Boy without one-sixth of his brain is a remarkably 'normal' 12-year-old

A boy who had one-sixth of his brain removed to stop daily seizures now acts like a typical 12-year-old, according to researchers and his parents. 

Tanner Collins from New Stanton, Pennsylvania, was six years old when he had a tumor in the right hemisphere of his brain removed. At the time, his family was unsure if it was benign or malignant. Before the surgery, his parents, who are both nurses, felt they had exhausted options to rid him of frequent seizures. The anti-seizure medications were also taking their toll on Tanner's personality, behavior, and performance in school, his parents Carl and Nicole Collins said. 

A possible side effect of the surgery, which would remove a sixth of his brain: He might not recognize his parents' faces. 

It was a risk they were willing to take for his health. The tumor was in fact benign, not cancerous. And, to their relief, their son Tanner recognized his loved ones when he woke up. 

He was left with a visual impairment that he learned to cope with in recovery. His parents said he often "ran into things." 

But, he progressed quickly and experts observing his case realized his brain was making a remarkable compensation for the part it lost, as detailed in a study in the peer-reviewed journal Cell Reports. 

Marlene Behrmann, a psychology professor at Carnegie Mellon University and lead author of the study, assessed Tanner's brain and behavior from age 7 to 10. 

"This is the first longitudinal study of the organization of the brain in a young boy who has had a third of the right hemisphere of the brain removed," she told USA TODAY.

During five check-ins over those years, Behremann tested Tanner's ability to recognize words and faces, the primary function of the missing parts of his brain. 

"These are very difficult visual tasks," she said. "The visual system has to be really competent."

Tanner's results were compared against other children his age with complete brains. Fifteen children were a part of the behavioral group and 12 children were a part of the brain imaging group, Behremann said. 

Researchers found that Tanner's brain was able to compensate for the lost area, picking up recognition functions in his left hemisphere.  

"His development is fantastic," Behremann said. 

Tanner does have what researchers call a "blindspot" in his vision, which doesn't affect daily life but will not allow him to drive a vehicle in the future. 

Tanner's parents say people who meet their son can't tell he's had surgery to remove part of his brain at all. Tanner, now 12, is an honor roll student who enjoys playing volleyball, video games, swimming and camping. He's also a part of Boy Scouts of America, his parents said.

Through it all, his family is also amazed at his positive outlook. Carl and Nicole Collins said their son is more self confident now than he was before surgery. 

"I am grateful for my family and my doctors," Tanner said. 

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