The Importance of Stress
Every teacher who works in difficult areas has had the experience of a student losing control of their behaviour for no apparent reason. The catalyst might be something as simple as raising your voice at a boy who arrives late for class and interrupts the lesson; an all too familiar episode. The child starts off by answering back and quickly escalates into swearing at the teacher and in some cases violently throwing chairs. This intensification of dysfunctional behaviours corresponds to an increasing level of stress experienced by the student. The thing is, the intensity of the outburst is not related to the incident. This disproportionate reaction to a relatively minor indiscretion by students with a history of abuse and neglect is driven by their damaged fear response, linked to a previously stressful experience. The understanding of stress is critical for coming to terms with the human condition and understanding this process will clarify our approach to dealing with these damaged children and similar situations in the classroom.
Stress is the fuel for all brain activity and it is the brain that drives behaviour. It must be recognised that the brain’s only capacity is to initiate movement by engaging muscles to move body parts or activate chemicals to generate changes to our biology; things like the infusion of cortisol or adrenaline. There is a strong acceptance of what stress is, it is an electro/chemical response to a person’s environment that fuels a bodily response.
Much has been written about the importance of stress, after all we would not move if it was not there to drive our behaviour. Moderate, predictable stress prepares us to cope with the general world. Sports coaches and teachers are familiar with the following diagram. This illustrates how we need an optimal level of stress to perform at our best.
If our level of arousal is too low we underperform, too high and we get the same result. For a teacher the trick is to hit the goldilocks-spot, get the arousal just right. The difficulty is that for thirty students there are thirty different curves. What will optimise on one student might barely engage another or terrify a third. It is obvious that for children who have been severely neglected or abused it is their inability to control their level of arousal in the wake of the teacher’s efforts to engage them in the lesson that creates the dysfunctional behaviour. They are most likely to be on either end of the arousal scale and their learning will be minimal.
Almost exclusively the stress phenomena has been studied when something in the environment threatens survival. This is the ‘flight/fight/freeze response to get the body into a state of readiness to protect itself from harm. In these cases the body produces chemicals including cortisol, epinephrine, and norepinephrine. For our work, helping teachers deal with students with severe dysfunctions, this focus on protection is pertinent. However, understanding the process that initiates stress helps with a better understanding of why we advocate our approach to behaviour management, the manipulation of the classroom environment.
We accept that, like all biological species we are driven to survive and reproduce in the environment in which we inhabit. We have needs that must be satisfied from our environment to maintain our existence and it is this balance between what we need and its availability that regulates our level of stress. This balance is referred to as our point of homeostatic equilibrium, that is all our needs are being satisfied. Of course, we can never remain in this state for long. Our demands from the environment are constantly being renewed. Take the example of our need for oxygen, when we breathe in we are satisfied but if you stop breathing you soon fall into a state of disequilibrium and you experience stress at increasing levels. If conversely, the environment you are in, say underwater and you can’t readily breathe you experience the same stress response.
This life-threatening comparison between our need and the external world is stark. However, as a species we have learned to control much of our environment most of the time. Unlike many other species who are born with their behaviour requirements intact, a critical feature of human infants is that they have to learn much of the behaviours required. It is the early childhood environment and the lessons taught that will significantly influence subsequent levels of stress and driven behaviours. This comparison between observed conditions takes place in the cerebellum. The cerebellum is often referred to as ‘the little brain’ because it looks like the whole brain with two hemispheres that sit each side of a central line, located above the brain stem and behind the midbrain. Although it only occupies 10% of the brain’s volume it contains half the brain’s neurons.
The schematic model presented below explains how the cerebellum makes this comparison between observed and expected conditions.
External perceptions come into the cerebellum in a general sense via the thalamus, these are observations of the environment through our senses, touch, smell, sight, etc. These inputs enter via attached climbing fibres that inform the purkinje cells, large neurons with many branching extensions that is found in the cortex of the cerebellum. Of all the thousands of perceptions there are of the environment we ‘attend’ to those that suggest conditions that represent an opportunity or threat. How this comparison is made is from previous experiences, as I mentioned above, the brain can only initiate movement however, the brain’s genius is its ability to predict, to predict what will happen when threats or opportunities occur in the environment. These predictions are founded in our memory, internal schemas of what happened before.
The process is as follows, through our senses we observe the environment. When we perceive a threat or opportunity this is referenced back into our memory. These memories come into the cerebellum via the mossy fibres and on to the granular cells. It is this interaction between the granular cells and purkinje cells that determines the level of stress. If we have a history of easily dealing with the environment there will be negligible stress. However, if we have either no memory of a condition or it is a situation that we have never been able to successfully resolve then the stress levels will be elevated. It is this last set of conditions that sheds light on why early, systematic childhood abuse leads to post traumatic stress disorder (PTSD). This will be discussed in detail in a later Newsletter but for now it is the creation of the memory that is significant.
It is the cerebellum that identifies the discrepancy but it is the amygdala that initiates the fight/flight/freeze response by the production of the neurochemicals mentioned above. This response produces feelings ranging from anxiety through to terror. If a child experiences high levels or prolonged fear their amygdala becomes more ‘efficient’ at recognising potential conditions of which to be fearful. As mentioned in a previous Newsletter the amygdala of children subjected to abuse and/or neglect is significantly increased in size.
The result is that the neural pathways become so fine-tuned anxiety and fear become the normal conditions and the potential for positive pathways are excluded. Of all the debilitating consequences of this physical injury the one that most frustrates those trying to work with these children is that they become unable to respond to nurturing and kindness.
Because of the urgency to deal with situations that generate the fear response the initiation of the amygdala impedes the messages from the cerebellum from reaching the hippocampus and the frontal lobes. Because this cognitive arrangement of our brain is denied access the child is unable to make a more calculated assessment of the potential of maltreatment (the diagram below is a modification of the work of Joseph LeDoux an American neuroscience who specialises in the fear response). This is why so many of the behaviour management programs employed by schools and mental health professionals fail when the child is stressed, their strategies are cognitively unavailable at that time.
As can be seen in LeDoux’s model when the stimulus comes in and is assessed in the cerebellum it goes to the thalamus, the distribution point for the presenting circumstances. If it is a high threat it goes to the amygdala, the need for an immediate response is critical. If, on the other hand conditions are not menacing the incoming message will go both to the amygdala and the hippocampus. There is a link between these two but this is never effective in the short term. For example, people who become trained in contact sports such as boxing can be conditioned to suppress the fear response when an opponent is throwing a punch at them.
Although experiences with high emotional content do generate a fear response they also create memories and remembering that the brain is a predictive system we can generate the fear response with our imagination. If we think some abusive event might happen we become anxious, if we witness something that reminds us of that abusive incident we will re-experience that fear response. These memories are foundational to anxiety, neurosis and paranoia not to mention PTSD!
This is the first of a series of Newsletters dealing with stress, its causes and consequences for students. Our approach to managing students who have been exposed to early childhood trauma is underpinned by this knowledge and why we focus on the control of the classroom environment.