Findings, published in Nature, could lead to improved treatments for stroke, other brain injuries.

Learning a new skill is easier when it is related to an ability we already have.

For example, a trained pianist can learn a new melody easier than learning how to hit a tennis serve.

Neural engineers from the Center for the Neural Basis of Cognition (CNBC)—a joint program between the University of Pittsburgh and Carnegie Mellon University—have discovered a fundamental constraint in the brain that may explain why this happens. Published as the cover story in the Aug. 28, 2014, issue of Nature, they found for the first time that there are constraints on how adaptable the brain is during learning and that these constraints are the key determinant for whether a new skill will be easy or difficult to learn. Understanding the ways in which…