Neuroscience was my favorite course in my graduate program for speech-language pathology. Historically, the workings of the brain and nervous system have been cloaked in mystery. In recent decades, however, scientists have made remarkable progress in terms of illuminating neural physiology and function. The book Maximum Brainpower by Shlomo Breznitz and Collins Hemingway explains our evolving understanding of neuroplasticity and the way in which we can use it to our advantage to maintain cognitive sharpness throughout our lives.
Neuroplasticity is the brain’s ability to adapt. This adaptation occurs through the creation of new synapses (connections) between brain cells, changes in the composition of messenger chemicals, and generation of new brain cells. In the not too distant past, common wisdom was that the brain did not adapt after childhood. Even the most laureled scholars insisted that once we passed adolescence our brain’s ability to generate new brain cells was lost. In that model, the only hope for maintaining mental sharpness into old age was to forestall the inevitable slow death of our current fund of brain cells. We now know that brain cells and their synapses continue to evolve and regenerate throughout our lives. This seminal discovery has by necessity changed our perspective on cognitive health.
What the authors of Maximum Brainpower teach us is that our brain’s regenerative capability responds specifically to the challenges (or lack thereof) that we provide it with. In this regard, the brain is similar to skeletal muscle in the body. Older people can maintain a high level of physical fitness and muscle mass, but only if they work consistently through exercise to ensure that the body continues to produce the muscle mass and metabolic materials to support it. Similarly, the brain requires mental effort to maintain its function.
Breznitz and Hemingway do a nice job explaining the ways in which our brain has evolved to avoid the heavy lifting associated with maintaining mental acuity. In Chapter Three, “The Many Dangers of Experience,” they help us understand the ways in which humanity’s environment has changed throughout history from one in which the vast majority of our effort was put into survival tasks to one in which the challenges are varied and less concrete. In this chapter, the authors build a case for why experts in various subjects often fail to respond adequately when new circumstances require an unfamiliar response. It was fascinating to consider the ways in which our experiences can lead us into a pattern of rote reactions and that we can fail to recognize the need to change them.
In Chapter Six, “The Font of Cognitive Fitness,” Breznitz and Hemingway deconstruct research in the areas of intelligence and cognitive fitness. I found their discussion of cross-sectional versus longitudinal studies to be quite useful in untangling the conflicting results found between major studies. Understanding that cohorts of people may have had similar influencing factors in their cognitive development over the course of their lives goes far in explaining why some discrepancies appear to be age-related, when in fact they are generationally based.
For readers interested in learning the mechanics behind neuroplasticity, Chapter Nine, “The Way the Brain Changes and Grows,” provides good insight. In this chapter, they also mention some of the research that has been done with people who have experienced strokes. In the realm of speech-language pathology, there has been increased interest in and application of what is referred to as constraint-induced therapy. This approach involves preventing the patient from using compensatory strategies and setting up the task such that they must provide a direct verbal response. Chapter Nine informs the reader why this type of therapy works, even though it appears to be counter-intuitive.
Toward the end of the book, the authors become somewhat more philosophical. One passage from Chapter 16, “Too Ancient for Our Lives,” reads, “We need to invest in cognition because the world is running away from us as a species.” The thesis Breznitz and Hemingway propose by the end of the book is that humanity has created an environment for itself that is out of sync with the way in which the brain developes. We have created a world where there is too much change, happening too quickly and where much of our needed mental challenges have been usurped by the efforts of electronic devices. They express the similarity between the way in which we now need to include physical exercise into our day because it is not required in the course of our work and our current need to incorporate mental exercise into our day, because of our increased need for cognitive flexibility and speed.
Each of the chapters in Maximum Brainpower is a cogent and well-constructed essay on one aspect or another of cognitive and/or brain function. The weakness of this book, however, was that I did not always feel there was a solid through line with discernible segues between the chapter topics. Therefore I feel the authors’ message was somewhat more diffuse than perhaps it was meant to be. In addition, the subtitle of the book, “Challenging the Brain for Health and Wisdom,” raised an expectation for me that the book was going to include specific task suggestions and exercises to approach cognitive fitness, but this was not the case. In this regard, the weaknesses of the book appear to be more expectational than literal.
Maximum Brainpower is readable for a non-scientific layperson and yet manages to communicate a great deal of scientifically accurate information. Readers who are interested in separating the truth from the bunk in terms of our more recent understanding of brain science will find Maximum Brainpower to be a satisfying read.