Sunday, April 27, 2008

What We Need to Know About the Brain

In order to offer the most complete healing possible to children with histories of trauma and attachment disruptions, we have to understand something about the brain, how it develops and how trauma effects that development.

Human beings develop through relationships. We have mirror cells in our brains that fire when OTHERS express emotions, creating similar emotions in us. This happens countless times between a mother and a baby. It is the basis of empathy. Human society is built on this interactivity, because relationships necessary for survival.

Infants are born dependent. Luckily, parenting is pleasureful. The infant associates touch with pleasure. She gets her needs met, gets relief from distress, which calms anxiety. Her brain develops a sensory pattern of human interaction associated with pleasure. A template is established. Thus our early experiences contribute the template: our definition of "normal".

Attachment and the Brain
Early attachment relationships sculpt the brain’s survival circuits and make them more or less able to regulate emotion when faced with stress. Secure attachment facilitates thoughtful processing, counters the survival-in-the-moment reactions to stress. We have evidence that loving relationships can help change the brain, regulate the amygdala and the survival-in-moment circuits. The nature of the child’s early attachment is etched in lower levels of the brain. Children respond from that place without awareness.
Although attachment is necessary for safety, humans are also our most dangerous predators. Therefore we are very sensitive to the moods, expressions, and gestures of others. Our stress responses very closely tied to systems that read and respond to social cues.

Principles of Neurodevelopment

The brain grows most rapidly from birth to age four. At 4, its 90 per cent of adult size.
Implication: The greatest opportunity to grow and influence the brain is with the developing child. This period also presents the greatest vulnerability to the destructive impact of threat, neglect, and trauma.

The brain develops from brainstem up to the more complex parts of brain. The primitive parts of brain are the most difficult to change (least plastic).
Implication: Change is possible, but is slow with early trauma. To change, we need repetition, repetition, repetition.

The brain neurons grow in a "use dependent" fashion. The brain sets down a "template" for how life is supposed to be and go. The brain and reacts particularly to any thing out side that template, anything new. To change a muscle through exercise, we must have moderate, repeated, patterned extra stress. Then the brain decides, oh, we are going to be doing this now, better develop some new muscle cells. It is the same with brain cells. The stress is a signal to the cortex- something new is going on here. Moderate stress is good for the brain and the body, it develops our ability to handle stress. However, imagine going to the gym for the first time and trying to lift 200 pounds. It would not build muscle or teach the body anything. You would hurt yourself. This is similar to the stress children receive from trauma.
Implication: Interventions need to be consistent, predictable, patterned, and FREQUENT. Kids with attachment problems need many, many positive nurturing interactions. The number of repetitions needed for change is so high that most adults become discouraged. We have unrealistic expectations about pace of change.

Trauma-related symptoms originate in brainstem and lower parts of the brain.
Implication: When brainstem-driven, the brain processes and functions differently (Perry, 2006). The child’s responses are mostly unconscious, old brain fear responses (not intentional). Cognitive, rational, highly verbal interventions generally don’t work. Conventional therapies will fail if the brainstem poorly regulated. Therapeutic interventions must influence the brainstem and lower parts of the brain.

The brain develops in sequential fashion from brainstem up to cortex. If a sensitive period in brain development is missed, may be hard or impossible to re-create later. For example, if a kitten’s eye is kept closed during a certain period of sight development, may never develop sight even if opened later. So traumas at different ages have differing effects depending on what the brain was working on at the time.
Implications: CBT, insight-oriented will fail if the brainstem is poorly regulated. Once the brainstem is regulated, the child can benefit from more traditional therapies. Just like healthy development, healing from trauma starts from the bottom up. The sequence of interventions matters. We must match interventions to child’s level of neurodevelopment. Examples of interventions to regulate brainstem are music and movement activities like dancing and drumming; EMDR; patterned massage; repetitive, consistent positive interpersonal interactions.

In order to develop, we need repetitive, patterned interactions. Rhythm is very important to human functioning. We need reliable internal cycles to sleep and wake, when to eat, heart rate, etc. The brain changes through repetitive, patterned activity. Rocking is a human comfort response, as exemplified by a person in crisis rocking back and forth or a chair.
Implications: Healing is facilitated by repetitive, rhythmic activities such as drumming, dance and music. Regular structured predictable schedules are also important.

Emotion is the central organizing mechanism of the brain. Humans are hard-wired to pay attention to sex and danger. Advertisers know this!

Although many things are learned through repetition, it is critical to our survival to learn quickly those things that led to negative experiences. We often must remember after ONE bad experience. We don’t have the luxury of taking many repetitions to learn that a snake can be poisonous. Intense negative emotions burn events in to memory.

