When the Past is Always Present Part 4

5.

ENCODING A TRAUMATIC MEMORY.

There are four conditions that need to be met for an event to be encoded as a traumatic memory. First, one needs an emotion-producing event. Second, the event must have meaning for the individual. Third, the brain's neurochemical landscape at the time of the event must be suitable, and fourth, the event must be perceived as inescapable. If these are present, then, through the intermediacy of the amygdala, an enduring imprint of the moment and its a.s.sociated components is synaptically encoded. The event has been traumatized.

Requirements for Traumatization.

Why are some traumatized by an event while others are unscathed? We speculate that there are four conditions that need to be met for a traumatic encoding moment to occur (Figure 5.1).

The Event.

Life has traumatic moments. In order for an event to be traumatizing, it must produce an intense emotional response. We can be part of it, we can witness it, or we can be told of it and be traumatized. We can be trapped in a burning building, we can see a building burning and hear the screams of people trapped, or we can hear the stories of burned survivors and be traumatized. A second- or thirdhand account of the event can lead to traumatization because our mind imagines it. This is the origin of vicarious traumatization seen in social workers, therapists, lawyers, police officers, and others dealing with trauma on a regular basis. While a first-person experience will have a greater affect than a third-person account, vicarious traumatization has been studied and workers in the field of trauma therapy must be aware of these dangers.1 Figure 5.1 Requirements for traumatization. (Courtesy of Ronald Ruden and Steve Lampasona.) While on an airplane, Samuel experienced severe anxiety when the person in front of him reclined, moving the back of the chair close to his face. He was able to trace this back to a moment when his mother told him that she did not want to be buried underground. He had imagined his mother in a coffin, with the lid close to her face, and this traumatized him. This vicarious traumatization overlapped with the feeling of being trapped on the plane and initiated an anxiety response.

The event does not have to be life threatening or even put us at risk. Riding down an escalator hardly qualifies as a dangerous activity, yet this event strikes fear in those with a fear of heights. Swimming in water over your head (drowning/suffocation) can be fear producing. Watching an animal killed can frighten you (vicarious). Seeing your child sick can be frightening (loss/abandonment). Even made-up stories with horrible endings can produce fear (imaginary). The list of things that can produce strong emotions is endless.

In the final a.n.a.lysis, the emotional event must cause norepinephrine and cortisol to rise to high levels to meet this requirement for traumatization. Norepinephrine prepares our mind for quick action and increases our ability to process, a.s.sociate, and store information. Norepinephrine also activates an amygdala-prefrontal pathway, preventing the prefrontal cortex from inhibiting the amygdala. Cortisol enhances norepinephrine's actions. Dopamine is also elevated at this time, causing the content and context of the event to become more salient.

Meaning.

The second requirement for traumatization is that the event has meaning to the individual. Meaning arises as a result of our innate need for attachment and our previous experiences. Meaning is understood early on when, as an infant, we see our mother walk into the room and we smell her skin, knowing that we will be held and caressed. We will also have our wet diaper changed, and the uncomfortable sensation of hunger will evaporate when we get to drink the milk she provides. Her entrance is all about pleasure and the removal of pain. The meaning of this entrance obviously changes over time, but it is arguably the most powerful attachment we will ever experience.

We are, of course, highly attached to living, and the potential loss of our life is certainly meaningful. Indeed, the possibility of being killed produces an intense emotional response. A traumatizing event, however, does not always involve a life-or-death moment. Any loss of attachment can cause great emotional turmoil. The loss of stature in your community, the loss of youth, the loss of self-esteem, the loss of ability to provide for your family, the loss of a limb, even the loss of a tooth are all meaningful events. Whether this loss leads to a traumatization depends on the other requirements being met.

Meaning is not just about self. Loss of any attachment, such as your child, spouse, parent, friend, caregiver, lover, pet, or country, is filled with meaning. Attachment, the not being alone, drives us to form friendships, exhibit patriotism, join country clubs and houses of worship, and live in certain communities. The armed forces develop this meaning to produce cohesive units, ready to sacrifice for those to whom you have become attached. It is this fear of loss of attachment that gives power to meaning.

We can also have attachments to nonliving things. Our home is a place of great meaning. It is full of memories to which we are attached. Losing our home because of natural events (flood, fire, and all that nature can produce) or financial events (loss of job, becoming disabled) or man-made events (war, loss of a sense of safety) can be traumatizing. For example, loss of a sense of security in our home, if it is burglarized, can be traumatizing.

