Stress Disorders: Cortical Plasticity, Eye Saccades, and Multiple Personalities.

1993

 

Bruce E. Morton and *Sandra L. Paulsen

University of Hawaii School of Medicine

*Pacific Institute for Behavioral Medicine

Honolulu, Hawaii

 

Origin and Nature of Stress Disorders:

The Defense Response occurs as part of the switch from fearful flight (Ego) to cornered, fearless fight (Id) whereby the individual attempts to obtain freedom from restraint through the violence of defensive attack. The activation of the hypothalamic-pituitary-adrenal (HPA) axis is part of this response. Stress Disorders are pathological states resulting in inappropriate, repeated activation of the Defense Response. They appear to be produced from a maladaptive cortical plasticity that occurred whenever the Defense Response failed to protect the organism from trauma.

The cortical plasticity appears to result from neurochemical facilitation of pre-existing cortical synaptic connections to cause unconscious stimulus generalization. This causes the organism to respond defensively to any current stimuli that might be related to the past trauma. Stimulus generalization causes the present neutral stimuli to be subconsciously reconnected to the original trauma with all its poly-sensory memories, negative emotions, and altered states of consciousness. It also automatically reactivates the Defense Response tied to the original trauma.

Certain stress disorders are caused by maladaptive cortical plasticity from trauma in adulthood (Post-traumatic Stress Disorder, Chronic Pain and Fatigue Syndromes, Post-partum depression, etc.). Other stress disorders result from arrests of childhood critical periods of brain psychosocial development (OCD, certain neuroses, and psychoses). It appears that stress disorders afflict essentially everyone. Many ancient and newer methods temporarily relieve some stress disorder symptoms, often by elevating brain serotonin levels.

Stimulus-generalization is a form of cortical plasticity tied to memory, learning, conditioned response, and long-term potentiation. The critical period of feline visual development is the best-studied cortical plasticity system. It has revealed three specific conditions which must be met before cortical plasticity can occur: visual input, horizontal rapid eye movement saccades, and cortical norepinephrine (NE) release from locus coeruleus (LC) activation, either in eustress, (play) or in distress (trauma). Clearly, in PTSD and other stress disorders the original trauma included each of these three elements and would be expected to cause cortical plasticity-induced stimulus-generalization.

 

How EMDR Works to Eliminate Stress Disorders, Such as PTSD:

Eye Movement Desensitization and Reprogramming (EMDR) treatment of PTSD also inadvertently supplies all three of these requirements for cortical plasticity, i.e., it superimposes therapist-directed eye saccades upon standard flooding-desensitization techniques. This procedure has led to an in-session quantifiable reduction of upset and the measurable acceptance of a client-constructed statements accepting their traumas. Furthermore, the desensitization produced in session, appears to last indefinitely out of session at least for adult traumatization. The acceptance statement (a strategic element in PTSD treatment) appears to enable the ego to accept and "experience" the reptilian pre-memory- bound trauma, and thereby to abstract and integrate it into conscious awareness, including conscious memory access, so that current neutral stimuli remain neutral.

 

The Relationship of Traumatic Production of Stimulus‑Generalization and the Formation of Multiple Personalities: Under conditions repeated or pervasive trauma, the ego apparently can not adequately protect itself from confronting death by simple denial and repression. An additional ego defense is the creation of one or more fictional identities to insert between the true identity and the incidents of raw trauma, so as to keep isolated from it. As a result, entire memory segments associated with the false identity are laid down, and can be exited and reentered from specific stimulus-generalizing gateways. When an altered personality memory system is reentered, it would of necessity take on the surprising and disturbing familiarity of a dream from REM sleep. In theory, the trauma cannot be desensitized and reprogrammed by EMDR unless the person enters each false personality first and discharges it, then enters the true personality and completes that process.