The Neurology of Memory Change: Can Traumatic Memories Be Erased?

Imagine the memories of trauma—the flashbacks, the fear, the pain—could be silenced or wiped away. This science fiction dream world is now the focus of psychology and neuroscience. Memory modification research is trying to erase or silence traumatic memories but not eliminate the very fabric of who we are. In this blog here, we examine the science of memory modification, how traumatic memories consolidate and reconsolidate, and the promise and limits of erasing trauma.

How Are Memories Formed and Retained?

Memories are not fixed traces; they are plastic and labile. At the time when a memory is first formed, it gets consolidated into long-term memory. Yet every time the memory is called up, temporarily it reverts to a state of labilitas in the process of reconsolidation. In this state, the memory is accessible to change prior to being stored again. Reconsolidation has dominated memory change research to date. Reconsolidation maintains that traumatic, entrenched memories can be rendered susceptible to modification if only we can catch them at that susceptible moment.

The Reconsolidation Process

New work by researchers such as Nader, Schafe, and LeDoux (2000) found that reactivated fear memories must go through novel amygdalar protein synthesis before reconsolidation. This discovery opened the door to therapy: if scientists can inhibit or modulate reconsolidation, they may be able to reduce the power of traumatic memories. One of the promising avenues is the employment of beta-blockers, such as propranolol. By giving propranolol within the reconsolidation window, there has been proof showing a reduction in the effective strength of fear memories. For instance, one of Brunet and colleagues' (2008) initial experiments found that post-traumatic stress disorder (PTSD) patients who received propranolol following recall of traumatic memories were less physiologically reactive upon later presentation with reminders of trauma.

Apart from Pharmacology: Behavioral Treatment

Besides the pharmacological treatments, behavioral treatment is increasingly becoming efficient tools in the modification of traumatic memories. Of these, extinction training and memory reactivation are the most promising techniques. Participants in one study by Schiller et al. (2010) initially received exposure to a conditioned fear stimulus and subsequently to extinction training on reconsolidation.

Other newer methods include Eye Movement Desensitization and Reprocessing (EMDR), where there are exposure elements with controlled eye movement. EMDR's mechanism of action

is presently unknown but has several rival hypotheses explaining how the bilateral stimulation being used will stop the reconsolidation cycle for traumatic memories and thereby reduce their affective charge.

Ethical Considerations and Challenges

Though the potential for erasing or altering traumatic memories is tempting, it poses very serious ethical questions. Memories, painful though they may be, are part of our identity and learning. Erasing trauma may have the potential to change a person's sense of self and life story. There is also the risk of unintended effects—if weakening some memories is therapeutic, can related, useful memories be impacted as well? Having clearly established ethical standards and full awareness of the whole range of long-term consequences will be crucial as the profession continues to evolve.

The second challenge is the fallibility of human memory. Trauma memories can be fractured, invented, or even distorted over time. It is a challenging task to build treatments that recover the "emotional tag" of such memories again and again without disrupting other memory processes, and it requires finesse sensitivity of neural circuits as well as interindividual differences.

Future Directions in Memory Modification Research

Future memory modification research has great potential. Advances in neuroimaging and molecular biology are continuously shedding more light on the molecular mechanisms of reconsolidation of memory. As more discoveries are made, researchers are making increasingly selective interventions. For example, there will someday be novel ways of gene therapy for specifically modifying reconsolidation molecular mechanisms with adequately targeted treatments for trauma.

In addition, interdisciplinary teamwork is required. Psychologists and neuroscientists need to have collaboration in order to design useful interventions that are ethically based. Clinical trials are moving toward the integration of pharmacological and behavioral treatments in order to produce maximum therapeutic gain with minimum risk.

Conclusion

Memory modification is a promising field in the treatment of trauma. By triggering the brain's internal process of reconsolidation, scientists have begun to open the doors to reducing the burden of traumatic memory. While the potential for the "erasure" of trauma is replete with difficulties and ethical risks, science in this case also holds out the promise of freeing up improved treatment of PTSD and associated disorders. With continued science, there is the potential for greater insight into memory change that not only relieves suffering but informs the treatment of mental illness.