Buddha recognized attachments as the cause of craving and suffering. He strove to rid himself of these attachments by becoming one with the universe.2 Most of us are unable to accomplish this and our attachments cause suffering. It is often only through the pain we experience when an attachment is lost-through death, separation, or a simple breakup-that we begin to appreciate its power. It is from this feeling we learn to protect that to which we are attached.

Aside from the emotional needs, attachment also has a physical component: touch. There is a powerful biological need for mammals to be held, caressed, comforted, and cuddled. Touch is how Michelangelo's G.o.d gives life to Adam in the Sistine Chapel. Touch has an extrasensory component that provides meaning. It is what drives animals to herd. As Francis Galton,3 the 19th century naturalist, observed: The ox ... cannot endure even a momentary severance from its herd. If he be separated from it by stratagem or force, he exhibits every sign of mental agony; he strives with all his might to get back again and when he succeeds, he plunges into its middle, to bathe his whole body with the comfort of close companionship.

Attachments, physical, personal, and public, are the fundamental brick and mortar of meaning. Without attachment there is no meaning.

Meaning can also be based in previous experience. Events that in and of themselves may not appear to be threatening to observers can be a reminder of terrifying events from another's past. Thus, Susan, who had been kidnapped and molested when she was a youngster, screamed and cried hysterically when a stranger unexpectedly patted her on the behind. It was this earlier event that gave meaning to a seemingly minor incident. While events that evoke intense feelings in most individuals are easy to recognize, one's past, flush with meaning for the individual, may be all that is needed to produce a traumatization. It is therefore not for us to judge what const.i.tutes a meaningful event. Thus, in searching for the traumatizing event, do not dismiss clues that may seem trivial to you.

Landscape Needed for Traumatization.

What is a landscape? One can define the landscape of the brain as its neurochemical state at any given time. For the purposes of this model we have chosen five neurochemicals believed to be necessary for traumatization (there are, of course, other molecules, such as acetyl choline, involved). These substances are glutamate, dopamine, serotonin, norepinephrine, and cortisol, and they affect how information is processed in the brain. As baseline (tonic release), these chemicals act as neuromodulators affecting mood, information processing, and altering our vulnerability to traumatization.

During acute stress, the levels of these regulatory neurochemicals are dramatically increased (phasic release). These higher levels cause information to be processed differently and are necessary for traumatization. It is here they act as neurotransmitters, telling the body to get ready. These new levels make us pay attention, sharpen our senses, motivate us to action, and prepare the brain to store the incoming sensory information. Thus, rising dopamine will occur when we are seeking the presence of a potential predator, as it increases our ability to recognize predator-related cues. When fighting or fleeing, high norepinephrine and epinephrine prepare our mind and body. Serotonin also rises slightly to prevent the system from becoming overwhelmed. Glutamate is involved with all of these processes.

These neurochemicals are also altered during chronic inescapable stress. Here, tonic levels of serotonin appear to be lower, and depending on the circ.u.mstances, cortisol and norepinephrine can be either elevated or decreased. Chronic stress appears to alter the landscape of the brain in such a way as to make it more vulnerable to traumatization. This is why traumatization (a form of inescapable stress) begets further traumatization.

Neuromodulators and Neurotransmitters.

A neuromodulator is a substance that affects information processing and is secreted at a homeostatic baseline level. The baseline levels of neuromodulators reflect the sum of our inherent psychological makeup, old traumas, internal physiological states, recent experiences, and hormone levels. Neurotransmitter release is predicated on the perception of a threatening or novel stimulus. The brain is made of various interacting subsystems, each with its own types of neurochemical receptors. These receptors can activate protein synthesis or alter the permeability of the neuron to which it is attached. The release of these neurochemicals can produce short-term action or long-time change. The neurochemicals involved with traumatization act both as modulators and transmitters.

Norepinephrine-As a neuromodulator it regulates mood and anxiety. It provides for greater accuracy in retrieval of information. As a neurotransmitter it activates our physiology needed for fleeing or fighting, increases our vigilance, and improves our ability to store and retrieve information and produce a.n.a.lgesia. Norepinephrine is essential to inhibit the outflow from the prefrontal cortex to the amygdala, thereby shifting control over behavior to the amygdala.

