I reported in my Free Will? book that we can laser in memories to fruit flies, so it was only a matter of time before such procedures were contextualised to humans. Scientific American reports [H/T Julian Haydon]:
Be it wounds of rape, war or loss: we all know people affected by traumatic events. As intangible as it is, psychological trauma is also very real: Events of extreme stress can force the cognitive restructuring of one’s worldview, sometimes to the extent that leads to major social disability, as in the PTSD. It’s now estimated that about 1 out of every 13 people in the US will have PTSD at some point in their lives. The high prevalence naturally brings about urgency in intervention yet unfortunately there hasn’t been much in the way of eradicating trauma, especially when it comes to distant memories. One of the most effective treatment options for PTSD is a cognitive restructuring practice called exposure therapy: A patient is continuously confronted with the original memories of trauma in order to open up a window of memory updating (termed memory reconsolidation). This renders the memory susceptible to positive modification. A major drawback remains that this is only applicable to the recent memories, while the intervention is most urgently needed for patients with remote memories of trauma, which are infamously stable and resistant to modification.
What I am interested in here is whether such procedures are better understood and explained the the context of a naturalistic/physicalist theory of consciousness and the brain, or whether some supernatural dualism better explains the ability to reformulate or affect memories. As the article continues:
The foundation of exposure-based techniques lies in invoking “plasticity” in brain, i.e ability to rearrange a given set of neural connections. During the rectification of a previously formed memory, the neurons reorganize to accommodate the new information. This plasticity is what enables us to select, archive and connect incoming data about the world in real time. Until now, both in mice and men alike, updating distant memories have proved problematic precisely because exposure therapy-induced plasticity has never been quite enough to reanimate the needed plasticity.
Epigenetics seems to play a pivotal role in this procedure, with its regulation of STOP and GO with genes in any particular cell. Epigenetics is the study of that which controls the on/off switches for genes themselves.
This is where the researchers were able to pick the lock on distant trauma: In addition with exposure therapy, they used an epigenetic modifier agent called CI-994, which inhibits the enzyme responsible for removing the GO signals. This was able to release the previously obscure veil over distant fear memories, leaving them susceptible to attenuation followed by positive adaptation. Similar studies have been done, in which investigators administered the epigenetic agent before the mice acquired the fear memory, which speeded its extinction weeks later. However, by nature, traumatic events are unpredictable and a treatment option that targets post-trauma symptoms, like of the one used in the current study, is more desirable.
I think that these studies definitely show at least supervenience and more likely some kind of naturalistic concept of consciousness. Consciousness is where science and philosophy so beautifully bisect.