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Being able to erase bad memories and traumatic flashbacks could help in the treatment of a host of different mental health issues, and scientists have found a promising new approach to do just this: weakening negative memories by reactivating positive ones. In an experiment covering several days, an international team of researchers asked 37 participants to associate random words with negative images, before attempting to reprogram half of those associations and ‘interfere’ with the bad memories……Continue reading…..
By: David Nield
Source: ScienceAlert
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Critics:
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. People who are feeling distressed by unwanted traumatic memories, which they may constantly be “reliving” through nightmares or flashbacks may withdraw from family or their social circles in order to avoid exposing themselves to reminders of their traumatic memories.
Physical aggression, conflicts and moodiness cause dysfunction in relationships with families, spouse, children and significant others. In order to cope with their memories they often resort to substance abuse, drugs or alcohol in order to deal with anxiety. Depression, severe anxiety and fear commonly stem from traumatic memories. If symptoms of apathy, feeling of inability to control impulsive behavior, sleeplessness or irritability persist the person can discuss this with their family doctor or a psychotherapist.
Traumatic memories are formed after an experience that causes high levels of emotional arousal and the activation of stress hormones. These memories become consolidated, stable, and enduring long-term memories (LTMs) through the synthesis of proteins only a few hours after the initial experience. The release of the neurotransmitter Norepinephrine (Noradrenaline) plays a large role in consolidation of traumatic memory. Stimulation of beta-adrenergic receptors during arousal and stress strengthens memory consolidation.
Increased release of Norepinephrine inhibits the prefrontal cortex, which plays a role in emotion control as well as extinction or suppression of memory. Additionally, the release also serves to stimulate the amygdala which plays a key role in generating fear behaviors. Memory reconsolidation is a process of retrieving and altering a pre-existing long-term memory. Reconsolidation after retrieval can be used to strengthen existing memories and update or integrate new information.
This allows a memory to be dynamic and plastic in nature. Just like in consolidation of memory, reconsolidation, involves the synthesis of proteins. Inhibition of this protein synthesis directly before or after retrieval of a traumatic memory can disrupt expression of that memory. When a memory is reactivated it goes into a labile state, making it possible to treat patients with post-traumatic stress disorder or other similar anxiety based disorders.
This is done by reactivating a memory so that it causes the process of reconsolidation to begin. One source described the process this way: “[O]ld information is called to mind, modified with the help of drugs or behavioral interventions, and then re-stored with new information incorporated.” There are some serious ethical problems with this process as the reactivation of traumatic memories can be very harmful and in some cases cause anxiety attacks and extreme levels of stress.
Inhibition of reconsolidation is possible through pharmacological means. The administration of several different types of protein synthesis antagonists can be used to block protein synthesis that occurs after a traumatic memory is reactivated. The inhibition of creation of new proteins will stop the reconsolidation process and make the memory imperfect. The use of chemical agents as a means to alter traumatic memories has a basis in Molecular Consolidation Theory. Molecular Consolidation theory says that memory is created and solidified (or consolidated) by specific chemical reactions in the brain.
Initially, memories exist in a plastic, labile state before they are more solidly encoded. It has been argued that memory consolidation occurs more than once- each time a memory is recalled, it returns to a labile state. It states that things which cause memory loss after initial learning can also lead to memory loss after reactivation or retrieval and it is by applying a pharmacological intervention at this plastic point whereby a traumatic memory can be erased.
Exposure therapy involves gradually exposing individuals to a stimuli they find disturbing or fear inducing until it no longer provokes an emotional response. The stimuli can range from commonly feared situations and objects, such as heights or speaking publicly, to seemingly mundane objects and places that have become distressing through a traumatic experience. If someone is exposed to a traumatic experience it is common that being exposed to reminders, including memories, of the event will trigger anxiety attacks, emotional distress and flashbacks.
A common mechanism to deal with these potential triggers is to avoid thinking about them and to avoid situations where they may be exposed to them. This can affect quality of life by limiting where someone feels they can go and what a person feels comfortable doing. Evidence has been found linking early traumatic experiences with agoraphobia, an anxiety disorder where individuals fear having panic attacks outdoors.
By repeatedly and carefully having a patient think about or encounter the stimuli and confront the emotions they are feeling, they will experience less and less distress. By systematically targeting distressing memories and stimuli, with exposure therapy, it has been shown levels of depression and symptoms of PTSD decrease significantly. Virtual reality can be used to simulate the original conditions of a traumatic event for use in exposure therapy.
This is particularly useful when patients believe the memories of their experience are too strong for them to actively search for and retrieve. Virtual reality has been used to treat individuals with PTSD symptoms stemming from the terrorist attacks of 9/11.
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