Imagine being able to remember everything you have ever said or done. If you’re like me, I barely remember what I said two days ago let alone everything I’ve ever said. Though, I’m sure it would get rather annoying to our partners if that were the case. There are those rare individuals who have a gift (or curse) which is called “Highly Superior Autobiographical Memory” or HSAM for short. These individuals have the uncanny ability to remember more personal and emotional memories. Memories referred to as episodic memories.
Episodic memories are just that, memories that have personal meaning that are tied to emotion. The other type of memory is called semantic memory. Semantic memories are not tied to emotions, they’re just facts. So if I ask you, who was the first President of the United States? Or, what is the capital of the United Kingdom? There probably is not much if any emotional ties to these answer, yet you were able to remember them. This is your semantic memory. Don’t worry, there are semantic memory champions as well:
So, it seems as though you can’t have it both ways, but that you can at least practice really hard and become good at your semantic memory. But how does memory really work? There are two ways that we’ll talk about it, the first will be cognitive and the other will be more neuroscience.
Cognitive psychologist use the Modal Model of Memory, which follows a path from sensory input, to sensory memory, to working memory, and then into long-term memory (LTM). Working memory is sometimes referred to as “short-term memory” though that term is not used as much anymore. From working memory, it has three places to go, the memory can decay, it can move into long-term, or the individual has to keep the memory active through rehearsal. Working memory has a capacity though, it can hold 7 items (plus or minus 2) within. It also has a time limit which is roughly 30 seconds, though if you believe old Hollywood movies, it’s more like 5 minutes. Once the memory goes into LTM, cognitive psychology doesn’t go into how it is stored, just mainly into how it is retrieved. For this, we turn to a more neuroscience approach:
According to Neuroscientists, forming a LTM starts this chain of neurons connecting that otherwise don’t normally connect. The example used above is building a bridge between two areas that weren’t previously connected. So, let’s take the example of the rats, when the tone is played, they receive a shock. After the first time, neurons are being connected to tell the rat, this tone equals a shock. After it is done a few more times, the connection between the neurons is stronger (long-term potentiation) and the signal is able to travel quicker when recalled.
This is only at the cellular level and does not fully explain the entire purposes, but it goes far enough for our purposes in this post because there has been a study done recently that challenges this school of thought. Neuroscientists have recently found that memories may actually exists within the neurons themselves. The implications of this, if supported, has not only the potential of changing the way in which we think about memory, but it could mean hope for those suffering from illnesses like PTSD and Alzheimer’s.
For PTSD sufferers, this could potentially mean that we could do a “Sunshine of the Spotless Mind” and zap the neurons and get rid of the memories in which the individuals are having the problems with. For Alzheimer’s, this could mean that their memories are truly lost and that they could, with further research, regain some of the previously thought lost memories. The research is really still new and definitely needs further testing to gain any sort of support and I remain skeptical as one critic suggested that the “results were observed in the first 48 hours after treatment, a time when consolidation is still sensitive.” Consolidation refers to the process in which working short-term memory becomes long-term memories.
As this is the last post that I’ll probably be making on this blog, I leave you with this scene of Eternal Sunshine of the spotless Mind: