Q. How do i get rid of painful memories? It seems as if when a memory arises, if i don't "do" anything with it, am just present, it not only eventually recedes, but is somehow weakened - how does that work from a cognitive neuroscience basis?
A. An excellent Scientific American article in May gives some good insights on the neuroscience of how memories are formed and different approaches to deal with extremely painful ones, like Post Traumatic Stress Disorders (PTSDs), and to understand how to deal with painful memories that arise in meditation.
As shown in the graphic below (all graphics by Emily Cooper), memories are formed when the a stimulus activates the linkage from one neuron to a useful, functionally-related second neuron. As these neurons fire together, "Hebbian theory" operates, i.e. "neurons that fire together, wire together".
This theory, by Donald Hebb in 1949, relates to "plasticity" at the synapses between neurons. The efficiency of transmission across the synapse increases with "repeated and persistent" stimulation. The more times these neurons fire together, or in near "synchrony", the stronger this firing pattern becomes. Neuroscientists call this "long term potentiation" (LTP); we call it "memory".
Some complex chemistry at the synapses changes to stabilize the link to improve the ease of transmission. Usually it is unstable - forming, disappearing and reforming. A memory is formed with an enzyme which produces what is known as PKMzeta.
Not surprisingly, other chemicals can block the action of PKMzeta to prevent memories from forming, or if they formed, to remove them. ZIP is a potent chemical which wipes them out, all of them, like reformatting a hard drive. Not a good solution.
A better approach is to "interrupt" the process of consolidation, when a short term memory becomes a long term one. Memories "worth" being stored long term are accompanied by emotionally-significant events, which release the neurotransmitter norepinephrine. Norepinephrine promotes protein synthesis in the amygdala, which plays a primary role in the processing and memory of emotional reactions.
This interruption" process could be done, just as it was with PKMZeta and ZIP, with something that blocks norepinephrine. Propranolol, well known for treatment of hypertension, anxiety and panic, does that. As memories consolidate over a period of several hours after a traumatic event, if folk are given propranolol during this period, the memory would still be recalled but without the emotional trauma. It also works after a memory was recalled if propranolol was administered before the memory could be reconsolidated.
This would seem to be a solution for PTSD, however...personal-injury lawyers, prosecutors, and "bioethicists" have gotten involved, as has the federal government. The ability of propranolol to alter memory-based evidence and modify behavioral response to past traumatic experiences has some "legal and ethical complications". A seminal paper "Therapeutic Forgetting: The Legal and Ethical Implications of Memory Dampening" by Adam Kolber was published in the Vanderbilt Law Review. There is now a federal law forbidding researchers from approaching patients directly; permission must be obtained from a clinical caregiver, like a busy EMT, which has slowed research.
There are also the side/after effects of propranolol, linked to significant "adverse drug reactions" due to high penetration of the "blood/brain" barrier to cause major sleep disturbances such as insomnia, vidid dreams and nightmares as well as extensive neuropathic pain.
Given the problems with propranolol, a useful and likely successful approach is "replacement". In "replacement", during the reconsolidation period after a traumatic memory manifests, a new/modified memory is created, which replaces the original in long-term memory.
There is some excellent work in this area, which has much similarity to meditative practice approaches to pain and memory management. A recent, heavily cited paper is "Preventing the Return of Fear in Humans Using Reconsolidation Update Mechanisms" by Daniela Schiller, et al. @ NYU published in Nature in 2010.
A typical experiment is to condition subjects to expect a shock when they see a blue square on a monitor. "Replacement/extinction" occurs the next day by viewing the blue square but not getting a shock, repeatedly, until they no longer display a reaction when it appears. This works, but unfortunately, the shock-conditioned fear recurs spontaneously a day or two later.
However, amazingly, if a blue square is shown w/o a shock, 10 minutes before the "replacement/extinction" routine begins, there is no subsequent, spontaneous, recurrence of the fear, even a year later. How can this 10 minute "reminder" before the replacement process starts cause such a dramatic difference?
As discussed earlier, it takes hours to consolidate memories into long-term storage. One of the classical papers on this subject, "Fear Memories Require Protein Synthesis In the Amygdala for Reconsolidation After Retrival" by Karim Nader, et al. in Nature in 2000 demonstrated that old memories could be changed when they are recalled.
As explained in earlier blogs, "Traumatic Memories Feel True, But Are Always Changing", and "The Influence of Misinformation", with each recalling, memories can be modified, and changed. This has allowed attorneys and law enforcement to manipulate the witness so that "false memories" resulted. i was in an fMRI study in which this phenomena was demonstrated. NJ has instituted new guidelines for questioning to deal with this.
This is why the simple planting of a "new memory" of a blue square which didn't shock and cause fear before "replacement/extinction" occurred was able to replace the emotionally-laden memory.
That is what we work with in meditation. If a strong, emotional memory recurs spontaneously, by focused inquiry or a psychological technique like "Big Mind", and it is not "feared"/pushed away, but is instead accepted with openness, there is no environmental reinforcement for the fear. If the trauma is met with a "Could I let go of this?, Would I let go of this?, When?" approach, it loosens its hold and the energy is fully or partially discharged before the long-term memory is reconsolidated.
There is a daily, first-thing-in-the-morning phenomena of the hippocampus/short term memory seeming to "ask" if its contents should be consolidated into long term memory by bringing them into consciousness. In my own morning practice, this is the period in which i normally chant Ramana's Upadesa Saram and the Bhagavad Gita as well as sitting in silence. This ensures that the short term memories will be "modified" with their energies either extinguished or dramatically changed if/when they are consolidated.
There is also a strong "body" component to traumatic memories; some PTSD sufferers say it is at least equal to the "mental" components. i strongly recommend that PTSD sufferers undertake a physical practice like yoga, or tai chi, which can reach many areas where trauma can lodge and manifest. There are many levels of yoga; find one appropriate for your situation. There are simple yoga routines on my website, www.happiness-beyond-thought.com. If you are unable to do yoga, then go for a walk, see a physical therapist, etc. Just as the trauma has been "embodied", so too do you need to work with the body to "disembody" it.
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| Donald Hebb |
A. An excellent Scientific American article in May gives some good insights on the neuroscience of how memories are formed and different approaches to deal with extremely painful ones, like Post Traumatic Stress Disorders (PTSDs), and to understand how to deal with painful memories that arise in meditation.
As shown in the graphic below (all graphics by Emily Cooper), memories are formed when the a stimulus activates the linkage from one neuron to a useful, functionally-related second neuron. As these neurons fire together, "Hebbian theory" operates, i.e. "neurons that fire together, wire together".
This theory, by Donald Hebb in 1949, relates to "plasticity" at the synapses between neurons. The efficiency of transmission across the synapse increases with "repeated and persistent" stimulation. The more times these neurons fire together, or in near "synchrony", the stronger this firing pattern becomes. Neuroscientists call this "long term potentiation" (LTP); we call it "memory".
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| Memory Formation - Short Term and Long Term |
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| ZIP Erasing Memories - All Memories |
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| Amygdala - Memory of Emotional Reactions |
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| Interrupting Storage of Painful Memories with A Drug So That the Memory is The Same but the Emotion is Gone |
This would seem to be a solution for PTSD, however...personal-injury lawyers, prosecutors, and "bioethicists" have gotten involved, as has the federal government. The ability of propranolol to alter memory-based evidence and modify behavioral response to past traumatic experiences has some "legal and ethical complications". A seminal paper "Therapeutic Forgetting: The Legal and Ethical Implications of Memory Dampening" by Adam Kolber was published in the Vanderbilt Law Review. There is now a federal law forbidding researchers from approaching patients directly; permission must be obtained from a clinical caregiver, like a busy EMT, which has slowed research.
There are also the side/after effects of propranolol, linked to significant "adverse drug reactions" due to high penetration of the "blood/brain" barrier to cause major sleep disturbances such as insomnia, vidid dreams and nightmares as well as extensive neuropathic pain.
 |
| Replacement of Painful Memories During Recall With New Associations So That "New and Improved" Memory Forms |
There is some excellent work in this area, which has much similarity to meditative practice approaches to pain and memory management. A recent, heavily cited paper is "Preventing the Return of Fear in Humans Using Reconsolidation Update Mechanisms" by Daniela Schiller, et al. @ NYU published in Nature in 2010.
A typical experiment is to condition subjects to expect a shock when they see a blue square on a monitor. "Replacement/extinction" occurs the next day by viewing the blue square but not getting a shock, repeatedly, until they no longer display a reaction when it appears. This works, but unfortunately, the shock-conditioned fear recurs spontaneously a day or two later.
However, amazingly, if a blue square is shown w/o a shock, 10 minutes before the "replacement/extinction" routine begins, there is no subsequent, spontaneous, recurrence of the fear, even a year later. How can this 10 minute "reminder" before the replacement process starts cause such a dramatic difference?
As discussed earlier, it takes hours to consolidate memories into long-term storage. One of the classical papers on this subject, "Fear Memories Require Protein Synthesis In the Amygdala for Reconsolidation After Retrival" by Karim Nader, et al. in Nature in 2000 demonstrated that old memories could be changed when they are recalled.
As explained in earlier blogs, "Traumatic Memories Feel True, But Are Always Changing", and "The Influence of Misinformation", with each recalling, memories can be modified, and changed. This has allowed attorneys and law enforcement to manipulate the witness so that "false memories" resulted. i was in an fMRI study in which this phenomena was demonstrated. NJ has instituted new guidelines for questioning to deal with this.
This is why the simple planting of a "new memory" of a blue square which didn't shock and cause fear before "replacement/extinction" occurred was able to replace the emotionally-laden memory.
That is what we work with in meditation. If a strong, emotional memory recurs spontaneously, by focused inquiry or a psychological technique like "Big Mind", and it is not "feared"/pushed away, but is instead accepted with openness, there is no environmental reinforcement for the fear. If the trauma is met with a "Could I let go of this?, Would I let go of this?, When?" approach, it loosens its hold and the energy is fully or partially discharged before the long-term memory is reconsolidated.
There is a daily, first-thing-in-the-morning phenomena of the hippocampus/short term memory seeming to "ask" if its contents should be consolidated into long term memory by bringing them into consciousness. In my own morning practice, this is the period in which i normally chant Ramana's Upadesa Saram and the Bhagavad Gita as well as sitting in silence. This ensures that the short term memories will be "modified" with their energies either extinguished or dramatically changed if/when they are consolidated.
There is also a strong "body" component to traumatic memories; some PTSD sufferers say it is at least equal to the "mental" components. i strongly recommend that PTSD sufferers undertake a physical practice like yoga, or tai chi, which can reach many areas where trauma can lodge and manifest. There are many levels of yoga; find one appropriate for your situation. There are simple yoga routines on my website, www.happiness-beyond-thought.com. If you are unable to do yoga, then go for a walk, see a physical therapist, etc. Just as the trauma has been "embodied", so too do you need to work with the body to "disembody" it.
nice pictures
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