My summaries of the book Brain Rules continue...
Chapter 8: Stress
Rule #8: Stressed brains don't learn the same way.
What is stress? Medina mentions research that identifies stress with three simultaneous factors. First, a person will experience an aroused physiological response measurable by an outside party. Second, the thing causing the stress must be perceived as aversive. Finally, the person experiencing it will not feel in control of the stressor.
The body's response to stress was meant to address situations that lasted for seconds--like getting away from a saber-toothed tiger. The body releases adrenaline. It also releases a hormone called cortisol that kicks in with extra power. The problem is chronic stress, when the system does not return to normal. Our arteries get damaged, develop scars, and clog. Our white blood cells and immune system are weakened and we get sick more easily.
In an instant, stress greatly improves our memory. But prolonged stress cuts our memory and ability to make decisions by as much as 50%. Cortisol disconnects neural networks and kill cells in our hippocampus, the part of our brain that works to form long term memories.
A protein called BDNF counteracts the force of the cortisol, but chronic stress can completely shut it off to where you won't even remember a traumatic event. It can bring a debilitating depression that does not even try to escape a situation when it could. Some people can handle stress better than others. But at some point, stress becomes toxic, what the researcher Bruce McEwen calls the "allostatic load," the tipping point when your body begins to lose to stress.
The rule of this chapter is that "stressed brains do not learn the same as non-stressed brains" (184). They don't do much learning at all. "One of the greatest predictors of performance in school turns out to be the emotional stability of the home" (183). "Children living in high-anxiety households would not perform as well academically as kids living in more nurturing households" (184). For example, it is not divorce per se but overt conflict in a home that predicts grade failure.
Stress is an enemy of the work place too. Depression kills problem-solving abilities. It drastically increases health care costs. It often leads to firing, requiring the need for training new workers. The type of stress in the workplace, the employees home life, and the balance between stimulation and boredom determine whether a workplace is stressful. One of the worst formulas for workplace stress is when much is expected of a person but he or she does not have control over the outcome.
Medina ends the chapter as usual with some ideas. The stability of a home is so crucial to the learning of a child that parental training to reduce stress on children would be ideal. Medina would make education a "family affair" from a week after birth. Since the typical time of having children and some of the most productive work years for a person coincide, Medina's perfect world would see child care at places of work and marital training to help new parents cope with the new found stress of a new child.