friendships start from nothing but then can develop into very strong friendships where there is a lot of transfer of information between the two friends, however, to maintain this friendship we must put in the effort to stay in contact with each other. If we fail to do this then a friendship can dissolve, which results in decreased transfer of information between the friends. Memory works in a similar manner, the more attention that is paid to a neuron, the more AMPA receptors will be inserted and the more transfer of information there will be from one neuron to the other. However, if no attention is paid to this neuron then there is no point in keeping these additional AMPA receptors around, when this happens another process is set into motion called long term depression (LTD) which removes the additional AMPA receptors and essential makes us “forget” a memory. So now that we know the basics of LTP and LTD we can use this knowledge to develop a regimen for ourselves that aims to improve memory encoding.
Strengthening The Connection
To start with the single best way to improve memory, is repetition and that is because memory encoding is a repetitive process. The more repeated stimulation the NMDA receptor receives, the more repeated insertion of AMPA receptors occurs and the stronger the memory becomes. To achieve this we need to alter the way we memorize things because it is simply very hard for a memory to last for a long stretch of time when we only make one attempt at encoding the memory. For example, lets try to memorize a phone number. If we see a phone number once, the majority of us will be able to remember it for a few seconds, that is because we briefly open up a memory trace, the beginnings of LTP, but if we do not engage with this memory trace LTD will kick in, to briskly remove the weak memory trace. Now if we look at the number a few times in the span of a few hours then we can slowly but surely strengthen the memory trace and allow it to consolidate into our long term memory, of course this sounds pretty straightforward but it is often overlooked when we try to memorize much more complex information. For example when we are studying for a physics exam, we need to first form a good memory of the theoretical aspects and then we need to intertwine that holistic memory with specific memories of formulas and how to use them. The mistake that is often made is that this material is cram studied in a rush, which only gives us a few hours of encoding time. Instead we need multiple days of encoding time full of repetitions to truly consolidate such complex information. However, we don’t always have the luxury of engaging in frequent repetition and thus we can help this process along a little bit with the help of some strategic nootropics. The most effective nootropics to aid memory either sensitize the AMPA receptor allowing them to be activated even more readily or sensitize the NMDA receptor which in turn leads to the insertion of more AMPA receptors. The most effective AMPA receptor sensitizers are the racetams like Oxiracetam, which is a little bit stimulating or Unifiram, which is one of the strongest AMPA sensitizing nootropic around. Nootropics that work on the acetylcholine system sensitize the NMDA receptor; this includes things like the acetylcholine precursors Citicoline and Alpha-GPC, and Huperzine A that prevents the breakdown of acetylcholine. Furthermore, it is important to get enough sleep and to keep stress levels down to a minimum, since sleep deprivation and stress can hamper memory formations significantly. If you need help controlling sleep and stress then the amino acid L-Theanine does a great job at minimising the impacts of stress and allows for higher quality sleep.