AIP is a theoretical model that seeks to explain and predict the treatment effects seen with EMDR therapy. This theoretical model also describes the development of personality, psychological problems, and mental disorders. In EMDR therapy, the AIP model guides the principles and procedures of treatment. All humans have a physiologically-based information processing system. This is similar to other body systems, such as digestion or breathing (both of which extract and incorporate something the body needs for health and survival). The information processing system sorts through elements of our experiences and stores the important things in an accessible and useful form–called memories. Memories are linked in networks that contain similar or related thoughts, images, emotions, and sensations. From these associative memory networks, we create meanings, perceptions, attitudes, beliefs, and behaviors.
When a traumatic or very negative event occurs, information processing may be interrupted or incomplete. This prevents the forging of connections with healthy, more adaptive information that is held in other memory networks. The memory is then dysfunctionally stored with many elements still unprocessed. So, when the individual thinks about the trauma, or when the memory is triggered by similar situations, the person may feel like they are “reliving it”, i.e., experiencing strong emotions and physical sensations that push into present experiences. A prime example is the intrusive thoughts, emotional disturbance, and negative self-referencing beliefs of posttraumatic stress disorder (PTSD).
Trauma can include a single, major disturbing event (“Big-T Traumas”) and/or chronic, persistent disturbing events (“small-t traumas”) that occur over time. Traumatic experiences often undermine one’s sense of self-worth, safety, responsibility, and choice. Left alone, new experiences with accompanying distress or disturbance can form new, maladaptive memory networks. Thus, when similar experiences occur, whether internally or externally, they link into the unprocessed memory networks and the negative reactions, beliefs, and/or sensations arise. This expanding network reinforces and intensifies the previous experiences. By targeting these trauma memory networks with EMDR therapy, the brain reprocesses the previously dysfunctionally stored information and links it to other, more adaptive information. This process transforms all aspects of the memory; thus, non-adaptive perceptions, emotions, and sensations are released and discarded.