Brain Plasticity

During the growth and development of the brain, the physical structures and neural pathways of the brain can change dramatically. Various regions of the brain may grow, new synapses may be created, or unused synapses may be pruned off. The ability of the brain to change and adapt has been called plasticity. In the TED talk “The Growing Evidence of Brain Plasticity”, Dr. Michael Merzenich makes a case for brain plasticity and proposes ways this ability can be used to help various mental disorders. In order to fully appreciate Merzenich’s talk, it would be helpful to know a little bit about the nervous system, especially synaptic connections. In the example of plasticity in monkeys, Merzenich discusses the change of cortical areas when a monkey
learns a new task. As the monkey learns the task, the different neurons that are involved in the production of the task can begin to form specific connections with each other. The axons and dendrites of the neurons in CNS and PNS responsible for the physical movement, the cognition and interpretation of the movement, and the memory of the movement can form physical synapses with each other until the movement becomes mastered. Background information from biopsychology, like what a synapse is and what neurons in the different brain structures can accomplish, helps clarify Merzenich’s heavily scientifically worded points. While on the TED talk, Merzenich mentions two periods of time where we see physical change within the brain.
The first period, dubbed the Critical Period, occurs in the first year or so of life. This is the point in time where the brain takes in massive amounts of stimulus and starts to set itself up for more advanced processing later in life. Before a child can learn language, they need to learn sound, and before a child can walk, they need to learn the feeling of the floor underneath them. During the critical period, tremendous amounts of new synapses and growth must be done to create the correct connections and shortcut for more specific learning and skill development to happen once the child grown a little more. The other period of time that Merzenich mentioned extends throughout the rest of our lives. Brain plasticity is not just reserved for a growing child or adolescent. Mastering any new skill or even just experiencing or learning new things anytime in life can change the brain physically. For example, when learning a new skill, new synapses can be built in the appropriate part of the brain or body for you to remember and perform the skill better and faster. The ability and memory of the brain are practically boundless if the brain can refine its neurons, synapses, and pathways
properly. Finally, Merzenich applied the idea of brain plasticity as a way to diminish and treat learning problems in children and memory problems in the elderly. Merzenich argues that problems like these are caused by “noise” in the brain. These brains are not the efficient machines they were designed to be; different physical strategies and pathways have caused the brain to function in a less than optimal manner. Assuming that these problems come from abnormal neurology, the neurology of these noisy brains can be normalized through appropriate stimuli. Through neuroscience based training and the plasticity of the brain, the appropriate connections and pathways can be made for a child to become a proper receiver and user of language or for the elderly to encode and process memories. I was personally most interested in the way Merzenich described the specialization of brain.
He noted in his talk that we all basically start out with the same brain, but the differences in our environment and experiences shape that brain to be unique. We are constantly receiving stimuli and the way we receive, interpret, think, and react to that stimuli changes who we are and how we will interact with other stimuli later. The brain is intended to select and specialize in the most appropriate and effective way to handle your unique environment. And plasticity allows you to constantly adapt as your situations and environments change. Overall I think the concept of brain plasticity is a wonderfully useful concept and is something to keep an eye on. In an advanced society where we are trying to optimize cognition and keep the brain in working order for as long as possible, it would be beneficial to understand the connection between our biology, our psychology, and the how they affect each other. As Merzenich mentioned at the end of his talk, if they physical part of our brain is so important to our overall well-being and healthy psyche, we need to start exercising that part of our body and using its plasticity to change it for the
better.