But what if we could reduce or entirely erase constant, recurring maladaptive fears? You might be thinking that it sounds like science fiction. But some therapies such as EMDR (eye movement desensitization and reprocessing) and pharmacological treatments already disrupt and modulate traumatic experiences. The amnesia drug amnestic, for example, blocks new memories and causes reactivated memories to be forgotten by preventing re-consolidation. The process of re-consolidation occurs when a recalled memory is in an easily-altered state, and the memory must be "saved" all over again for it to be strengthened and stored long-term. But what if we could wipe out traumatic memories without drugs or prolonged and intensive psychotherapies?

A first of its kind study at the University of Bologna addressed this question by targeting the re-consolidation process in the prefrontal cortex to wipe out fears induced by negative memories. The new study, published in the journal Current Biology, describes a method of blocking re-consolidation to erase recurring trauma and alter how the prefrontal cortex functions so that an aversive event no longer induces fear. The research team, led by Sara Borgomaneri, used TMS (Transcranial Magnetic Stimulation) to create magnetic fields that alter neural activity in particular areas of the brain.

The 84 healthy study participants learned an unpleasant memory, created by paring an electric shock with certain images. After they learned the aversive memory, the next day, researchers presented participants with the same stimulus which had already been recorded as aversive. Ten minutes afterward, the scientists placed electromagnetic coils on the heads of participants and used TMS to interfere with the participants' prefrontal cortex activity.

Study participants who had their prefrontal cortex inhibited by TMS remembered the event but showed a significantly reduced negative physiological response to the unpleasant stimulus, as indicated by their skin conductance response. In contrast, control groups that underwent TMS without the recall of an aversive memory and without re-consolidation showed no decrease in physiological expression of fear.

According to the chief investigator, Borgomaneri, this is the first time these results have been obtained without the administration of drugs to patients, and the findings have implications for the fields of rehabilitation and clinical medicine. In the future, this procedure could alter the persistence of traumatic memories and pioneer the development of new therapies to assuage the recurrence of PTSD in patients.