Neural Plasticity: “Change Your Brain” part 2

Continuing with my overview of Sharon Begley’s book Train Your Mind Change Your Brain, I’d like to proceed toward a discussion about the human implications of neuroplasticity research. In the last post, we left off with the realization that the human brain is a malleable system whose functionality is patently not fixed by genetic predeterminsim: regions such as the visual cortex which would normally process visual information are commandeered, for example, by the tactile sensations in blind Braille readers in order to create enhanced sensitivity in discrimination of fine touch.

As the paradigm of the non-deterministic human brain began to emerge, a major question that naturally came to the fore is whether or not an adult brain—one that has already gone through its most dramatic periods of development—could or could not manifest significant physical change based upon experience. Two sets of experiments serve as clear illustrations to the affirmative. In a PNAS-published study comparing the brains of London cab drivers to non-cab driving control subjects, it was demonstrated using structural MRI that the hippocampal brain regions—involved in spatial memory and orientation—were significantly enlarged in the

The Death of Genetic Determinism?

I’m currently reading Sharon Begley’s fantastic book Train Your Brain, Change Your Mind, and wanted to take a few posts to summarize some of the concepts articulated throughout the book’s pages. Melding both science history and an optimistic vision of humanity’s potential, Begley’s book is a veritable ode to the phenomenon of neural plasticity.

The term neural plasticity refers to the capability of the brain to physically rewire and to, quite literally, become a new brain. Establishing neural plasticity as a scientific fact has been an arduous battle that has taken decades of work and that has fought head-on against previously prevailing scientific dogmas. For much of the twentieth century, the dominating doctrine of neuroscience was that once a baby is born, the neurons that are in the brain at the time of birth are all that there will ever be—there are no new brain cells that came into being in that individual from that point forward. This assumption, however, was invalidated by a conglomeration of clever experiments. One of the earliest of these crucial studies was a paradigm that tracked radiolabeled thymidine in the bodies of primates. In other words, thymidine—one of the