Perhaps, then, we should be looking in a different place: at the environments that children inhabit before they even enter the school gates. The effects of stress upon young children have been most famously outlined in Felitti’s 'Adverse Childhood Experiences' research, at the turn of the twentieth century. Families who live in socio-economically deprived conditions, in which ongoing poverty and its associated insecurity frequently experience a complex, interrelated and circular set of stressors within the household. In 2009, Jensen proposed an effect he dubbed “Cognitive Lag.”
Children raised in poverty... are faced daily with overwhelming challenges that affluent children never have to confront, and their brains have adapted to suboptimal conditions in ways that undermine good school performance.
Jensen 2009 online.
But how does this actually work in practice? The neurological evidence suggests that stressed children’s brains cope with a much heavier load than those who live within less difficult environments. A basic analogy can be made with an old PC getting slower and slower as it becomes overloaded with files. Children who live in households where insoluable problems constantly arise use cognitive resources to process these, and consequently, have less ‘mind space’ to give to other things, including learning.
In the early 2000s a range of research found that when infants were placed in stressful environments, they were likely to exhibit abnormally raised levels of the stress hormone cortisol. The action of cortisol in the body mobilises the 'fight or flight' response, during which the body's glucose stores are made available to the creature's muscles to either fight or flee, hence cortisol disturbances in young children can consequently lead to suppressed growth, anxiety, depression and less memory capacity available for intellectual development, as resources are diverted elsewhere to cope with what the brain processes as immediate ‘threat’.
It is useful to imagine stressful experiences as a cumulative 'load'. Some amount of stress is a normal feature of human life and can prevent boredom and inertia. But constant stress, particularly rooted in ongoing, unaddressable problems, particularly paired with low levels of physical activity, can severely impact upon human beings' internal resources, causing them to become chronically anxious. Long term anxiety can in turn become a contributing factor to physical and mental illness.
This is currently the situation in which nearly a third of children live within the UK; 34% of all children are officially categorised as living in ‘poor’ families, and proportionally, children are the most disadvantaged demographic group. Poverty is unequally distributed around the UK with higher concentrations in inner city areas; for example 55% of children in the London Borough of Tower Hamlets are officially designated poor- the majority of children who live in the area.
So what actually happens in the brains of children who live under significant stress? Recent research in neurophysiology is beginning to reveal how the brain responds to stress, and why it creates such problems for the processes of learning.
The main brain structures that are affected by the chronic secretion of stress hormones during childhood (hippocampus, prefrontal cortex and amygdala) are differentially involved in various cognitive functions (e.g., memory, emotion regulation, encoding of emotional memories). High cortisol levels have been linked to poorer ‘executive functioning’ across three cognitive domains: self-control, flexibility and emergent metacognition (the ability to reflect on one’s own thoughts).
Executive function is an umbrella term that refers to:
-The functioning of working memory, which impacts on the capacity to retain and manipulate information over short periods of time.
-Inhibitory control which includes the ability to pause and think before acting.
-The agility of cognition that underlies the ability to ‘multi-task’ in an organised fashion.
The initial calibration of the stress response system occurs in the early years of life, rather as one might set up a new central heating system. If the thermostat is set to ‘max’ at this point, that puts a great stress on the whole system, particularly the ‘boiler,’ which will quickly become liable to breakdown. High levels of cortisol within the brain increase the cognitive load, as resources are drained by a constant state of hypervigilance, which impels the individual to continually scan for evidence of threat. The mind therefore has reduced capacity for other, less biologically important functions, for example, maintaining on-task focus on school-based activities.
No amount of extra input can compensate for a brain that is too loaded with stress to learn, and in fact, it may create precisely the opposite effect, actually increasing the stress that is impacting upon the child’s daily life. The indications are, therefore, that we are looking in the wrong place for solutions, and imposing the wrong remedies.
The answer to under achievement amongst deprived populations does not lie in further increasing the cognitive load upon children in the school years, but in decreasing the source of that load in the early years of life. And the most direct way to do that is to ensure that families with small children do not become emotionally unstable pressure cookers in an ongoing struggle to achieve social, emotional and physical equilibrium below the poverty line.
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