Episodic and Semantic Memories

Episodic memories and semantic memories are different types of memories. The former refers to events we participated in and are capable of being something as extravagant  as one’s own wedding or high school graduation, but may also be as forgettable as what one ate for dinner two weeks ago on a Friday evening. To summarize, episodic memories are an autobiographical recollection of one’s own  experiences which did occur upon any place or time. Researchers theorize that these memories are held within a temporal manner inside the brain. They are, in general, facts about ourselves that we can recall.

Semantic memories are the opposite… They are facts about the world around us. General knowledge such as the sky is blue and 2 + 2 = 4, etc.

It is believed that in the medial temporal lobe is where the episodic memories are created and stored (within the hippocampus), but evidence also suggests that the pr-frontal cortex plays an important role as well, believed to be such because of experiments showing that when it is damaged, episodic memories are not created as easily.

It is not yet known for how long memories are stored within the hippocampus. Some say for forever, laying dormant, but others feel that the storage is only temporary and that they are erased to make room for new memories (with only the one’s of significance being stored forever). Notoriously, Alzheimer’s Disease, which  is known to erode memories, has been found to cause great damage to the hippocampus prior to damaging other parts of the brain. Alzheimer’s, which killed my own grandfather, eventually destroys all memories and makes the person a hollow shell of who they once were, before killing them off permanently.

Semantic memories tend to be about general facts that everyone remembers or should remember. They tend to be pertaining to general facts about society and the world and how things work, Such examples are what the capital of Spain is, or what a cell’s interior looks like, or that the sky is blue. They typically involve non-personal memories and do not require the individual to “travel back in time: to recall them like an episodic memory does. Both memories are LTM.

In my own life, it is not hard at all for me to recall many episodic memories. A few examples of such are my graduation from high school, the first time I moved out on my own, the first concert I attended, etc. I feel that with episodic memories, it is not hard to recall them and when they happened, but with semantic memories, it can be just as easy to recall or even more difficult. An example would be me absolutely hating math and not being able to recall those “general” facts about how to solve equations that every student has hammered into their heads in high school. I was the type of kid that would study and study for a math test for many hours, still not remembering much at all and on the day of the the test, I  would blank.

Semantic and episodic memories play such a vital role in our lives everyday and we do not even realize it.

 

Wede, J. (2017) Lesson 6: Episodic Memories. Retrieved from Lecture Notes Online Web site.

Wede, J. (2017) Lesson 6: Semantic Memories. Retrieved from Lecture Notes Online Web site.

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