Abreaction involves the expression of powerful emotions as painful memories are recalled. The patient is encouraged to express the previously blocked rage, fear, or distress. It is one of the oldest techniques in the treatment of psychological problems. It can be scary for both the patient and the therapist. Sometimes it is curative. The problem is that sometimes it also makes the problem worse. Its aim is to process the painful emotions that are bound to traumatic memories in such a way that the emotions are no longer painful. In this sense abreaction is similar to unburdening. Abreaction might even be called one way of unburdening. However, abreaction sometimes fails to do what it is supposed to do because the therapist and patient are not working directly with the part of self who carries the original memories of the traumatic events.
The unburdening that is the core of Parts Psychology accomplishes the unbinding of powerful emotions from painful memories through working with the part (subpersonality) that was created at the time of the trauma. The unburdening occurs internally as the patient directs her/his internal parts in a symbolic release of the pain connected to the memories. The patient does not engage in hysterical crying, raging, etc. in the therapy room. For example, the patient, guided by the therapist, might suggest that the internal part-self feel a rain wash the memories clean of negative emotions. The symbolic intervention might require repeating two or three times before the emotions for the memories are neutral.
Although I have borrowed the unburdening technique from Richard C Schwartz’s Internal Family Systems therapy, there are techniques in the work of Helen Watkins’ Ego State Therapy that also accomplish unburdening. For example, she describes “silent abreactions” in such a way as to make clear that her techniques, generally making use of hypnosis, also accomplish the neutralization of powerful emotions previously bound to memories.