A neurologist started a rather informal registry of soldiers with head trauma in 1967, and scientists have been been learning from these veterans ever since.

Fascinating!

By cataloguing the areas of brain damage in the veterans, and cross-referencing that information with data on their deficits and difficulties, Barbey, Grafman, and their colleagues have been able to map out the neural circuits involved in general intelligence, emotional intelligence, and social problem-solving. They recently discovered that many of the same brain areas—a network of structures in the frontal lobe and parietal cortex—underlie all three of these abilities. Historically, many psychologists have viewed general intelligence as separate from social and emotional intelligence, Barbey said. But these results fit with the more recent view that these skills are intertwined and interrelated. “The brain is not making a strong distinction between these forms of intelligence,” Barbey said.

And for all they have taught us about damage and destruction, these men are also a testament to the brain’s ability to recover from seemingly catastrophic injury. “If you just look at the CT scans and saw the amount of brain tissue missing, you’d say, ‘Oh my god, they’ll have to be in nursing homes,’ ” Grafman said. But many went on to have relatively normal lives. They got married and started families. Most went back to work. Some even stayed in the military. “They had their own impairments and deficits, but through a combination of motivation and will, and the care of their family and friends, the majority of them managed to reënter society,” Grafman said. One man, known as J. S., sustained a gunshot wound that obliterated most of his left hemisphere. He struggled with words after his injury but remained capable with numbers and spent many years living on his own, in a trailer by a lake.