Dopamine-As a neuromodulator it sets the stage for alertness and smooth movement, helping us seek out what is important and go there or run from it. As a neurotransmitter it is used to increase salience, vigilance, and motivate action.

Serotonin-As a neuromodulator, elevated levels decrease one's ability to seek related information and provide resilience to traumatization. Serotonin prevents us from becoming overwhelmed by too much sensory input. Conversely, lower levels increase our ability to form a.s.sociative connections and increase susceptibility to traumatization. Behaviorally, lower tonic levels are a.s.sociated with aggressive and compulsive activity. As a neurotransmitter, elevated levels of serotonin, along with other neurochemicals, provide for a feeling of satiety and safety.

Cortisol-As a neuromodulator it regulates many systems (e.g., immune) in the body and has a known diurnal rhythm. Released during stress, it appears necessary for encoding and healing.

Glutamate-An excitatory amino acid (EAA) neurotransmitter that also increases the effect of other neurochemicals. It is critical for storage and retrieval and for linking components of an event. Without glutamate and its receptors, no information will be stored. Glutamate and its receptors light the pathway by which information travels.

GABA-An inhibitory amino acid (IAA) neurotransmitter that acts by promoting the effect of other neurochemicals. Through its action storage and retrieval of information are inhibited. It is yin to glutamate's yang. If glutamate opens a path, GABA closes it.

A Vulnerable Landscape.

As mentioned above, the levels of these neurochemicals are modulated by our inherent sensitivity to stressors, our inherent psychological makeup (temperament, compulsive tendencies, etc.), environmental influences (living conditions, p.u.b.erty), recent experiences, and long-term memories that include earlier traumatic memories.

What are some of the circ.u.mstances that alter these levels and increase our vulnerability to traumatization? Recent research has shown that adverse prenatal and early postnatal experiences can influence long-term development (see www.developingchild.net). p.u.b.erty is one of the great landscapers of the brain. This landscaping is due largely to the effects of testosterone and estrogen on the brain. These substances act as physiological stressors of enormous power, as shown by the intense effect these substances have on rational thought and emotional behavior.

The role of previous experiences on susceptibility to traumatization is critical. As mentioned earlier, the term used in psychiatry is kindling, which means previous stressful events can alter sensitivity to future events. On a molecular level, kindling produces an increase in excitatory glutamate transmission and a decrease in inhibitory GABA transmission in the amygdala. Prior stressful events change perception for a current event. For example, preschoolers who witnessed the September 11 attack on the World Trade Center were at high risk for developing lingering emotional and behavioral problems only if they had had a previous frightening experience, like seeing a parent fall ill. It is unclear from this study whether these earlier frightening experiences resulted in traumatization. Nonetheless, it was found that 40% of those who had such sequential traumas suffered from depression, emotional outbursts, and poor sleep three years later. By contrast, children who saw the attack or its victims but had no such earlier trauma showed few, if any, psychological scars. What is remarkable is that previous traumatic events could be anything from a dog bite to a serious accident.4 This simple but powerful ill.u.s.tration broadens our understanding about what can sensitize an individual to traumatization. How does anyone get through life without one of these seemingly minor experiences that can kindle? And if so, why doesn't everyone become traumatized?

What clinical features guide us to know who is more susceptible? Vulnerability is increased by overly empathetic abilities, low self-esteem, and difficulty in regulating the level of emotional response. Personality traits such as obsessive-compulsive disorders, anxiety, introversion, and substance abuse also increase risk. The stressors caused by poverty and low education levels independently increase risk for traumatization.

A Resilient Landscape.

Resilience to traumatization, on the other hand, is a.s.sociated with good intellectual functioning, the ability to regulate emotional responsiveness, optimism, appropriate attachment behaviors, an active problem-solving approach to circ.u.mstances, and a sense of being self-contained, that is, experiencing moderate needs and desires. One can also landscape the brain to aid in resilience. Techniques such as yoga, meditation, and exercise can improve our chances of avoiding traumatization (see Appendix B).

Inescapability.

Escape requires movement and fear can produce it. Running, jumping, climbing, flying, burrowing, swimming, and fighting all involve motion. If we cannot move or hide we are trapped. A perceived inescapable threatening situation has the potential to traumatize. The perception need not last long, nor is it necessary for this perception to reach conscious awareness. Inescapability can occur during a car accident, when you are falling down, when you cross a bridge, when you are in a combat situation, or when you are told you have cancer. There are many life events for which there is no place to run and hide. It is that moment when the thinking and planning part of the brain, the prefrontal cortex, is taken offline and we are subject to control by amygdala outflow. When all four requirements are met, the event is encoded as a traumatization.

