In the movie Eternal Sunshine of the Spotless Mind, the average person in the not-too-distant future has the option to erase unwanted memories with ease. The film takes a bizarre trip through Impenetrable Symbolism Lane after the initial setup, but the idea was ultimately painted as residing in an ethical gray area. In that story, a man was forgotten by an ex-girlfriend, but it was implied that the same technology was being used to treat PTSD and help people forget highly secretive information as well. A recent pilot study by University of Montreal researchers at the Centre for Studies on Human Stress has suggested that, while such specific deletion of memories is a pipe dream at best, the dream of removing painful memories with an accessible treatment may not be so far from our grasp.
The drug metyrapone, a drug that inhibits the production of the so-called "stress hormone" cortisol and is used in the treatment of hypercortisolism, was given to 22 men, with half receiving double the dose given to the other and another 11 men receiving a placebo. The men were administered the drug four days after being shown "a slide show having neutral and emotional segments," according to the paper published in the Journal of Clinical Endocrinology & Metabolism, and asked to recall parts of the sequence. The study found a statistically significant decrease in the ability of those with the highest dose of the drug to recall those portions of the slide show which were most "emotional," while the more "neutral" parts were easily recalled by all three groups. This suggests a possible use for the drug in the treatment of PTSD.
Yes, sample size was tiny, and I would argue that the experimental design is rife with subjectivity, but the idea is founded on good science. It's fairly well established that cortisol has a significant effect on how our brains process and store memories. Typically, higher levels of cortisol impair accurate memory recall while also causing powerful emotional associations with memories being stored. The idea that we can specifically target and inhibit the recall of these emotional aspects of bad memories, without destroying memories of an event outright, is an intriguing and enticing one. While many may raise concerns over tampering with our memories in this way, the availability of such an option to those struggling with truly agonizing emotional memories would be almost entirely positive, and the effects may well be more permanent than with drugs many use to cope with negative emotions (like alcohol). The truly interesting issue to me is that it is this easy to mess with memories at all.
It's already well established that the ability to process and store memories can be removed by removing certain parts of the brain. It's also well established that certain drugs can inhibit memory recall. This preliminary study hints at the possibility of removing certain associations in the brain with pharmaceuticals. That memories are as beholden to peculiarities of biochemistry as any other biological process is not surprising, but it suggests that the scenario portrayed in Eternal Sunshine isn't very far fetched, or far-off. It's difficult to argue that such a world would be better or worse than the one we have now, but it would be radically different. Imagine being able to purchase this drug over the counter (it has relatively minor side effects) when you lose a loved one, and dramatically cutting down on grieving time. Such a world may well be a more efficient, more callous world, but perhaps callousness is worth having a "cure" for PTSD.
Science Daily article summarizing the paper: