Learning causes structural changes in affected neurons
When a laboratory rat learns how to reach for and grab a food pellet — a complex and unnatural act for a rodent — the acquired knowledge significantly alters the structure of the specific brain cells involved, which sprout 22 percent more dendritic spines, connecting them to other motor neurons.
The finding, published in the journal Proceedings of the National Academy of Sciences by Mark H. Tuszynski, MD, PhD, professor of neurosciences and colleagues at the University of California, San Diego School of Medicine, underscores the brain’s remarkable ability to physically change as it learns (not just in rats, but presumably in humans too), but also reveals that the effect is surprisingly restricted to the network of neurons actually involved in the learning.
“I think it’s fair to say that in the past it was generally believed that a whole cortical region would change when learning occurred in that region, that a large group of neurons would show a fairly modest change in overall structure,” said Tuszynski, who is also director of the Center for Neural Repair at the UC San Diego and a neurologist at the Veterans Affairs San Diego Health System.