I am a 48-year-old widow who lost my 41-year-old husband of 22 years in a very tragic accident on January 5, 2006. We had a wonderful marriage and family life; we had one beautiful child and were very much in love. Larry* was my soul mate. He was an absolutely wonderful man; everyone I knew loved him. He was an amazing dad to our child, and his loss has just about ruined her as well. What happened? It was the day after Christmas 2005, he was on vacation until January, and he woke up one morning and said, "Who wants to go on a random road trip to Florida?" My daughter and I replied, "We do. We do." And within hours our minivan was packed, headed to Florida. We spent an amazing 10 days there; I must say the last 10 days of his life were amazing! On our drive back to Ma.s.sachusetts, I reached over to him and said, "Kiss me, I love you so much and hope I die before you, because I don't think I could ever live without you." And he replied, "Don't worry, Hon, I am going to die before you, I am going to die young."

The very next day he went to work, called me around 10:30 a.m. just to tell me that he missed me, what he wanted for dinner, and said he would call before leaving so I could boil the water for the ravioli I was making. He called me every day when he left work. So he called me, said there was a problem and he would be a little late (he was the building engineer for a commercial real estate company in Boston). I then received a phone call two hours later saying he would be later, as something else had come up. (That was the last contact he had with anyone according to the cell phone record.) Immediately after the phone call, I had a very strange feeling inside; I then proceeded to call him over and over again, no answer. A few times I had a fleeting thought that something was wrong, but didn't act on it-I just a.s.sumed he was very busy. Three hours later my phone rang and all the man said was, "Mrs. Stanger, this is the president of Hopewell Industries [that's where he worked]." And I screamed, "Larry is dead!" I just knew it. He said, "No, but there has been a terrible accident and you need to get to Cambridge Hospital right away." There are no words to express the sheer terror that came into my body all of a sudden. I forgot how to get to the highway, just a few minutes from my house; what should have taken 20 minutes took an hour and a half. My daughter's boyfriend drove us. When we did get there, a policeman escorted Lilly (our daughter) and me into a small room. The doctor just turned his head (I will never forget that image) and shook it. He told me he was gone. I screamed "No, no, no!" for a few minutes, and suddenly felt as though it was all a dream.

Larry had been up on the roof, 4 stories high; he was looking at a vent shaft and slipped off the roof. On his fall down he took out a huge window air conditioner and probably bled to death because, although people heard a loud crash, n.o.body went out until 45 minutes later.

The next few months were surreal. Many times I felt as though it was all a bad dream and that I would eventually wake up and tell him what happened. But, of course, that never happened. What made it extremely difficult was how he died-that made the grief much more complicated. Fortunately, I met a woman at the church who gave me a beautiful thought; she said that as Larry was falling, the angels were caressing him and he did not feel a thing. That thought has brought me much comfort.

Prior to this horrific tragedy, I never had any emotional issues. I always felt that I had a very strong, balanced mind and a wonderful outlook on life; never believed in medication of any sort-both Larry and I always felt society was overmedicated. We were very spiritual and basically very content. We tended to view the world from the same set of eyes. When it first happened, I did call my primary care doctor for something to help me sleep, because I was racing so much. I could go three to four days without sleep; it was horrible. I believe I grieved rather well, if there is such a thing. I cried, sobbed, cried, and sobbed for months and months. About the third week after the accident, I had a wonderful dream where he called me and said "Hi" in a very happy tone, the way he would say hi when he called our daughter, and he said, "I'm OK." And I screamed, "Larry, are you in heaven?"

And he chuckled in this very happy tone and said, "Yes, I am." When I woke up, it was the strangest thing, I had this sort of buzzing vibration in my left ear, and I felt so wonderful (a feeling that lasted a few weeks), because it was so important for me to know he was okay. The months went on. My daughter and I did not grieve together; she went to live with her new boyfriend and I became suicidal and depressed. As time went on I began trying everything to move past the darkness. I ran several miles a day, went to the gym, and started practicing martial arts. I constantly felt I was racing and running, and I guess in a sense I was: I was running from my pain. All in all, I would say I did very well with my grief, as I feel my strong spiritual foundation helped me. Although, in the course of the grief, I did feel anger at G.o.d, but thankfully that has pa.s.sed. I now realize we each come to this life experience with a purpose, and a job, and when it is done, we return to the spirit world.

