Remembering to Forget: Memory Reconsolidation for Phobias

       Remembering to Forget: Memory Reconsolidation for Phobias

    As humans progress throughout their lives, they view their experiences as either positive or negative. The negative life experiences can quickly turn into avoidances and bad memories, which can eventually cause a person to develop phobias or fears of certain objects or situations. Phobias can also be caused by genetics or heightened symptoms of anxiety or PTSD. In a study by Keyes et al. called “Time intensive cognitive behavioral therapy for a specific phobia of vomiting”, intensive cognitive behavioral therapy along with slight exposure therapy is given to 8 participants with emetophobia. The participant data showed that the fear of vomiting was mostly persisting due to flashbacks of sounds, smells, and physical sensations associated with early aversive memories. (Keyes et al. 2019). In regards to the results being clinically significant, only about 50% of participants showed reliable improvement on the phobia intervention, and only two participants showed significant improvement. On the EmetQ measure, no participants achieved clinically significant change at any time during treatment or during the follow-up period. Overall, this study shows that more research needs to be done in regard to reversing the effects of phobias, and a better solution needs to be found.

    An experiment regarding memory consolidation is one tried and achieved path for helping with phobias and PTSD. Once retrieved, a memory can be disrupted before it is reconsolidated or returned to storage in the brain. In the article titled “Reactivating hippocampal-mediated memories during reconsolidation to disrupt fear” by Stephanie Grella, the link between memory retrieval and fear conditioning is shown. The dorsal dentate gyrus neurons are labeled in mice and first, they are naturally activated, and then post fear-conditioning these cells are artificially activated. Anxiety disorders, phobias, pathological fear, and PTSD are extremely prevalent, and using reconsolidation theory is one way to diminish fear and enhance the memory as they are being recalled. Reconsolidation theory states that memories become destabilized during recall as they enter a state of plasticity, where they can be modulated during the time it takes them to restabilize. This study used mice, which allowed for them to do longer exposures rather than for humans, as they did not want to be exposed to their phobia or fear for that long. The results showed that artificially inducing the positive affect of an experience prompted a suppression and a reduction of fear in the control mice. In humans, an effect known as the undoing hypothesis takes place where positive affect can protect against stress influencing health outcomes. Overall, if this technology is more generalized towards regular therapeutic services, then more people will be able to overcome and reduce the symptoms of their specific phobia, allowing them to lead better lives.

Keyes, Alexandra, et al. “Time Intensive Cognitive Behavioural Therapy for a Specific Phobia of Vomiting: A Single Case Experimental Design.” Journal of Behavior Therapy and Experimental Psychiatry, vol. 66, 2020, pp. 101523–101523, https://doi.org/10.1016/j.jbtep.2019.101523.

Grella, S.L., Fortin, A.H., Ruesch, E. et al. Reactivating hippocampal-mediated memories during reconsolidation to disrupt fear. Nat Commun 13, 4733 (2022). https://doi.org/10.1038/s41467-022-32246-8