Humans are programmed to identify danger. Some hard-wired danger cues are: darkness, sudden loud noises, and being alone

Humans are also programmed that comfort and protection is found in: closeness, rocking, and stroking. Note that many of these are found in sexual activity, hence the difficulty at times in differentiating comfort and sexuality.

Trauma sensitizes the nervous system. Extreme, repeated and intermittent stressors are the most likely to result in sensitization (although single stressors may also). When the nervous system is sensitized, relatively small triggers in the present cause extreme survival-in-moment responses. Children "make mountains out of molehills".

Extreme stress without control is the most harmful. This was shown in rat experiments- some rats were shocked when they pressed a lever (had control); some were shocked when the other rat pressed a lever (no control). The experiment found that animals who do have control developed strengths, those who did not developed ulcers, lose weight, had compromised immune systems, become more sensitized to shock, and couldn’t recover. Stress with control leads to habituation (developing new skills and coping mechanisms). Stress with lack of control leads to sensitization (disorganized intensifying response, immobility).

We now know a great deal about the functions of different parts of the brain.
Our brain has three tiers: the Cerebral Cortex (Human Brain); the Limbic System/Diencephalon (Mammalian Brain or Midbrain); and the Brain Stem and Cerebellum (Reptilian Brain). We can refer to them as the Old Brain vs. New Brain. The old brain is the lower order systems, which are responsible for survival. They develop first, and are located in the more primitive parts of brain like the brain stem. The new brain is the higher order systems. It develops last, and gives us our flexible adaptive capacities. It is located in the cerebral cortex.

The pre-frontal cortex is created by a caretaker doing cortex-functions (care taking, safety, meeting needs, figuring out problems). If no one is doing these things, the cortex will be under-developed. The cortex is responsible for complex thinking, analyzing, and using cognition to control emotional impulses.

The amygdala screens for threats, adds emotional valence to events, and activates the danger response when an event is a change from what is expected and appears threatening. It compares in-coming data with laid down patterns- asking one question- does this data suggest danger? It activates an immediate response while sending the information to the higher brain for further refinement. It makes the body become more alert and look for more information. It gets bigger when it is used more.

The hippocampus is involved with retrieval of verbal and emotional memory. It gets smaller as amygdala gets bigger.

The cerebellum is responsible for balance and rhythm.

Low Road vs. High Road of Emotional Processing (Le Doux, 1998, 2002)

"Traumatic stress is about "survival in the moment". The brain processes stimuli that are potentially life threatening and translates this perception into life sustaining responses." (Saxe 2006)

The brain receives sensory input into the sensory thalamus. The brain starts processing the stimulus in two ways, which we can refer to as the "ow road" and the "high road". The low road utilizes the more primitive, older brain; the high road uses the more complex newer brain.

The Low Road

Stimulus/Trigger sent to Sensory Thalamus then to Amygdala yields Response

The Advantages of the Low Road:
It prepares body for an emergency response, and very quickly gives the organism info about danger. It is reflexive, unconscious, and does not contain contextual info. It sacrifices details for speed

Disadvantages of the Low Road:
It responds rapidly to incomplete bits of information. There is no context to the information. It facilitates memory storage in an incomplete way. This memory may produce flashbacks, which are "flashes of emotionally-laden memory." It leads to misperception of triggers and to overreaction, making mountains out of mole hills.

The High Road

Stimulus/Trigger to Sensory Thalamus to Amygdala and to Prefrontal Cortex to the Medial Temporal Memory System (Hippocampus) to the Sensory Cortex leads to a Response

A "Cognitive Wedge" is inserted between stimulus and response

Advantages of the High Road:
This type of processing leads to the most adaptive response in the moment. The high road pathway can maintain the low road survival-in-moment response if needed. With the help of our cortex (higher brain), we respond at a level appropriate to the level of danger. Determining the level of safety or danger via high road is also often unconscious and rapid. The cortex adds a context to the information, and (if appropriate) sends safety signals to the amygdala. The cortex facilitates memory storage in continuous complete way.

Parts of Cerebral Cortex Used in High Road Processing:
The sensory cortex retrieves and engages information from long term memories that contain experiences with similar stimuli (accurate perception). The medial temporal memory system (which includes the hippocampus) places the stimulus in the proper time and context. The prefrontal cortex puts information into the individual’s direct awareness for considered action to occur. The person inserts a "wedge of cognition" between the stimulus and the response.

What the brain does in danger (hyper arousal):

  1. Focuses alertness
  2. Shuts down cortex chatter
  3. Becomes more vigilant and more concrete
  4. Heart rate increases- blood sent to limbs
  5. Focuses on social cues- is help available?
  6. Muscle tone increases
  7. Hunger/digestion disregarded

When unable to fight or flee, a person is left only with the option to freeze. If action does not seem possible, the brain sends a "freeze" response to the body. This response too is self-protective. This response is related to later dissociative responses. It is common in infants and young children. It is more common in females than males. It is driven by the most primitive parts of the old brain. In the freeze response, the brain prepares the body for injury. This response is also graded and occurs on a continuum. The person has a sense that time slows and what’s happening isn’t real.

