Memory is one of the most complex and fascinating abilities of the human mind. However, understanding why bad memories of the past are intermittently recalled or why our memory is deformed requires delving deeper into this complexity.
Basic mechanisms of memory
Memory works in three main stages: encoding, storage and retrieval.
- Encoding: New information enters our brain through sensory input and is processed here. The information is encoded by passing through the stages of sensory memory, short-term memory and long-term memory.
- Storage: Coded information is stored by the brain in various ways. Long-term memory is maintained in the cerebral cortex and hippocampus through various neural connections.
- Retrieval: It is the process of remembering stored information when necessary. In this process, our brain uses various cues and connections to bring back memories.
Traumatic memories and memory deformation
Traumatic events are a major source of stress for the brain and these events are often processed differently. The effects of trauma on memory are caused by several different factors:
Stress and brain chemistry: High levels of stress can disrupt the normal functioning of the brain. Stress hormones such as cortisol negatively affect the function of the hippocampus, making it difficult to encode and store information correctly.
Dissociation: During traumatic events, some people may experience a sense of detachment from reality. This can lead to intermittent recall of memories. Dissociation is recognised as the brain's mechanism to protect itself from the emotional burden of the trauma.
Cognitive processing: Traumatic memories are processed differently from normal memories. The brain processes such events more quickly and superficially, which can make it difficult to recall memories fully and in detail.
Scientific research and findings
Many scientific studies have examined the effects of trauma on memory. For example, a Harvard University study showed that traumatic memories are often fragmented and incomplete. By monitoring brain activity during the processing of traumatic memories, this study observed how stress hormones affect hippocampal function.
Similarly, a study at Stanford University examined how dissociation affects the storage of traumatic memories. The researchers found that dissociative experiences prevent memories from being recalled in a complete and chronological manner.
Neurobiology of memory disorders
Memory disorders are associated with dysfunctions in specific regions of the brain. Regions such as the hippocampus, amygdala and prefrontal cortex play critical roles in the encoding, storage and retrieval of memory. Dysfunctions in these regions during traumatic events can lead to deformation of memories.
Hippocampus: The hippocampus plays an important role in the encoding and storage of memory. High cortisol levels during trauma can impair the function of the hippocampus, preventing the full encoding of memories.
Amygdala: The amygdala plays an important role in processing emotional memories. During trauma, the amygdala becomes overly active, which can lead to emotionally charged and distorted recall of memories.
Prefrontal Cortex: The prefrontal cortex plays an important role in the recall and organisation of memories. Trauma can lead to dysfunctions in this area, resulting in intermittent recall of memories.