About 10 months after his death, a distant relative pa.s.sed away at 39 years old; she had lupus. She had been with her husband about the same amount of time I had been with mine, and they had a similar soul mate relationship. I initially reached out to him because I didn't want him to go to the h.e.l.lish dark places I did, as I felt I did a good job in preventing that for myself. They had a little son who at the time was almost 6, and he was very sickly. He was born a twin and a preemie and spent his first year of life in the hospital. When I met the little boy he was on a feeding tube and in diapers and only spoke in one- or two-word utterances. After four months of my being in his life, I got him off the feeding tube and potty trained. I took him to specialists and found out he was severely autistic, and now, three years later, he has been diagnosed with epilepsy, mental r.e.t.a.r.dation, ADHD, a periventricular brain injury, and a white matter brain disease of unknown etiology. This little boy was like my medicine-all the love I had for Larry I was able to pour into him and into my helping him. So, they came to live with us and life became very challenging (this was about a year after Larry's death). I believe this is when the PTSD started to kick in.

I couldn't concentrate, became very agitated at things that would never bother me. I couldn't tolerate sitting in traffic, waiting in lines, stress from Junior (the little boy). I had broken sleep, couldn't fall asleep, or if I did, I would awaken every few hours feeling very racy (this still happens). Whenever Lilly would go out (which is not often), I would panic if I heard fire engines or ambulances. I envisioned her in an accident and became terrified, like crazy, and would feel all the physical symptoms I did that night in the hospital when Larry died. I get very thirsty, I have to go to the bathroom, and just shake and become filled with immense fear. When she goes out I text her and call her several times to be sure she is okay, and this is so unhealthy for her as well as myself, as I feel it is destroying my insides. I was always a peaceful, patient person, and now I have no peace and am extremely impatient, especially while driving. I get so infuriated at the most trivial things. I cannot concentrate (I almost feel as though I have ADD now). I feel like one huge ball of anger, and this is not me-not who I ever was. I just want to feel at peace again. It is ruining my relationships, my life, my daughter's, and Arnold and his son, who live with me. I really need help. I just want to get better.

As far as treatment and meds go, they did give me the lowest dose of lorazepam (an antianxiety medication) when the accident happened to help me with sleep. I take them when I cannot sleep, or if I am in a panic when Lilly goes out and I cannot contact her. I also tried grief therapists in the beginning, but fired them all, as I realized there was nothing any of them could do for me. I felt it was a spiritual thing that I had to go through myself, and I feel as far as the grief went, I did grieve in a very healthy way. Then I found the Trauma Center just outside of Boston. I was seeing a therapist there and she tested me and said I had depression and PTSD. I was, and still am, extremely hypervigilant-no intrusions thankfully; they subsided early on. Since I was against meds, my therapist suggested I try St.-John's-wort, which did help with giving me energy to do things, clean my house, and cook again, but it did nothing for the panic and the PTSD. She also gave me EMDR, which seemed like it was helping. We never got to the point of going through the entire treatment. It started to get very expensive, and then I got angry because she said she couldn't treat my daughter, as it would be a conflict of interest. So the old ugly PTSD reared itself and I fired her. I then asked my primary care doctor for meds, as it's gotten so bad. I just want this PTSD out of my life. I tried sertraline (an antidepressant, antianxiety medication) for about six days, and after taking it I would start to get anxious and had to take lorazepam to calm down. I did not like the feeling, so I stopped it. I then tried citralopram (another antidepressant/antianxiety medication) and it did the same thing, so I am on nothing now.

All I want is to heal, to be calm again, and to be able to clean my house, cook, take care of my gardens, and help my daughter. I do have plans to write a handbook on sudden traumatic death, as there is really nothing out there (at least not written by someone who experienced it and survived it). But there is no way I can do this, as my ability to concentrate is gone. I am definitely a warrior, but this is one battle I cannot seem to fight on my own.

Her experience certainly produced an intense emotional response and it is likely this resulted in traumatization. However, it was the subsequent stress arising from the challenges of caring for an autistic child that altered her landscape allowing for the production of symptoms and a diagnosis of PTSD. When you finish Chapter 8, come back to this story and try to see what moments you would choose to haven. Chapter 10, on trauma cures, recounts what happened to her after havening.