In the freeze response (dissociation) the person:

  1. Curls up
  2. Makes her self as small as possible
  3. Prepares for injury
  4. Blood is shunted away from limbs
  5. Heart rate slows to reduce blood loss from wounds
  6. Body is flooded with opioids ("brain’s heroin") to protect against pain which produces a feeling of calm and a sense of distance from what is happening (Some times this can help with functioning, such as a soldier functioning without feeling)

Fight/Flight AND Freeze
In both responses, the person has their foot on the gas and the brake at the same time.

Some Clinical Implications
Fight/flight (hyperarousal) often looks like AD/HD, hyperactivity, oppositional defiant disorder. Freeze (dissociation) look like inattention, spaced out, defiance to adults because child literally cannot respond.
Both hyper arousal and dissociation help people survive trauma. Both can be harmful if prolonged and habituated.
Flash backs and re-enactments may be seen as an attempt to have small doses of trauma within one’s control to develop habituation or tolerance. However, if trauma is too much it cannot be mastered this way.

Our brains have two halves. The right hemisphere handles the gestalt, the big picture, and initial impressions. It is responsible for negative emotions such as anger and anxiety. The left hemisphere takes care of details and analysis. It holds positive emotions. Generally the left hemisphere is larger; in children with trauma histories the right is larger. The corpus collosum connects the two, and it is smaller in trauma victims. Therefore, they experience less integration and generalization in learning. For example, a child works on methods for not fighting with his room mate, but he doesn’t think to use these methods to avoid fighting with another person.
Humans are hard-wired to seek attachment, especially when danger is present. The primary goal of attachment for humans is safety. However, we cannot forget that one method of engagement is aggression and provocation.

If there are persistent stressors in the early years of life, neurons do not grow and connect in prefrontal cortex, less inhibition is available.

Less developed pre-frontal cortex leads to:

  1. Short attention span
  2. Memory problems
  3. Distractibility
  4. Impulse control difficulty
  5. Social and test anxiety
  6. Poor judgment
  7. Hyperactivity
  8. Lying
  9. Problems reading social cues
  10. Poor organization and time management

Terror early in life can shift person to a less thoughtful, more impulsive, more aggressive way of responding to the world. Thinking has been shut down too much just when it was time for it to develop.

The brain develops a template that danger is normal. This could also contribute to under-reaction to danger: since brain is particularly paying attention to what is new, what doesn’t fit the pattern, danger is not new to this brain.

Also, researchers have identified a kindling effect in which a trauma survivor over-screens for danger, over identifies threats. This interferes with reading social cues, distorts his perception of others.

People with "good enough" childhoods have arousal/relaxation cycles and know ways to calm down. Trauma survivors start at a higher base-line arousal, have rapid spikes, and rely on the external environment to help them calm down. This leads them to have to do something to draw in external control (i.e. cutting).

Trauma victims have 40% higher prevalence of learning disabilities especially language: auditory processing and expressive language (Receptive/expressive language disorder). This may be due to under-development of both the cortex and the corpus collosum.

Trauma Damages the Ability to See into the Future
The ability to calculate the potential risks and benefits of an action is a very important human function, and to children growing up in abusive households it is essential and life saving. However, due to the unpredictable nature of events, the over-exposure to danger, and the struggle to survive, this ability will be compromised. The child may both over and under estimate danger, and also may over and underestimate potential pleasure. They may not be able to see any future for themselves.

Healing From Trauma
Moving to high-road processing also depends on environmental interventions to help remove triggers (when possible) and reduce risk of continued exposure to trauma. In addition, the environment must provide the child many "signals of care", which work to counteract the "survival-in-the-moment" crisis mentality.

Selected Resources: Trauma and the Brain
Perry, B. and Szalavitz (2006). The Boy Who Was Raised As a Dog. New York: Basic Books.
Perry, B. (2006). “Applying Principles of Neurodevelopment to Clinical Work with Maltreated and Traumatized Children.” In Webb, N.B. Working With Traumatized Youth in Child Welfare. New York: Guilford.
Saxe, G.N., Ellis, H.B., and Kaplow, J.B. (2007). Collaborative Treatment of Traumatized Children and Teens. New York: Guilford.
Vanderkolk, B.A. (1996). “The Body Keeps the Score: Approaches to the Psychobiology of Posttraumatic Stress Disorder.” In Vanderkolk et. al. Traumatic Stress: The Effects of Overwhelming Experience on Mind, Body, and Society.

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