Being called a brainiac may be a compliment but when it comes to gray matter, a person can have too much of a good thing. Scientists at University College London recently conducted a study that links high levels of distractibility with an increased volume of grey matter in the brain's left superior parietal lobe.
The reasons for this are not yet fully understood, but it might have something to do with the way the brain pares away excess neurons as it matures in order to more effectively carry out certain tasks. The brains of adults who suffer from attention deficit disorder may have failed to complete this process, and the connection may also help explain why children tend to be more easily distracted.
Source: National Geographic