The Theory of Structural Dissociation suggests that individuals with trauma and complex trauma-related disorders may be characterised by a division of their personality into different prototypical parts, each with its own psychobiological underpinnings (Dissociation). As one or more Apparently Normal Parts (ANPs), dedicated to daily functioning. Two or more Emotional Parts (EPs) are fixated in traumatic experience. As EPs, individuals predominantly engage action systems dedicated to defence/ past trauma (it happened, it is still happening). ANP and EP are insufficiently integrated but interact and share a number of dispositions of the personality (e.g., speaking). ANP is dedicated to functioning in daily life in the wake of trauma, and EP to responding to actual or perceived threat while being fixated in past traumatic experiences. Because ANP cannot properly integrate the traumatic materials contained by the EP, they are often highly phobic of and avoidant towards reminders of their trauma or further stress that could activate EP and so activate traumatic or symptomatic intrusions. These avoidant behaviors can involve amnesia, anesthesia (insensitivity towards or loss of certain sensory input), or limiting the ANP's range of emotions or numbing their emotional intensity. These avoidant behaviors can drain mental energy and allow for depression, anxiety, or chronic feelings of hopelessness, shame, guilt, or rage.
