Brains

Evolving Ourselves by Juan Enriquez and Steve Gullans. Inserting human glial stem cells into the brains of newborn mice enables them to learn faster. Electromagnets placed on the skulls of monkeys enhances their cognitive performance. We may soon be entering a new age in which human brains can be radically enhanced: "One of the many horrific consequences of a severed spinal cord is loss of bladder control. In 2013, a Cleveland team reattached severed mouse spinal cords through nerve micrografts. The procedure was so successful that not only did the animals recover some respiratory functions but even the ability to control areas much farther down their bodies, including their bladders. Such an operation makes it conceivable that a full mouse-head transplant might someday be successful. And if it was successful, we might begin to be able to test various hypotheses: If a mouse had learned in detail how to ask for food or navigate a maze, would the mouse's head take that knowledge to a new body? "No one has attempted a whole human brain transplant, nor should they. Nascent technologies and knowledge make the procedure far too risky and speculative, and the chances of success are minute, not to mention the ethical challenges of identifying and qualifying a donor. But as science progresses, if one became able to transplant a human brain or portions of a brain, then one could begin to answer some fundamental questions about the nature of consciousness, memory, and personality. ... "While we wait for full-brain transplants, there is still a lot of data flow; even mini transplants can make a huge difference. Because ethical constraints limit the kinds of experiments we can perform on humans, scientists get ever more creative at blurring the lines and distinctions between animals and humans. The most basic of human cells, stem cells, which program all functions in our bodies, are being inserted into species far and wide. As we blur species lines, as we 'humanize' parts of animals, we begin to see blind mice that grow human corneas. And because some of the organs and biological structures in pigs are so close to those of humans, there are more and more efforts to modify these animals' immune systems, humanize some of their organs, and transplant them directly into humans. technique for mouse head transplant "In an attempt to find cures for various neurological diseases, more and more human brain cells are entering animal bodies, which often results in significant and noticeable upgrades. Alzheimer's researchers found that transplanted human stem cells led to mice with improved spatial learning and memory. When one inserts human glial stem cells into the brains of newborn mice, the new cells grow and eventually overwhelm many of the original mouse brain cells. Soon you get mice that can learn much faster, retain memories longer, and whose brains transfer certain information three times as fast as normal mice. (Of note is that this latter procedure is transplant of glial cells, the cells that preserve, feed, and protect neurons. It is not yet a neuronal transplant, so while it is unlikely this kind of transplant would transfer memories, it does seem to significantly enhance cognition.) "If we can transplant human cells into animals' brains and significantly improve their cognition, it is also reasonable to think that one could transplant and develop enhancements to the average human brain; recent stem-cell transplants into Parkinson's patients' brains show some promise, albeit inconsistently. Whose brain cells we get, at what stage, through what procedures, may end up making quite a difference. (They may also give rise to a slew of ethical and access issues; would you want a transplant from an average brain or a genius brain?) As we continue to seek cures for various neurological diseases, we are likely to find more and more examples of interventions that significantly alter and enhance various brain functions. And this will give us more choices in how to enhance, evolve, and build up the most human of our organs. "Meanwhile, we are continually attempting to 'upgrade' our brains through electronic inputs, both internal and external. Sophisticated electromagnets placed on the skulls of monkeys can direct them to pick out any one of 5,000 random objects 10 to 20 percent more accurately than nonenhanced monkeys. Early tests on seven human epilepsy patients, through already-implanted electrodes, showed improved navigation through virtual mazes. Soon the 'handicapped' became better at this task than 'neurotypicals,' Human deep-brain stimulation will likely enter early clinical trials in 2015, to try to boost memory in Alzheimer's sufferers. But if techniques like this really work -- a big 'if' -- then they could be broadly deployed to enhance the memory of the species. ... "Drugs provide yet another path to enhance/modify human cognition. While we regularly approach a Starbucks vaguely hoping a triple shot of caffeine will upgrade our mental capacity, the effects of tea, energy drinks, and other caffeinated boosts are temporary. Modafinil may be different. A pill originally designed to help you sleep better, this drug may have the side effect of memory upgrades that last for significant periods. As we understand the biochemistry of the brain better, we will likely find more and more ways to boost, refine, and improve cognition, once again unnaturally altering the species. And then there is the external cognition option. Back at the MIT Boyden lab, they are busily building tiny computer chips, embedded with thousands of needles 1/1000th of an inch wide, which allow measuring, and perhaps altering, activity inside individual neurons."

Evolving Ourselves: How Unnatural Selection and Nonrandom Mutation are Changing Life on Earth Authors: Juan Enriquez and Steve Gullans Publisher: Penguin Group Copyright 2015 by Juan Enriquez and Steven Gullans