Some people with half a brain have extra strong neural connections!

Half a brain can do a full-time job, a detailed study of six adults who had half their brains removed as children to treat severe epilepsy shows how brains can reorganize and recover. Despite how extreme the surgery is, many of these people maintain or regain their language and thinking skills. In a new study, researchers discovered a way the brain could compensate.

While the six participants rested in an MRI scanner, the researchers measured blood flow in seven brain regions that handle functions such as vision, attention and movement. In the experiment, blood flow served as an indicator of brain activity. When activity in one part of the brain changes in unison with activity in another, it implies that the regions are working together and sharing information. These are signs of strong connections, which are believed to be crucial for a healthy brain.

In the six people who had undergone hemispherectomy, these seven brain systems appeared to function normally. In fact, the connections between those seven systems were even stronger than those connections in six whole-brained people, the researchers report. Such stronger-than-normal connections could help explain how these post-op brains make up for missing parts, the researchers suspect.

Understanding more about how the brain reorganizes after a big change could lead to new approaches to speed recovery for people with common brain injuries.