The management of traumatic memories is important when treating mental health disorders such as post traumatic stress disorder. Traumatic memories can cause life problems even to individuals who do not meet the diagnostic criteria for a mental health disorder. They result from traumatic experiences, including natural disasters such as earthquakes and tsunamis; violent events such as kidnapping, terrorist attacks, war, domestic abuse and rape. Traumatic memories are naturally stressful in nature and emotionally overwhelm people's existing coping mechanisms.
When simple objects such as a photograph, or events such as a birthday party, bring traumatic memories to mind people often try to bar the unwanted experience from their minds so as to proceed with life, with varying degrees of success. The frequency of these reminders diminish over time for most people. There are strong individual differences in the rate at which the adjustment occurs. For some the number of intrusive memories diminish rapidly as the person adjusts to the situation, whereas for others intrusive memories may continue for decades with significant interference to their mental, physical and social well being.
Several psychotherapies have been developed that change, weaken, or prevent the formation of traumatic memories. Pharmacological methods for erasing traumatic memories are currently the subject of active research. The ability to erase specific traumatic memories, even if possible, would create additional problems and so would not necessarily benefit the individual.
Intense psychological stress caused by unwanted, troublesome memories can cause brain structures such as the amygdala, hippocampus and frontal cortex to become activated, as they process the memory. Related to this, there is some neuroimaging (fMRI) evidence that those who are susceptible to PTSD have a hippocampus with a reduced size. Research has also demonstrated the adrenal activity from intense stress dramatically increases activity in the amygdala and leads to changes in brain functioning as well as altering physiological indicators of stress; heart rate, blood pressure and an increase in salivary enzymes, all of which vary with individual responses to stress.
Children who have been exposed to traumatic events often display hippocampus-based learning and memory deficits. These children suffer academically and socially due to symptoms like fragmentation of memory, intrusive thoughts, dissociation and flashbacks, all of which may be related to hippocampal dysfunction.