STRESS IS considered bad, though inevitable in today’s society. Usually, stress is supposed to be an inhibitor, disrupting human performance across various sensory modalities, including attention, learning, memory and other complex higher mental processes. But not all stress is bad. Based on his own researches and other neuro-cognitive experiments, professor Ian Robertson establishes in his book, The Stress Test, that the role of moderate stress across a lifespan is not only positive, but acts as a protective cover against disorders like dementia and many other psychosomatic abnormalities. Yes, good stress is not an oxymoron. In the book, Robertson argues that a moderate amount of stress can be beneficial and can increase our productivity. The difference between good and bad stress lies in our response. Robertson cites Nietzsche’s famous maxim in the book, “what does not kill me makes me stronger” to explore the right level of challenge and stress that can help people flourish.
There is an interesting case study in the book about London taxi drivers. As per the study conducted by researchers at University College, London, it was found that the part of brain called hippocampus has expanded in London taxi drivers. Unlike taxi drivers in many cities, who are often incomers with a scanty knowledge of the locality, London taxi drivers have to pass something called ‘the knowledge’ test, which entails memorising the entire street map of London and all possible routes and shortcuts. To become a London taxi driver as of 2015, they must spend two years learning and then be tested for knowledge of the enormous metropolis. Hippocampus is the key structure that fails in Alzheimers. It is the crucial part of the brain for laying down new memories. A person with the disease usually has less problem remembering things that happened years ago, but will forget what was said or happened a few minutes before. In case of taxi drivers, the rear part of the hippocampus had grown and, in fact, kept growing three months after the exam ended. The researchers concluded that learning remodelled the brain more surely then any neurosurgeon could.
People who endured some type of stress, such as serious illness of a partner, conflict with family or even sexual abuse, were found cognitively sharper than those who hadn’t. For example, sexual abuse at an early age sentences most people to a lifetime of self-exploration in an attempt to come to terms with what had happened. This is like massive rewriting of the software of the self. This constant exercising and self-reflection act as powerful mental stimulation.
Through the course of the book, Robertson identifies various factors that determine the body’s positive response to stress such as education and social circles. During a study of identical Swedish twins, it was found that one pair had dementia, while the other was normal. Among the normal twins, the common factor was education. The majority continued their education. This effect of learning and education on dementia has been given the name ‘cognitive reserve’. Indeed, people with higher cognitive reserves have thicker layer of grey matter in the cortex and many more brain cells per cubic millimetre. Another factor that increases the grey matter is friends and family. Contact with children, friends and family was seen to reduce the risk of dementia among elderly significantly. It isn’t just the number of years of education you have when you are young that strengthens your cognitive reserve, but also continuing to use your brain in the old age and having a rich social network.
Stress has a similar impact. When we face a challenge or any kind of stress, our brain releases noradrenaline to help sharpen our perception and decision-making process. However, one obvious factor is the degree of stress. While challenge smartens you, too much stress can make you dull. Therefore, really bad things like losing a child could crush someone. But different people react to the same stress in different ways. Some see it as a threat and some as a challenge. To explain who would react in which way, Robertson concludes that stress can only ever be ‘good’ for someone when they retain some control. So yes, what doesn’t kill you can make you cognitively stronger, and thus a better problem-solver, provided you have some sense of control over your life. However, there is a caveat. Too much stress for too long certainly does not strengthen us.