More than any year before, 2012 was the year neuroscience exploded into pop culture. From mind-controlled robot hands to cyborg animals to TV specials to triumphant books, brain breakthroughs were tearing up the airwaves and the internets. From all the thrilling neurological adventures we covered over the past year, we’ve collected five stories we want to make absolutely sure you didn’t miss.
A Roadmap of Brain Wiring
Neuroscientists like to compare the task of unraveling the brain’s connections to the frustration of untangling the cords beneath your computer desk – except that in the brain, there are hundreds of millions of cords, and at least one hundred trillion plugs. Even with our most advanced computers, some researchers were despairing of ever seeing a complete connectivity map of the human brain in our lifetimes. But thanks to a team led by Van Wedeen at the Martinos Center for Biomedical Imaging at Massachusetts General Hospital, 2012 gave us an unexpectedly clear glimpse of our brains’ large-scale wiring patterns. As it turns out, the overall pattern isn’t so much a tangle as a fabric – an intricate, multi-layered grid of cross-hatched neural highways. What’s more, it looks like our brains share this grid pattern with many other species. We’re still a long way from decoding how most of this wiring functions, but this is a big step in the right direction.
Scientists have been stimulating rats’ pleasure centers since the 1950s – but 2012 saw the widespread adoption of a new brain-stimulation method that makes all those wires and incisions look positively crude. Researchers in the blossoming field of optogenetics develop delicate devices that control the firing of targeted groups of neurons – using only light itself. By hooking rats up to a tiny fiber-optic cable and firing lasers directly into their brains, a team led by Garret D. Stuber at the University of North Carolina at Chapel Hill School of Medicine were able to isolate specific neurochemical shifts that cause rats to feel pleasure or anxiety – and switch between them at will. This method isn’t only more precise than electrical stimulation – it’s also much less damaging to the animals.
Programmable Brain Cells
Pluripotent stem cell research took off like a rocket in 2012. After discovering that skin cells can be genetically reprogrammed into stem cells, which can in turn be reprogrammed into just about any cell in the human body, a team led by Sheng Ding at UCSF managed to engineer a working network of newborn neurons from a harvest of old skin cells. In other words, the team didn’t just convert skin cells into stem cells, then into neurons – they actually kept the batch of neurons alive and functional long enough to self-organize into a primitive neural network. In the near future, it’s likely that we’ll be treating many kinds of brain injuries by growing brand-new neurons from other kinds of cells in a patient’s own body. This is already close on the horizon for liver and heart cells – but the thought of being able to technologically shape the re-growth of a damaged brain is even more exciting.
Memories on Disc
We’ve talked a lot about how easily our brains can modify and rewrite our long-term memories of facts and scenarios. In 2012, though, researchers went Full Mad Scientist with the implications of this knowledge, and blew some mouse minds in the process. One team, led by Mark Mayford of the Scripps Research Institute, took advantage of some recently invented technology that enables scientists to record and store a mouse’s memory of a familiar place on a microchip. Mayford’s team figured out how to turn specific mouse memories on and off with the flick of a switch – but they were just getting warmed up. The researchers then proceeded to record a memory in one mouse’s brain, transfer it into another mouse’s nervous system, and activate it in conjunction with one of the second mouse’s own memories. The result was a bizarre “hybrid memory” – familiarity with a place the mouse had never visited. Well, not in the flesh, anyway.
Videos of Thoughts
Our most exciting neuroscience discovery of 2012 is also one of the most controversial. A team of researchers from the Gallant lab at UC Berkeley discovered a way to reconstruct videos of entire scenes from neural activity in a person’s visual cortex. Those on the cautionary side emphasize that activity in the visual cortex is fairly easy to decode (relatively speaking, of course) and that we’re still a long, long way from decoding videos of imaginary voyages or emotional palettes. In fact, from one perspective, this isn’t much different from converting one file format into another. On the other hand, though, these videos offer the first hints of the technological reality our children may inhabit: A world where the boundaries between the objective external world and our individual subjective experiences are gradually blurred and broken down. When it comes to transforming our relationship with our own consciousness – and those of the people around us – it doesn’t get much more profound than that.