Memory, not a recording device
I remember growing up knowing that events in life were recorded in my mind. When I say recorded, I mean recorded as in the way songs or movies are recorded. You can pull a song up on your phone, play it and the song plays exactly the same every time. I thought that is how memories were stored in my mind. Many would like to think the memories stored in our minds are static and permanent, but that is not the case. This article discusses the memory process and types of memory.
Memory is a process that involves many stages. It’s hard to believe the process is so detailed and automatic. We don’t tell our minds to create memories; the mind just automatically does it for us. Some memories we are grateful to have and some memories we would like to forget. The purpose of memories is to help us live out day to day life. Life choices and decisions based on memories. An example is, “The last time I ordered salmon it was overcooked.” This memory will be pulled up and used the next time a menu choice is executed. Memories help guide our future decisions and behavior.
Most scientists agree there are four stages to memory. The first stage is termed encoding. Basically, an event is ‘experienced’ by you and your brain creates ‘traces’ assigned to that specific experience. Neurons in your brain are excited by what you are experiencing. Specific neurons responsible for your senses (sight, hear, feel, taste) are encoding what is happening creating traces. The brain gives preferential treatment to specific traces during encoding. Touching a hot pan will not only encode sensory information, but also the event will encode emotional and psychological aspects. Just know the more ways an event is encoded, the stronger the memory. It’s stronger because there are more traces attached to the event. The encoded elements (traces) are not organized at this point. The brain has just created elements (traces) that the mind has to organize. The organization of traces happens in the next step termed consolidation.
Consolidation must occur to transform a short-termed unorganized memory into a long-term organized memory. If an event (and its traces) is not consolidated, the traces will rapidly decay. During consolidation the brain modulates the strength of the encoded traces. Often, the consolidation process happens while you sleep. Picture the brain working like a crazy secretary filing all the traces in the brain. The ‘secretary’ is also creating a mapped index of what traces are needed to make up a particular memory. Consolidation stores a memory and enables memory persistence.
The third stage of memory is termed retrieval. When you recall a memory, you retrieve it from your mind. Retrieval happens in split seconds. During memory retrieval the brain reinstates and replicates the natural patterns that were present during encoding. The ‘secretary’ goes to the different parts of the brain and pulls all the traces necessary to recreate that specific memory. Now there are times when the wrong traces are pulled for recreation of a memory. Maybe the trace for a color was pulled from a different memory trace map. If the brain doesn’t correct the color trace it may change the memory by consolidating that wrong color trace file with that particular memory. Retrieval may happen when original neuron engagement occurs. This means that if you are standing in the same spot where a memory was created your mind may pull up that memory. This is why when you go to a park, you mind pulls all memories created at that park. Often detectives will take a victim to the scene of the crime for their statement, to engage memory reenactment.
The fourth stage is forgetting. A memory that could be recalled on an earlier occasion and unable to be currently recalled is termed forgetting. When a memory is no longer available it can be due to inability of the ‘secretary’ to find or compile the correct traces. If a memory is not accessible it means the file cannot be retrieved. The traces of the memory exist but the ‘secretary’ is on break at the moment or can’t figure out where the trace files are stored. Memories are forgotten because we don’t or haven’t required them to help us make decisions in current situations. We also can actively forget memories that we don’t want to remember. It is the brain’s natural tendency to degrade rather than preserve memories.
There are three types of memories. Semantic, episodic, and procedural. Semantic memories are factual knowledge, concepts, and meanings. They involve encyclopedia type information. Episodic memories are events in a person’s life. Examples are your wedding or a birthday party. Any event that has to do with your life is an episodic memory. A procedural memory is implicit in nature and usually involves a process. We don’t have to think about a memory to perform a task we are wanting to do. If we wish to write a quick note down, we don’t consciously think about all the steps involved in writing, we just write.
The more we retrieve a memory, the neural pathways are strengthened and less likely to be forgotten. Memories can be altered and changed when retrieved. Memories make us feel happy and sad. Most importantly, memories are used to help us make decisions in our lives. By-the-way, we actually don’t have secretaries in our mind. lol