In this Q&A, neuroscience professor Michael Merzenich, PhD and Chief Scientific Officer of Posit Science explains why brain health is receiving increased attention, the signiﬁcance of new breakthroughs in neuroscience and actual and potential ramiﬁcations of these advances.
Q: For years we’ve received advice on the importance of having a healthy heart. Recently, we have been receiving similar advice about brain health.
Michael Merzenich, PhD (MM): Well, the heart is a vital organ and deserves the attention. But brain health is equally important. The brain grows and sustains our human abilities, and its problems are expressed as our disabilities. The brain defines us, after all, as the person that we are. Have you ever witnessed the slow deterioration of a loved one with Alzheimer’s? If so, you have watched the person that you knew and loved slowly fade away, even while their body may have remained relatively healthy.
Q: So why is the brain getting more attention recently?
MM: Scientists used to believe that the brain developed all of its major functionality—that is, the "wiring" of the brain that supports hearing, seeing, feeling, thinking, emotions and the control of movements—in early infancy. The "mature" brain was thought to be unchangeable, like a computer with all its wires permanently soldered together.
However, there has been a recent revolution in our thinking. We now know that the brain is constantly revising itself. Physical brain change occurs every time we learn something new. This new ﬁnding—that adult brains are malleable—has far-reaching implications for our understanding of brain ﬁtness. We refer to this capacity for continuous physical, chemical and functional brain change as "brain plasticity" or "neuroplasticity."
Q: How does neuroplasticity, or the brain’s ability to rewire itself, relate to brain health?
MM: In the case of aging, the plasticity of the brain can have negative consequences. The brain of the average mature adult actually shrinks, as the brain machinery supporting hearing, seeing, feeling, thinking, emotion and movement control degrades over time. These changes occur to a large extent because mature individuals are less likely to use their brains in the speciﬁc ways that are required to sustain our cognitive abilities. In the case of other neurological and psychiatric conditions, such as schizophrenia or Parkinson’s disease, large-scale neuroplasticity actually plays a powerful part in distorting the brain’s chemistry and ability to function. On the brighter side of the equation, the breakthrough in neuroplasticity research has revealed strategies by which we can restrengthen the brain’s functionality.
Q: What types of strategies can we use to restrengthen the brain’s functionality?
MM: We need to constantly use and develop our brain’s machinery through learning. This does not mean academic learning (although that is always useful). It means practicing targeted activities that engage the senses and our memories, and that involve the production of reﬁned movements. By applying the breakthroughs in neuroplasticity to develop brain health tools, scientists can help people maintain—and possibly restore—their cognitive abilities.
Q: What types of activities can engage the senses and memory?
MM: To keep our senses and memory healthy, it is very important that we spend time each day in intensive, effortful learning that requires our close attention. Under these conditions, our faculties can be remarkably well conserved. For example, professional musicians can sustain high abilities at their craft until the end of life, but only if they practice almost every day using an intensive and closely attentive learning strategy. Their careful listening, precise movement, and accurate reading and complex memory practice is essential for sustaining their great skills. If a violinist in an orchestra does not practice intensely over a period of a month, other musicians around her will begin to ask "What’s wrong with Susan?"
Q: In essence, we need to exercise our brains?
MM: Absolutely! Maintaining a healthy brain requires that we all have to work hard to sustain the crucial abilities that deﬁne what we can and cannot do, that support the person that we are.