Hébert declined to describe the session, which he said was not recorded “out of respect for those who preferred discretion.” But he’s in favor of growing non-sentient human bodies. “I am in conversation with all these groups because, you know, not only is my brain slowly deteriorating, but so is the rest of my body,” says Hébert. “I’m going to need other body parts as well.”
The focus of Hébert’s own scientific work is the neocortex, the outer part of the brain that looks like a pile of extra-thick noodles and which houses most of our senses, reasoning, and memory. The neocortex is “arguably the most important part of who we are as individuals,” says Hébert, as well as “maybe the most complex structure in the world.”
There are two reasons he believes the neocortex could be replaced, albeit only slowly. The first is evidence from rare cases of benign brain tumors, like a man described in the medical literature who developed a growth the size of an orange. Yet because it grew very slowly, the man’s brain was able to adjust, shifting memories elsewhere, and his behavior and speech never seemed to change—even when the tumor was removed.
That’s proof, Hébert thinks, that replacing the neocortex little by little could be achieved “without losing the information encoded in it” such as a person’s self-identity.
The second source of hope, he says, is experiments showing that fetal-stage cells can survive, and even function, when transplanted into the brains of adults. For instance, medical tests underway are showing that young neurons can integrate into the brains of people who have epilepsy and stop their seizures.
“It was these two things together—the plastic nature of brains and the ability to add new tissue—that, to me, were like, ‘Ah, now there has got to be a way,’” says Hébert.
“I just prefer life over this slow degradation into nonexistence that biology has planned for all of us.”
One challenge ahead is how to manufacture the replacement brain bits, or what Hebert has called “facsimiles” of neocortical tissue. During a visit to his lab at Albert Einstein, Hébert described plans to manually assemble chunks of youthful brain tissue using stem cells. These parts, he says, would not be fully developed, but instead be similar to what’s found in a still-developing fetal brain. That way, upon transplant, they’d be able to finish maturing, integrate into your brain, and be “ready to absorb and learn your information.”