Traumatization.

A memory is traumatically encoded when the brain is vulnerable and escape from an emotion-generating event is not perceived to be possible. While some of the processes leading to this type of encoding are known, much remains a mystery. The only good thing about this mystery is that we know where to look for answers-in the brain. Unfortunately, the brain is still a bigger mystery, and here we heap a mystery upon a mystery. What sounds like a fruitless search is not. We are now able to map the brain using various techniques. We can use chemical probes, scanning techniques, and lesional (destroying part of the brain in laboratory animals) and clinical methods to dissect the neural happenings. It is from the knowledge harvested from research that we begin to understand this process.5 To be able to erase a traumatically encoded memory, we must first have a common language with which to speak. We define traumatization at the neural level as the process that permanently encodes and synaptically consolidates linkages between the emotional, cognitive, autonomic, and somatosensory components present during the traumatizing event. Any one of the components recalled either consciously or subconsciously, activates the amygdala and causes the release of stress neurochemicals. For each reactivation, we experience some or all of the components as if they were happening for the first time.

It is important to note that these components are stored in several places in the brain. It is the amygdala that modulates the binding of the components present during the traumatizing event. Further explanations are required. When we use the word emotional, we are referring to the affective response to an event. Emotion is a felt sense. By cognitive we mean both the content and the context of the event. In recalling a traumatic moment, the context is often overshadowed by the fear stimulus and is not readily retrievable. By autonomic we mean the automatic brain functions that help us swallow, regulate body temperature, speak fluently, and control waste disposal. By somatosensory we mean sensed throughout our bodies, such as pain, numbness, tingling, skin temperature, hypersensitivity to touch, and other sensations.

Components of a Traumatic Memory.

Emotional.

Autonomic.

Cognitive-Both conscious and subconscious components.

Somatosensory.

By subconscious we mean mental content, generated by internal or external cues, not consciously registered, but nonetheless able to stimulate somatic symptoms and emotional arousal. Conscious means mental content we hold in thought or attention and we are aware of its presence and meaning.

We specifically avoid here the ambiguity of what makes an event traumatic. Since not everyone who experiences the same event is traumatized, an operational definition that defines the process and consequences of encoding is preferred.

The cognitive component of the memory of the traumatized event accessible to conscious retrieval is simply called a traumatic memory. These memories are bound into a coherent narrative whole. The cognitive and emotional response are linked. Cognitively dissociated traumatic memories are stored and/or retrieved differently. They are brought to conscious awareness without effort or control on our part through flashbacks, nightmares, intrusive thoughts, and bodily sensations.

Traumatic memory-Thoughts and emotions that are a.s.sociated with conscious activation or inadvertent reminders that lead to recalling of the event and its emotional content. Stress-related neurochemicals are released.

Dissociated traumatic memories-Thoughts, feelings, and sensations that are experienced when activated by stimuli that arise from abnormal retrieval and cause the release of stress neurochemicals.

Dissociated Traumatic Memories.

Dissociation is a complex and poorly understood phenomenon.6,7 Parts of a traumatic event can be dissociated and remain beyond conscious recall. This type of memory is puzzling because when it enters consciousness, the individual cannot relate it to his or her current state. Emotions may appear unbidden. Pain may be present but the cause is a mystery. All sorts of autonomic dysfunction may occur.

Beth had severe localized chest pain and tenderness. There was no evidence of any recent trauma. Her life was about to change because her husband had been convicted of a crime and was about to be jailed. She was terrified that she could not provide for her children. The last time she felt this fear was when she had a lung biopsy at the site of the current pain. This also produced terror, when she was afraid she might have cancer and would die and not be able to provide for her children.

Here a similar emotional feeling, the fear of not being able to care for her children, brought out a somatic component.

To make matters even more complicated, dissociation may not be just the result of an extremely horrific moment where very high cortisol levels disrupt hippocampal functioning. Dissociation may also be developmental. If traumatizing events occurred in early childhood, generally before the age of 4, the cognitive portion of the event cannot be stored because the hippocampus, the narrative memory processing center, has not yet developed. The emotional components, however, remain biologically active. Thus, early childhood traumatization, such as abandonment or physical or emotional abuse, may cause permanent alteration of the landscape by continual activation of stress neurochemicals.