Authored by Tahani Nsouli
Post-traumatic stress disorder (PTSD)
Definition: A mental health condition that's triggered by a terrifying event — either experiencing it or witnessing it. Symptoms may include flashbacks, nightmares and severe anxiety, as well as uncontrollable thoughts about the event.
Hippocampus
A region of the brain that is associated primarily with memory. The hippocampus, which is located in the inner (medial) region of the temporal lobe, forms part of the limbic system, which is particularly important in regulating emotional responses. Therefore, the hippocampus plays a role in emotional processing, including anxiety and avoidance behaviors. The hippocampus is principally involved in storing long-term memories and in making those memories resistant to forgetting, hence transferring them to long-term storage in our brains. It is also thought to play an important role in spatial processing and navigation.
Amygdala
The amygdala, another part of the limbic system is a small almond-shaped structure located deep within the temporal lobe of the brain. It plays a crucial role in processing emotions, particularly fear and anxiety. The amygdala plays a crucial role in threat detection and activating the body's fight-or-flight response. Apart from fear and anxiety, it is also engaged in various emotional functions such as pleasure, decision-making, and the acquisition of emotional knowledge. Moreover, it links emotions to memories and sensory inputs.
The Relation Between PTSD and your memory
The human brain possesses a built-in alarm system designed to safeguard our survival. However, individuals with PTSD experience an exaggerated sensitivity in this system, causing it to activate easily. Consequently, the regions responsible for cognition and memory in the brain do not function properly. As a result, distinguishing between current safe events and past traumatic events becomes challenging.
Over the past 4 decades, scientific methods of “neuroimaging” have enabled scientists to observe how PTSD causes distinct biological changes in your brain. While the symptoms and brain changes associated with PTSD can vary among individuals, there are observable patterns that can be comprehended and treated.
The hippocampus can be compared to the memory storage system of a computer, writing files into its hard drive. Following a traumatic experience, the hippocampus strives to accurately recall and comprehend the event. However, due to the overwhelming nature of trauma, the encoding of information may be disrupted. Consequently, individuals tend to struggle in remembering essentials details or find themselves excessively preoccupied with the experience as the hippocampus works tirelessly to make sense of the situation. In several studies, the severity of trauma and memory impairments showed a correlation with reduced hippocampal volumes. Stress, as well as depression (being common in individuals with PTSD), are associated with reduced dendritic branching throughout the hippocampus.
Similarly, traumatized youths showed reduction of amygdala volume with increase in PTSD symptom severity. The amygdala serves as the catalyst for your innate alarm system. Upon experiencing a disturbing event, it transmits a signal initiating a fear response. This response is crucial for ensuring your safety when the alarm is appropriately activated, hence at the right time and for the right reason: to keep you safe. However, individuals with PTSD tend to have an overly sensitive alarm system, so something as harmless as a car backfiring could instantly trigger panic. The amygdala represents a primitive, instinctual part of your brain that’s wired to ensure survival. So when it’s overactive, it’s hard to think rationally. Therefore, reduced hippocampal and amygdala volume is remarked as a PTSD characteristic.
Conclusion
PTSD greatly affects memory processes and memory consolidation, leading to memory disruption and heightened sensitivity to trauma-related cues. These memory disturbances make it challenging to distinguish between past traumatic experiences and current safe events. Needless to say, it’s crucial to understand the impact of PTSD on memory in aims of developing effective interventions and support systems to alleviate the negative effects on memory function, and enhance the overall well-being of individuals affected by this condition.
Work Cited
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