Trauma

Trauma can impact four different types of memory. 

We have the explicit memory and the implicit memory.

The explicit memory consists of the semantic memory and the episodic memory.

The semantic memory is the memory of general knowledge and facts. We all remember what a bicycle is. 

But how trauma can affect the semantic memory? Well, trauma can prevent information (like words, images, sounds) from different parts of the brain from combining to make a semantic memory. The related brain area is the temporal lobe and inferior parietal cortex which collect information from different brain areas to create semantic memory. 

The episodic memory is the autobiographical memory of an event or experience-including the who, what, and where. For example, you remember who was there and what street you were on when you fell of your bicycle in front of a crowd. 

But how trauma can affect the episodic memory? Trauma can shutdown episodic memory and fragment the sequence of events. The related brain area is the hippocampus which is responsible for creating and recalling episodic memory.

The implicit memory consists of the emotional memory and the procedural memory.

The emotional memory is the memory of the emotions you felt during an experience. For example, when a wave of shame or anxiety grabs you the next time you see your bicycle after the big fall. 

How trauma can affect the emotional memory? After trauma, a person may get triggered and experience painful emotions, often without context. The related brain area is the amygdala which plays a key role in supporting memory for emotionally charged experiences. 

The procedural memory is the memory of how to perform a common task without actively thinking. For example, you can ride a bicycle automatically, without having to stop and recall how it is done. 

But how trauma can affect the procedural memory? Trauma can change patterns of procedural memory. For example, a person might tense up and unconsciously after their posture, which could lead to pain or even numbness.  The related brain area is the striatum which is associated with producing procedural memory and creating new habits.